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Transcriber's note: A few typographical errors have been corrected: they
are listed at the end of the text. The errata on pp. 70, 118, 162, 310,
352, 367 & 407 have been applied to the text.

       *       *       *       *       *


_PHILOSOPHICAL_

TRANSACTIONS:

GIVING SOME

ACCOMPT

OF THE PRESENT

Undertakings, Studies, and Labours

OF THE

INGENIOUS

IN MANY

CONSIDERABLE PARTS

OF THE

WORLD

_Vol I._

For _Anno_ 1665, and 1666.

In the _SAVOY_,
Printed by _T. N._ for _John Martyn_ at the Bell, a little without
_Temple-Bar_, and _James Allestry_ in _Duck-Lane_,
Printers to the _Royal Society_.

       *       *       *       *       *


TO THE

Royal Society.

_It will not become me, to adde any Attributes to a Title, which has a
Fulness of Lustre from his _Majesties_ Denomination._

_In these Rude Collections, which are onely the Gleanings of my _private_
diversions in broken hours, it may appear, that many Minds and Hands are in
many places industriously employed, under Your Countenance, and by Your
Example, in the pursuit of those Excellent Ends, which belong to Your
Heroical Undertakings._

_Some of these are but the Intimations of large Compilements. And some
Eminent Members of Your _Society_, have obliged the Learned World with
Incomparable _Volumes_, which are not herein mention'd, because they were
finisht, and in great Reputation abroad, before I entred upon this Taske.
And no small Number are at present engaged for those weighty Productions,
which require _both_ Time and Assistance, for their due Maturity. So that
no man can from these Glimpses of Light take any just Measure of Your
Performances, or of Your Prosecutions; but every man may perhaps receive
some benefit from these Parcels, which I guessed to be somewhat conformable
to Your Design._

_This is my Solicitude, That, as I ought not to be unfaithful to those
Counsels you have committed to my Trust, so also that I may not altogether
waste any minutes of the leasure you afford me. And thus have I made the
best use of some of them, that I could devise; To spread abroad
Encouragements, Inquiries, Directions, and Patterns, that may animate, and
draw on_ Universal Assistances.

_The _Great God_ prosper You in the Noble Engagement of Dispersing the true
Lustre of his Glorious Works, and the Happy Inventions of obliging Men all
over the World, to the General Benefit of Mankind: So wishes with real
Affections,_

Your humble and obedient Servant

_HENRY OLDENBURG._

{1}

       *       *       *       *       *




_Numb._ 1.

PHILOSOPHICAL
_TRANSACTIONS._

       *       *       *       *       *

_Munday_, _March_ 6. 1664/5.

       *       *       *       *       *

The Contents.

    _An Introduction to this Tract. An Accompt of the Improvement of
    _Optick Glasses_ at _Rome_. Of the Observation made in _England_, of a
    Spot in one of the Belts of the Planet _Jupiter_. Of the motion of the
    late _Comet_ prædicted. The Heads of many New Observations and
    Experiments, in order to an Experimental _History of Cold_; together
    with some _Thermometrical_ Discourses and Experiments. A Relation of a
    very odd Monstrous _Calf_. Of a peculiar _Lead-Ore_ in _Germany_, very
    useful for Essays. Of an _Hungarian Bolus_, of the same effect with the
    _Bolus Armenus_. Of the New _American_ Whale-fishing about the
    _Bermudas_. A Narative concerning the success of the _Pendulum-watches_
    at Sea for the _Longitudes_; and the Grant of a _Patent_ thereupon. A
    Catalogue of the Philosophical Books publisht by _Monsieur de Fermat_,
    Counsellour at _Tholouse_, lately dead._

       *       *       *       *       *

_The Introduction._

Whereas there is nothing more necessary for promoting the improvement of
Philosophical Matters, than the communicating to such, as apply their
Studies and Endeavours that way, such things as are discovered or put in
practise by others, it is therefore thought fit to employ the _Press_, as
the most proper way to gratifie those, whose engagement in such Studies,
and delight in the advancement of Learning and profitable Discoveries, doth
entitle them to the knowledge of what this Kingdom, or other parts of the
World, do, from time to time, afford, as well {2} of the progress of the
Studies, Labours, and attempts of the Curious and learned in things of this
kind, as of their compleat Discoveries and performances: To the end, that
such Productions being clearly and truly communicated, desires after solid
and usefull knowledge may be further entertained, ingenious Endeavours and
Undertakings cherished, and those, addicted to and conversant in such
matters, may be invited and encouraged to search, try, and find out new
things, impart their knowledge to one another, and contribute what they can
to the Grand design of improving Natural knowledge, and perfecting all
_Philosophical Arts_, and _Sciences_. All for the Glory of God, the Honour
and Advantage of these Kingdoms, and the Universal Good of Mankind.

       *       *       *       *       *

_An Accompt of the improvement of_ Optick Glasses.

There came lately from _Paris_ a Relation, concerning the Improvement of
_Optick Glasses_, not long since attempted at _Rome_ by Signor _Giuseppe
Campani_, and by him discoursed of, in a Book, Entituled, _Ragguaglio di
nuoue Osservationi_, lately printed in the said City, but not yet
transmitted into these parts; wherein these following particulars,
according to the Intelligence, which was sent hither, are contained.

The _First_ regardeth the excellency of the long _Telescopes_, made by the
said _Campani_, who pretends to have found a way to work great _Optick
Glasses_ with a Turne-tool, without any Mould: And whereas hitherto it hath
been found by Experience, that _small_ Glasses are in proportion better to
see with, upon the Earth, than the _great_ ones; that Author affirms, that
his are equally good for the Earth, and for making Observations in the
Heavens. Besides, he useth three Eye-Glasses for his great _Telescopes_,
without finding any _Iris_, or such Rain-bow colours, as do usually appear
in ordinary Glasses, and prove an impediment to Observations.

The _Second_, concerns the _Circle of Saturn_, in which he hath observed
nothing, but what confirms Monsieur _Christian Huygens de Zulichem_ his
Systeme of that Planet, published by that worthy Gentleman in the year,
1659. {3}

The _Third_, respects _Jupiter_, wherein _Campani_ affirms he hath observed
by the goodness of his Glasses, certain _protuberancies_ and
_inequalities_, much greater than those that have been seen therein
hitherto. He addeth, that he is now observing, whether those sallies in the
said _Planet_ do not change their scituation, which if they should be found
to do, he judgeth, that _Jupiter_ might then be said to turn upon his
_Axe_; which, in his opinion, would serve much to confirm the opinion of
_Copernicus_. Besides this, he affirms, he hath remarked in the _Belts_ of
_Jupiter_, the shaddows of his _satellites_, and followed them, and at
length seen them emerge out of his Disk.

       *       *       *       *       *

_A Spot in one of the Belts of Jupiter._

The Ingenious Mr. _Hook_ did, some moneths since, intimate to a friend of
his, that he had, with an excellent twelve foot Telescope, observed, some
days before, he than spoke of it, (_videl._ on the ninth of _May_, 1664,
about 9 of the clock at night) a small Spot in the biggest of the 3
obscurer _Belts_ of _Jupiter_, and that, observing it from time to time, he
found, that within 2 hours after, the said Spot had moved from East to
West, about half the length of the Diameter of _Jupiter_.

       *       *       *       *       *

_The Motion of the late Comet prædicted._

There was lately sent to one of the _Secretaries_ of the _Royal Society_ a
Packet, containing some Copies of a Printed Paper, Entituled, The
_Ephemerides_ of the _Comet_, made by the same Person, that sent it, called
_Monsieur Auzout_, a _French_ Gentleman of no ordinary Merit and Learning,
who desired, that a couple of them might be recommended to the said
_Society_, and one to their _President_, and another to his Highness Prince
_Rupert_, and the rest to some other Persons, nominated by him in a Letter
that accompanied this present, and known abroad for their singular
abilities and knowledge in Philosophical Matters. The end of the
Communication of this Paper was, That, the motion of the _Comet_, that hath
lately appeared, having been prædicted by the said _Monsieur {4} Auzout_,
after he had seen it (as himself affirms) but 4 or 5 times: the _Virtuosi_
of _England_, among others, might compare also their Observations with his
_Ephemerides_, either to confirm the _Hypothesis_, upon which the _Author_
had before hand calculated the way of this Star, or to undeceive him, if he
be in a mistake. The said Author Dedicateth these his conceptions to the
most Christian King, telling him, that he presents Him with a design, which
never yet was undertaken by any _Astronomer_, all the World having been
hitherto perswaded, that the motions of _Comets_ were so irregular, that
they could not be reduced to any Laws, and men having contented themselves,
to observe exactly the places, through which they did pass; but no man,
that he knows, having been so bold as to venture to foretel the places,
through which they should pass, and where they should cease to appear:
Whereas he exhibites here the _Ephemerides_, determining day by day, in
what place of the Heavens this _Comet_ shall be, at what hour it shall be
in its _Meridian_, and at what hour it shall set; untill its too great
remoteness, or the approach of the Sun, hide it from our eyes. Descending
to particulars, he saith, that this Star, being disengaged from the beams
of the Sun might have been observed, if his conjectures be good, ever since
it hath been of 17 or 18 degrees _Southern Latitude_, and that about the
middle of _November_ last, and sooner, unless it have been too small: That
however it hath been seen in _Holland_ ever since the _2d._ of _December_
last, at which time, according to his reckoning, the Diurnal motion of the
_Comet_ should already amount to 17 or 18 minutes. He finds, that this Star
moveth _just enough_ in the Plan of a _Great Circle_, which inclineth to
the _Equinoctial_ about 30 degrees, and to the _Ecliptick_ about 49d. or
49½ cutting the _Equator_ at about 45_d_½, and the _Ecliptick_ at the 28_d_
of _Aries_, or a little more. He saith _just enough_, because he thinks,
there may perhaps be some _parallaxe_, which he wisheth could be
determined.

Hence, (_so he goes on_) every one who pleaseth, may see, in tracing the
_Comet_ upon the _Globe_, through, or by which Stars it hath passed and
shall pass; adding, that there will be neither cause to wonder, that having
descended to about 6. deg. beneath the _Tropick_ of _Capricorn_, he hath
remounted afterwards, and shall go {5} on ascending so, as to pass the
_Æquinoctial_, and perhaps proceed to 15. degrees _Northern Declination_,
if it do not disappear before that time, by reason of its remoteness: Nor
to believe, that there have been two _Comets_, upon its being seen again
the 31. of _December_; since, according to him, it ought to have been so,
if it continue to move in a _Great Circle_.

Having hereupon shewed, how the motion is to be traced upon the _Globe_, he
finds, that, according to his Calculation, this _Comet_ was to pass the
_Tropick_ of _Capricorn_ about the 16 of _December_, and being entred into
the Sign of _Virgo_ on the 20. of the same month, and having been in
_Quadrat_ with the _Sun_, it should still descend, until the 26 of
_December_ in the morning, and then enter into _Leo_; that having entred,
the 28. of the same month, into _Cancer_, and been, a little after that
time, in its greatest Inclination to the _Ecliptick_, vid in the 28. degree
of _Leo_, it was to repass the _Southern Tropick_, over against the _little
Dogg_, on the 29. of _December_ about 9 or 10 of the clock in the morning,
after it had been opposite to the _Sun_ 2. or 3. hours before; and that on
the 29. of _December_ in the evening it should be in _Gemini_; and at the
very beginning of the New year, enter into _Taurus_.

After this, our Author finds, that this _Comet_, according to his account,
should pass the _Æquator_, on the 4. of _January_ before noon, and that
about 5. or 6. of the clock in the evening of that day it was to come into
the jaw of the _Whale_, and the 9. of the same, at 6. of the clock it
should come close to the small Star of the _Whale_, which is in its way, a
little below. At length he finds that it was to enter into _Aries_ on the
12. of _January_, and to cut the _Ecliptick_ on the 16. of the same month
about noon, at which time it was to be again in _Quadrat_ with the _Sun_,
whence drawing a little to above the _Northern Line_ of _Pisces_, it should
in his opinion cease to appear a little beyond that place, without going as
far as to the middle of _Aries_, if so be that its remoteness make it not
disappear sooner.

He continueth, and saith, that this _Comet_ shall not arrive to the place
over against the _Line_ of _Pisces_ till the 10 of _February_, & that then
its _Diurnal_ motion shall not exceed 8 minutes, and not 5 minutes about
the 20 of the same month: and that in the {6} beginning of _March_, if we
see it so long, the said motion shall not exceed 4 minutes, and so shall be
still diminishing; except the _Comet_ become _Retrograde_, which, as very
important, he would have well observed; as also, whether its motion will be
about the end more or less swift, than he hath calculated it.

He subjoyneth, that the greatest way, which this Star could make in 24.
hours, hath been 13. d. 25'; and in one houre, about 34'; and thinking it
probable, that about the time, when it made so much way, it should be
nearest to the _Earth_, he concludeth that its motion in 24. hours must be,
in its least distance from the _Earth_, as about 3. to 14, or 1. to 4-2/3,
and that its motion in one hour was to be to the same least distance, as
about 1. to 102-1/7.

But that, which he judgeth most remarkable, is, that he found by his
Calculation, that the said least distance should be on the 29. of
_December_, when the _Comet_ was opposite to the Sun; which he does not
know whether it may not serve to decide the grand Question concerning the
_Motion of the Earth_.

He taketh further notice, that the _Tayl_ of the _Comet_ was to turn
_Westward_, with a point to the _North_, until the 29. of _December_, at
which time it was to be opposite to the _Sun_, and that then the said
_Tayl_ was to look directly _North_; but that, after that time, the _Tayl_
was to turn _Eastward_, and continue to do so, until it disappear; and that
it shall draw a little towards the _North_, until the 8. or 10. of
_February_, at which time the _Tayl_ is to be parallel to the _Æquator_, as
if the _Comet_ be _yet_ seen for some time after, the _Tayl_ shall go a
little lower towards the _South_, but grow smaller.

He finds by his _Hypothesis_, that on the 2. of _December_, which is the
first observation, that he hath heard of, this Star was to be about 7.
times more remote from the _Earth_, than when it was in its _Perigeum_; and
that it will be again in an equall remoteness from the _Earth_, on the 27.
of _January_, so that he is of opinion, that in case this _Comet_ have not
been seen before the 2. of _December_, it will not be seen any more after
the 27. of _January_.

He wishes above all things, that it might be very exactly observed, at what
Angle the way of the _Comet_ cuts the _Æquator_, and, most of all, the
_Ecliptick_, that so it may be seen, whether {7} there hath not been some
_Parallaxe_ in the _Circle_ of his Motion; as also, that some observations
could be had of its greatest descent beneath the _Tropick of Capricorn_ in
the more _Southern_ parts, where he saith it would have been without
_Refractions_; Moreover of the Time, when it hath been in _Quadrat_ with
the _Sun_ about the 20 of _December_; and that also very exact Observation
might be made of the time of its being again in _Quadrat_ with the _Sun_,
which, according to him, was to be _January_ 16.

He wishes also, that some in _Madagascar_ may have observed this Star;
Seeing that it began to appear over the middle of that _Island_, and passed
twice over their heads; he judgeth, that they have seen it before us. And
he wisheth lastly, that there were some intelligent person in _Guiana_ to
observe it there, seeing that within a few daies, according to his
reckoning, it will pass over their Heads, and will not remove from thence
but 8 or 10 degrees Northward, where he saith, it will disappear; thinking
it improbable, that it can still appear, after the _Sun_ shall have passed
it.

This Account beareth date of the 2. _January_, new stile, 1665. and the
Author thereof addeth this Note, That, seeing it could not be printed nor
distributed so soon as he desired, he hath had the opportunity to verifie
it by some Observations, from which he affirms he hath found no sensible
difference; or, if there be, that it proceeds only from thence, that the
Stars have advanced, since his _Globe_ was made. He concludeth, that if
this continue, and the first Observations do likewise agree, or that the
differences do arrive within the Times ghessed by him, that he hopes, he
shall determine both the _Distance_ and the _Magnitude_ of this _Comet_;
and that perhaps one may be enabled to decide the Question of the _Motion
of the Earth_. In the interim, he assureth, that he hath not changed the
least number in his Calculations, and that _Monsieur Huygens_, and several
French Gentlemen, to whom he saith, he hath given them long since, can bear
him witness that he hath done so; as also many other friends of his, who
saw upon his _Globe_, several daies before, the way of the _Comet_ from day
to day.

Thus for the _Parisian_ Account of the Comet, which is here inserted at
large, that the intelligent and curious in _England_ may {8} compare their
Observations therewith, either to verifie these _Prædictions_, or to shew
wherein they differ; which is (as was also hinted above) the design of this
_Philosophical Prophet_ in dispersing his Conceptions, who declareth
himself ready, in case he be mistaken in his reckoning, to learn another
_Hypothesis_, to explicate these admirable appearances by.

       *       *       *       *       *

_An Experimental History of Cold._

There is in the Press, a New _Treatise_, entituled, _New Observations and
Experiments in order to an Experimental History of Cold_, begun by that
Noble Philosopher, Mr. _Robert Boyle_, and in great part already Printed;
He did lately very obligingly present several Copies of so much as was
Printed, to the _Royal Society_, with a desire that some of the Members
thereof might be engaged to peruse the Book, and select out of it for
trial, the hints of such Experiments, as the _Author_ there wisheth might
be either yet made or prosecuted. The Heads thereof are,

1. Experiments touching Bodies capable of Freezing others.

2. Experiments and Observations touching Bodies Disposed to be Frozen.

3. Experiments touching Bodies, Indisposed to be Frozen.

4. Experiments and Observations touching the Degrees of Cold in several
Bodies.

5. Experiments touching the Tendency of Cold Upwards or Downwards.

6. Experiments and Observations touching the Preservation and Destruction
of (Eggs, Apples, and other) Bodies by Cold.

7. Experiments touching the Expansion of Water and Aqueous Liquors by
Freezing.

8. Experiments touching the Contraction of Liquors by Cold.

9. Experiments in Consort, touching the Bubbles, from which the Levity of
Ice is supposed to proceed.

10. Experiments about the Measure of the Expansion and the Contraction of
Liquors by Cold.

11. Experiments touching the Expansive Force of Freezing Water.

12. Experiments touching a New way of estimating the {9} Expansive force of
Congelation, and of highly compressing Air without Engines.

13. Experiments and Observations touching the Sphere of Activity of Cold.

14. Experiments touching differing _Mediums_, through which Cold may be
diffused.

15. Experiments and Observations touching Ice.

16. Experiments and Observations touching the duration of Ice and Snow, and
the destroying of them by the Air, and several Liquors.

17. Considerations and Experiments touching the _Primum Frigidum_.

18. Experiments and Observations touching the Coldness and Temperature of
the Air.

19. Of the strange Effects of Cold.

20. Experiments touching the weight of Bodies frozen and unfrozen.

21. Promiscuous Experiments and Observations concerning Cold.

This Treatise will be dispatched within a very short time, and would have
been so, ere this, if the extremity of the late Frost had not stopt the
Press. It will be accompanied with some Discourses of the same _Author_,
concerning _New Thermometrical Experiments and Thoughts_, as also, with an
Exercitation about the _Doctrine of the Antiperistasis_: In the former
whereof is _first_ proposed this _Paradox_, That not only our Senses, but
common Weather-glasses, may mis-inform us about Cold. _Next_, there are
contained in this part, New Observations about the deficiencies of
Weather-glasses, together with some considerations touching the New or
_Hermetrical_ Thermometers. _Lastly_, they deliver another _Paradox_,
touching the cause of the Condensation of the Air, and Ascent of water by
cold in common Weather-glasses. The latter piece of this part contains an
Examen of _Antiperistasis_, as it is wont to be _taught_ and _proved;_ Of
all which there will, perhaps, a fuller account be given by the Next. {10}

       *       *       *       *       *

_An Account of a very odd Monstrous Calf._

By the same Noble person was lately communicated to the _Royal Society_ an
account of a very Odd Monstrous Birth, produced at _Limmington_ in
_Hampshire_, where a Butcher, having caused a Cow (which cast her Calf the
year before) to be covered, that she might the sooner be fatted, killed her
when fat, and opening the Womb, which he found heavy to admiration, saw in
it a Calf, which had begun to have hair, whose hinder Leggs had no Joynts,
and whose Tongue was, _Cerberus_-like, triple, to each side of his Mouth
one, and one in the midst: Between the Fore-leggs and the Hinder-leggs was
a great Stone, on which the Calf rid: the _Sternum_, or that part of the
Breast, where the Ribs lye, was also perfect Stone; and the Stone, on which
it rid, weighed twenty pounds and a half; the outside of the Stone was of
Grenish colour, but some small parts being broken off, it appeared a
perfect Free-stone. The Stone, according to the Letter of Mr. _David
Thomas_, who sent this Account to Mr. _Boyle_, is with Doctor _Haughteyn_
of _Salisbury_, to whom he also referreth for further Information.

       *       *       *       *       *

_Of a peculiar Lead-Ore of _Germany_, and the Use thereof._

There was, not long since, sent hither out of _Germany_ from an inquisitive
Physician, a List of several _Minerals_ and _Earths_ of that Country, and
of _Hungary_, together with a _Specimen_ of each of them: among which there
was a kind of _Lead-Ore_ which is more considerable than all the rest,
because of its singular use for _Essays_ upon the _Coppell_, seeing that
there is not any other _Mettal_ mixed with it. 'Tis found in the _Upper
Palatinate_, at a place called _Freyung_, and there are two sorts of it,
whereof one is a kind of Crystalline Stone, and almost all good Lead; the
other not so rich, and more farinaceous. By the information, coming along
with it, they are fetcht, not from under the ground, but, the Mines of that
place having lain long neglected, by reason of the Wars of _Germany_ and
the increase of Waters, the people, living {11} there-about take it from
what these Forefathers had thrown away, and had lain long in the open Air.
The use above mentioned being considerable, the person, who sent it, hath
been intreated, to inform what quantities may be had of it, if there should
be occasion to send for some.

       *       *       *       *       *

_Of an Hungarian Bolus, of the same Effect with the Bolus Armenus._

The same person gave notice also, that, besides the _Bolus Armenus_, and
the _Terra Silesiaca_, there is an Earth to be found in _Hungary_ about the
River _Tockay_, thence called _Bolus Tockaviensis_, having as good effects
in _Physick_, as either of the former two, and commended by experience in
those parts, as much as it is by _Sennertus_ out of _Crato_, for its
goodness.

       *       *       *       *       *

_Of the New _American_ Whale-fishing about the Bermudas._

Here follows a Relation, somewhat more divertising, than the precedent
Accounts, which is about the new _Whale fishing_ in the _West-Indies_ about
the _Bermudas_, as it was delivered by an understanding and hardy Sea-man,
who affirmed he had been at the killing work himself. His account, as far
as remembred, was this; that though hitherto all Attempts of mastering the
Whales of those Seas had been unsuccesful, by reason of the extraordinary
fierceness and swiftness of these monstrous Animals; yet the enterprise
being lately renewed, and such persons chosen and sent thither for the
work, as were resolved not to be baffled by a Sea-monster, they did prosper
so far in this undertaking, that, having been out at Sea, near the said
Isle of _Bermudas_, seventeen times, and fastned their Weapons a dozen
times, they killed in these expeditions 2 old Female-Whales, and 3 Cubs,
whereof one of the old ones, from the head to the extremity of the Tayl,
was 88. Foot in length, by measure; its Tayl being 23. Foot broad, the
swimming Finn 26. Foot long, and the Gills three Foot long: having great
bends underneath from the Nose to the Navil; upon her after-part, a Finn on
the back; being within {12} paved (this was the plain Sea-man's phrase)
with fat, like the Cawl of a Hog.

The other old one, he said, was some 60. Foot long. Of the Cubs, one was
33. the other two, much about 25 or 26. Foot long.

The shape of the Fish, he said, was very sharp behind, like the ridge of a
house; the head pretty bluff, and full of bumps on both sides; the back
perfectly black, and the belly white.

Their celerity and force he affirmed to be wonderful, insomuch that one of
those Creatures, which he struck himself, towed the boat wherein he was,
after him, for the space of six or seven Leagues, in ¾ of an hours time.
Being wounded, he saith, they make a hideous roaring, at which, all of that
kind that are within hearing, come towards that place, where the Animal is,
yet without striking, or doing any harm to the wary.

He added, that they struck one of a prodigious bigness, and by guess of
above 100 foot long. He is of opinion, that this Fish comes nearest to that
sort of Whales, which they call the _Jubartes_; they are without teeth, and
longer than the _Greenland_-Whales, but not so thick.

He said further, that they fed much upon Grass, growing at the bottom of
the Sea; which, he affirmed, was seen by cutting up the great Bag of Maw,
wherein he had found in one of them about two or three Hogsheads of a
greenish grassy matter.

As to the quantity and nature of the Oyl which they yield, he thought, that
the largest sort of these Whales might afford seven or eight Tuns if well
husbanded, although they had lost much this first time, for want of a good
Cooper; having brought home but eleven Tuns. The Cubbs, by his relation, do
yield but little, and that is but a kind of a Jelly. That which the old
ones render, doth candy like Porks Grease, yet burneth very well. He
observed, that the Oyl of the Blubber is as clear and fair as any Whey: but
that which is boyled out of the Lean, interlarded, becomes as hard as
Tallow, spattering in the burning and that which is made of the Cawl,
resembleth Hoggs grease.

One, but scarce credible, quality of this Oyl, he affirms to be, that
though it be boiling, yet one may run ones hand into it without scalding;
to which he adds, that it hath a very healing {13} Vertue for cuttings,
lameness, &c., the part affected being anointed therewith. One thing more
he related, not to be omitted, which is, that having told, that the time of
catching these Fishes was from the beginning of _March_, to the end of
_May_, after which time they appeared no more in that part of the Sea: he
did, when asked, whither they then retired, give this Answer, That it was
thought, they went into the Weed-beds of the Gulf of _Florida_, it having
been observed, that upon their Fins and Tails they have store of Clams or
Barnacles, upon which, he said, Rock-weed or Sea-tangle did grow a hand
long; many of them having been taken of them, of the bigness of great
Oyster-shels, and hung upon the Governour of _Bermudas_ his Pales.

       *       *       *       *       *

_A Narrative concerning the success of Pendulum-Watches at Sea for the
Longitudes._

The Relation lately made by Major _Holmes_, concerning the success of the
_Pendulum-Watches_ at Sea (two whereof were committed to his Care and
Observation in his last voyage to _Guiny_ by some of our Eminent
_Virtuosi_, and Grand Promoters of Navigation) is as followeth;

The said _Major_ having left that Coast, and being come to the Isle of St.
_Thomas_ under the _Line_ accompanied with four Vessels, having there
adjusted his Watches, put to Sea, and sailed Westward, seven or eight
hundred Leagues, without changing his course; after which, finding the Wind
favourable, he steered towards the Coast of _Africk_, North-North-East. But
having sailed upon that _Line_ a matter of two or three hundred Leagues,
the Masters of the other Ships, under his Conduct, apprehending that they
should want Water, before they could reach that Coast, did propose to him
to steer their Course to the _Barbadoes_, to supply themselves with Water
there. Whereupon the said Major, having called the Master and Pilots
together, and caused them to produce their Journals and Calculations, it
was found, that those Pilots did differ in their reckonings from that of
the Major, one of them eighty Leagues, another about an hundred, and the
third, more; but the Major judging by his _Pendulum-Watches_, that they
were only some thirty Leagues distant from {14} the Isle of _Fuego_, which
is one of the Isles of _Cape Verde_, and that they might reach it next day,
and having a great confidence in the said Watches, resolved to steer their
Course thither, and having given order so to do, they got the very next day
about Noon a sight of the said Isle of _Fuego_, finding themselves to sail
directly upon it, and so arrived at it that Afternoon, as he had said.
These Watches having been first Invented by the Excellent Monsieur
_Christian Hugens_ of _Zulichem_, and fitted to go at Sea, by the Right
Honourable, the Earl of _Kincardin_, both Fellows of the _Royal Society_,
are now brought by a New addition to a wonderful perfection. The said
Monsieur _Hugens_, having been informed of the success of the Experiment,
made by _Major Holmes_, wrought to a friend at _Paris_ a Letter to this
effect;

Major _Holmes_ at his return, hath made a relation concerning the
usefulness of _Pendulums_, which surpasseth my expectation: I did not
imagine that the Watches of this first Structure would succeed so well, and
I had reserved my main hopes for the New ones. But seeing that those have
already served so succesfully, and that the other are yet more just and
exact, I have the more reason to believe, that the Invention of
_Longitudes_ will come to its perfection. In the mean time I shall tell
you, that the _States_ did receive my Proposition, when I desired of them a
Patent for these new Watches, and the recompense set a-part for the
invention in case of success; and that without any difficulty they have
granted my request, commanding me to bring one of these Watches into their
Assembly, to explicate unto them the Invention, and the application thereof
to the _Longitudes_; which I have done to their contentment. I have this
week published, that the said Watches shall be exposed to sale, together
with an Information necessary to use them at Sea: and thus I have broken
the Ice. The same Objection, that hath been made in your parts against the
exactness of these _Pendulums_, hath also been made here; to wit, that
though they should agree together, they might fail both of them, by reason
that the Air at one time might be thicker, than at another. But I have
answered, that this difference, if there be any, will not be at all
perceived in the _Penduls_, seeing that the continuall Observations, made
in Winter from day to day, until Summer, have shewed me that {15} they have
alwaies agreed with the Sun. As to the Printing of the _Figure_ of my New
Watch, I shall defer that yet a while: but it shall in time appear with all
the Demonstrations thereof, together with a _Treatise_ of _Pendulums_,
written by me some daies since, which is of a very subtile Speculation.

       *       *       *       *       *

_The Character, lately published beyond the Seas, of an Eminent person, not
long since dead at _Tholouse_, where he was a Councellor of Parliament._

It is the deservedly famous _Mounsieur de Fermat_, who was, (saith the
Author of the Letter) one of the most Excellent Men of this Age, a _Genius_
so universal, and of so vast an extent, that if very knowing and learned
Men had not given testimony of his extraordinary merit, what with truth can
be said of him, would hardly be believed. He entertained a constant
correspondence with many of the most Illustrious Mathematicians of
_Europe_, and did excel in all the parts of Mathematical Science: a
Testimony whereof he hath left behind him in the following Books.

A Method for the Quadrature of _Parabola's_ of all degrees.

A Book _De Maximis & Minimis_, which serveth not only for the determination
of Problems of _Plains_ and _Solids_, but also for the invention of
_Tangents_ and _Curve Lines_, and of the _Centres_ of Gravity in Solids;
and likewise for Numerical Questions.

An Introduction to the Doctrine of _Plains_ and _Solids_, which is an
_Analytical_ Treatise, concerning the solution of _Plains_ and _Solids_,
which has been seen (as the Advertiser affirms) before Monsieur _Des
Cartes_ had publish'd any thing upon this Subject.

A Treatise _De Contactibus Sphæricis_, where he hath demonstrated in
_Solids_, what Mr. _Viet_, Master of Requests, had but demonstrated in
_Plains_.

Another Treatise, wherein he establisheth and demonstrateth the two Books
of _Apollonius Pergæus_, of _Plains_.

And a General Method for the dimension of _Curve Lines_, &c. Besides,
having a perfect knowledge in Antiquity, he was consulted from all parts
upon the difficulties that did emerg therein: he hath explained abundance
of obscure places, that are {16} found in the Antients. There have been
lately printed some of his Observations upon _Athenæus_; and he that hath
interpreted _Benedetto Castelli_, of the Measure of running waters, hath
thence inserted in his Work a very handsome one upon an Epistle of
_Synesius_, which was so difficult, that the Jesuit _Petavius_, who hath
commented upon this Author, acknowledges, that he could not understand it.

He hath also made many Observations upon _Theon of Smyrne_, and upon other
Antient Authors: but most part of them are not found but scattered in his
Epistles, because he did not write much upon these kinds of Subjects, but
to satisfie the curiosity of his friends.

All these Mathematical Works, and all these curious searches in Antiquity,
did not hinder this great _Virtuoso_ from discharging the duties of his
place with much assiduity, and with so much ability, that he hath had the
reputation of one of the greatest _Civilians_ of his Age.

But that, which is most of all surprizing to many, is, that with all that
strength of understanding, which was requisite to make good these rare
qualities, lately mentioned, he had so polite and delicate parts, that he
composed _Latin_, _French_, and _Spanish_ Verses with the same elegancy, as
if he had lived in the time of _Augustus_, and passed the greatest part of
his life at the Courts of _France_ and _Spain_.

More particulars will perhaps be mention'd of the Works of this Rare
person, when all things, that he hath publish'd, shall be recovered, and
when liberty shall be obtained of his Worthy Son, to impart unto the World
the rest of his Writings, hitherto unpublished.

       *       *       *       *       *


_LONDON,_

Printed with Licence, By _John Martyn_, and _James Allestry_, Printers to
the _Royal-Society_.

{17}

       *       *       *       *       *




_Num._ 2.

PHILOSOPHICAL
_TRANSACTIONS._

       *       *       *       *       *

_Munday_, _April_ 3. 1665.

       *       *       *       *       *

The Contents.

    _Extract of a Letter written from _Rome_, concerning the late _Comet_,
    and a _New_ one. Extract of another Letter from _Paris_, containing
    some Reflections on the precedent _Roman_ Letter. An Observation
    concerning some particulars, further considerable in the _Monster_,
    that was Mention'd in the first Papers of these _Philosophical
    Transactions_. Extract of a Letter written from _Venice_, concerning
    the Mines of _Mercury_ in Friuly. Some Observations, made in the
    ordering of _Silk-worms_. An Account of Mr. _Hooks Micrographia_, or
    the Physiological descriptions of _Minute Bodies_, made by _Magnifying
    Glasses_._

       *       *       *       *       *

_Extract of a Letter, lately written from _Rome_, touching the late Comet,
and a New one._

I Cannot enough wonder at the strange agreement of the thoughts of that
acute French Gentleman, Monsieur _Auzout_, in the _Hypothesis_ of the
Comets motion, with mine; and particularly, at that of the _Tables_. I have
with the same method, whereby I find the motion of this Comet, easily found
the Principle of that Author's _Ephemerides_, which he then thought not fit
to declare; and 'tis this, that this Comet moves about the _Great Dog_, in
so great a Circle, that that portion, which is {18} described, is exceeding
small in respect of the whole circumference thereof, and hardly
distinguishable by us from a streight line.

Concerning the New Comet you mention, I saw it on the 11. of _February_,
about the 24. deg. of _Aries_, with a Northern latitude of 24. deg. 40.
min. The cloudy weather hath not yet permitted me to see it in _Andromeda_,
as others affirm to have done.

       *       *       *       *       *

_Extract of a Letter, written from _Paris_, containing some Reflections on
part of the precedent _Roman_ Letter._

As to the _Hypothesis_ of _Georg. Domenico Cassini_, touching the motion of
the _Comet_ about the _Great Dog_ in a Circle, whose Centre is in a
streight line drawn from the Earth through the said Star, I believe it will
shortly be publish'd in print, as a thought I lighted upon in discoursing
with one of my Friends, who did maintain, that it turned about a Centre,
because that its _Perigee_ had been over against the _Great Dog_, as I had
noted in my _Ephemerides_. This particular I did long since declare to many
of my acquaintance, whereof some or other will certainly do me that right,
as to let the world know it by the Press. I have added an Observation,
which I find not, that Signior _Cassini_ hath made, _viz._ that there was
ground to think, that the _Comet_ of 1652. was the same with the present,
seeing that besides the parity of the swiftness of its motion, the
_Perigee_ thereof was also over against the _Great Dog_, if the
Observations extant thereof, deceive not. But, to make it out, what ground
I had for these thoughts, I said, that if they were true, the Comet must
needs acomplish its revolution from 10. to 12. years, or thereabout. But,
seeing it appears not by History, that a Comet hath been seen at those
determinate distances of time, nor that over against the _Perigee_ of all
the other Comets, whereof particular observations are recorded, are alwaies
found Stars of the first Magnitude, or such others, as are very notable,
besides other reasons, that might be alledged, I shall not pursue this
speculation; but rather {19} suggest what I have taken notice of in my
reflexions upon former Comets, which is, that more of them enter inter our
Systeme by the sign of _Libra_ and about _Spica virginis_, than by all the
other parts of the Heavens. For, both the present Comet, and many others
registred in History, have entred that way, and consequently passed out of
it by the sign _Aries_, by which also many have entred.

I did found my _Hypothesis_ upon three Observations only, _viz._ those of
the 22, 26, and 31. of _December_. Nor have I done, as some have fancied of
me, who having been able to observe the Comet, the 27, 28, 29, 30, and 31.
of _December_, and to see the diminution of its motion, have judged, that I
had only determined that diminution for the time to come, conform to the
augmentation thereof in time passed until the 29. of _December_. For
_January_ 1. (on which day I composed my _Ephemerides_) I knew not (nor any
person here) that the motion of the Comet did diminish; but on the
contrary, most men believed, it was not the same Comet. But Signior
_Cassini_ knows very well, that that was not necessary, seeing that two
portions of a _Tangent_ being given, and the _Angles_ answering thereunto,
'tis easie to find the position and magnitude of its Circle. The reason,
which I think the true one, of the diminution of its Motion in Longitude,
and of its Retrogradation, by me conjectured in my _Ephemerides_, I began
to be assured of, _Febr._ 10. For until the sixth, the Comet had alwaies
advanced, as Signior _Cassini_ also hath very well noted: but after that
day, I found that it returned in augmenting alwaies its Latitude. And I
have constantly observed it, until _March_ 8. between many Stars, which
must be the same with these mentioned by _Cassini_, whereof the number was
so great, that I think, I saw of them _March_ 6. with one _Aperture_ of my
Glass, more than 40. or 50. and especially, above the head of _Aries_; but
I did not particularly note the scituation of more than 12. or 15; amongst
which I have observed the position of the Comet since _January_ 28. every
day, when the weather did permit, _viz._ _January_ 29. _February_ 3, 6, 10,
17, 19, 24, 26, 27. and _March_ 6, {20} 7, 8. I left it on _March_ 8. at
the 18. of the Horn of _Aries_, almost in the same latitude: and I am apt
to believe, it will be Eclipsed, which I wish I may be able to observe this
evening, if it be not already passed.

If Signior _Cassini_ hath observed it on those daies that I have, he will
be glad to find the conformity of our Observations. I shall only add, that
on _February_ 3. we were surprized, to see the Comet again much brighter
than ordinary, and with a considerable Train. Some did believe, that it
approach'd again to us. But having beheld it with a _Telescope_, I soon
said, that it was joyned with two small Stars, whereof one was pretty
bright, which I had already seen, on _February_ 28. and 29. And this
conjunction gave the _Comet_ that brightness, as it happens to most of the
Stars of the fifth and sixth magnitude, where 2. or 3. or more are
conjoyned, which perhaps would shew but faintly single, though by reason of
their proximity to one another, they appear but one Star. Hence it was,
that I assured my friends here, that the following daies we should no more
see it so bright, because I knew, that there were none such small bright
Stars in the way, which by my former observations I conjectured it was to
move.

       *       *       *       *       *

_An Observation imparted to the Noble Mr. _Boyle_, by Mr. _David Thomas_,
touching some particulars further considerable in the Monster mentioned in
the first Papers of these _Philosophical Transactions_._

Upon the strictest inquiry, I find by one, that saw the Monstrous Calf and
stone, within four hours after it was cut out of the Cows belly, that the
Breast of the Calf was not stony (as I wrote) but that the skin of the
Breast and between the Legs and of the Neck (which parts lay on the smaller
end of the stone) was very much thicker, than on any other part, and that
the Feet of the Calf were so parted as to be like the Claws of a Dog. The
stone I have since seen; it is bigger at one end {21} than the other; of no
plain _Superficies_, but full of little cavities. The stone, when broken,
is full of small peble stones of an Ovall figure: its colour is gray like
free-stone, but intermixt with veins of yellow and black. A part of it I
have begg'd of Dr. _Haughten_ for you, which I have sent to _Oxford_,
whither a more exact account will be conveyed by the same person.

       *       *       *       *       *

_Extract of a Letter, lately written from _Venice_ by the Learned Doctor
_Walter Pope_, to the Reverend Dean of _Rippon_, Doctor _John Wilkins_,
concerning the Mines of Mercury in _Friuli_; and a way of producing _Wind_
by the fall of _Water_._

The mines of _Mercury_ in _Friuli_, a Territory belonging to the
_Venetians_, are about a days Journey and a half distant from _Goritia_
Northwards, at a place call'd _Idria_, scituated in a Valley of the _Julian
Alps_. They have been, as I am inform'd, these 160. years in the possession
of the Emperor, and all the Inhabitants speak the _Sclavonian_ Tongue. In
going thither, we travell'd several hours in the best Wood I ever saw
before or since, being very full of _Firrs_, _Oakes_, and _Beeches_, of an
extraordinary thickness, straitness, and height. The Town is built, as
usually Towns in the _Alps_ are, all of wood, the Church only excepted, and
another House wherein the Overseer liveth. When I was there, in _August_
last, the Valley, and the Mountains too, out of which the _Mercury_ was
dug, were of as pleasant a verdure, as if it had been in the midst of
Spring, which they there attribute to the moistness of the _Mercury_; how
truly, I dispute not. That Mine, which we went into, the best and greatest
of them all, was dedicated to Saint _Barbara_, as the other Mines are to
other Saints, the depth of it was 125. paces, every pace of that Country
being, as they inform'd us, more than 5 of our Feet. There are two ways
down to it; the shortest perpendicular way is that, whereby they bring up
the Mineral in great Buckets, and {22} by which oftentimes some of the
workmen come up and down. The other, which is the usual way, is at the
beginning not difficult, the descent not being much; the greatest trouble
is, that in several places you cannot stand upright: but this holds not
long, before you come to descend in earnest by perpendicular Ladders, where
the weight of on's body is found very sensible. At the end of each Ladder,
there are boards a-cross, where we may breath a little. The Ladders, as we
said, are perpendicular, but being imagined produced, do not make one
Ladder, but several parallel ones. Being at the bottom, we saw no more than
we saw before, only the place, whence the Mineral came. All the way down,
and the bottom, where there are several lanes cut out in the Mountain, is
lined and propt with great pieces of Firr-trees, as thick as they can be
set. They dig the Mineral with Pick-axes, following the veins: 'tis for the
most part hard as a stone, but more weighty; of a Liver-colour, or that of
_Crocus Metallorum_. I hope shortly to shew you some of it. There is also
some soft Earth, in which you plainly see the _Mercury_ in little
particles. Besides this, there are oftentimes found in the Mines round
stones like Flints, of several bignesses, very like those Globes of Hair,
which I have often seen in _England_, taken out of Oxes bellies. There are
also several _Marcasites_ and stones, which seem to have specks of Gold in
them, but upon tryal they say, they find none in them. These round stones
are some of them very ponderous, and well impregnated with _Mercury_;
others light, having little or none in them. The manner of getting the
_Mercury_ is this: They take of the Earth, brought up in Buckets, and put
it into a Sive, whose bottom is made of wires at so great a distance, that
you may put your finger betwixt them: 'tis carried to a stream of running
water, and wash'd as long as any thing will pass through the Sive. That
Earth which passeth not, is laid aside upon another heap: that which
passeth, reserved in the hole, G. in Fig. 1. and taken up again by the
second Man, and so on, to about ten or twelve sives proportionably less. It
often happens in the first hole, where the second Man takes up his {23}
Earth, that there is _Mercury_ at the bottom; but towards the farther end,
where the Intervals of the wires are less, 'tis found in very great
proportion. The Earth laid aside is pounded, and the same operation
repeated. The fine small Earth, that remains after this, and out of which
they can wash no more _Mercury_, is put into Iron retorts and stopt,
because it should not fall into the Receivers, to which they are luted. The
fire forces the _Mercury_ into the Receivers: the Officer unluted several
of them to shew us; I observed in all of them, that he first poured out
perfect _Mercury_, and after that came a black dust, which being wetted
with water discover'd it self to be _Mercury_, as the other was. They take
the _Caput mortuum_ and pound it, and renew the operation as long as they
can get any _Mercury_ out of it.

This is the way of producing the _Mercury_, they call _Ordinary_, which
exceeds that, which is got by washing, in a very great proportion, as you
will perceive by the account annext. All the _Mercury_ got without the use
of Fire, whether by washing, or found in the Mines (for in the digging,
some little particles get together, so that in some places you might take
up two or three spoonfuls of pure _Mercury_) is call'd by them _Virgin
Mercury_, and esteem'd above the rest. I inquir'd of the Officer what
vertue that had more, than the other; he told me that making an _Amalgama_
of Gold and _Virgin Mercury_, and putting it to the fire, that _Mercury_
would carry away all the Gold with it, which common _Mercury_ would not do.

The Engins, employed in these Mines, are admirable; the Wheels, the
greatest that ever I saw in my life; one would think as great as the matter
would bear: all moved by the dead force of the water, brought thither in no
chargeable Aqueduct from a Mountain, 3 Miles distant: the water pumpt from
the bottom of the Mine by 52 pumps, 26 on a side, is contrived to move
other wheels, for several other purposes.

The Labourers work for a _Julio_ a day, which is not above 6 or 7 pence,
and indure not long; for, although none stay {24} underground above 6
hours; all of them in time (some later, some sooner) become _paralitick_,
and dye _hectick_.

We saw there a man, who had not been in the Mines for above half a year
before, so full of _Mercury_, that putting a piece of _Brass_ in his mouth,
or rubbing it in his fingers, it immediately became white like Silver: I
mean he did the same effect, as if he had rubb'd _Mercury_ upon it, and so
paralitick, that he could not with both his hands carry a Glass, half full
of Wine, to his mouth without spilling it, though he loved it too well to
throw it away.

I have been since informed, that here in _Venice_, those that work on the
back-side of Looking-glasses, are also very subject to the _Palsey_. I did
not observe, that they had black Teeth; it may be therefore, that we accuse
_Mercury_ injustly for spoiling the Teeth, when given in _Venereal_
diseases. I confess, I did not think of it upon the place; but, black Teeth
being so very rare in this Country, I think I could not but have markt it,
had all theirs been so.

They use exceeding great quantity of Wood, in making and repairing the
Engins, and in the Furnaces (whereof there are 16. each of them carrying
24. Retorts;) but principally in the Mines, which need continual
reparation, the Fir-trees lasting but a small time under ground. They
convey their Wood thus: About four miles from the Mines, on the sides of
two mountains, they cut down the Trees, and draw them into the interjacent
Valley, higher in the same Valley, so that the Trees, according to the
descent of the water lye betwixt it and _Idria_: with vast charges and
quantities of Wood they made a Lock or Dam, that suffers not any water to
pass; they expect afterwards till there be water enough to float these
Trees to _Idria_; for, if there be not a spring, (as generally there is,)
Rain, or the melting of the Snow, in a short time, afford so much water, as
is ready to run over the Dam, and which (the Flood-gates being open'd)
carries all the Trees impetuously to _Idria_, where the Bridge is built
very strong, and at very oblique Angles to the stream, on purpose to stop
them, and throw them on shore neer the Mines. {25}

Those Mines cost the _Emperour_ heretofore 70000. or 80000. _Florens_
yearly, and yielded less _Mercury_ than at present, although it costs him
but 28000. _Florens_ now. You may see what his Imperial Majesty gets by the
following account, of what _Mercury_ the Mines of _Idria_ have produced
these last three years.


          1661.            l.
  Ordinary _Mercury_     198481
  Virgin _Mercury_         6194
                        --------
                         204675
                        --------

          1662.            l.
  Ordinary _Mercury_     225066
  Virgin _Mercury_         9612
                        --------
                         234678
                        --------

          1663.            l.
  Ordinary _Mercury_     244119
  Virgin _Mercury_        11862
                        --------
                         255981
                        --------

There are alwaies at work 280 persons, according to the relation I received
from a very civil person, who informed me also of all the other particulars
above mentioned, whose name is _Achatio Kappenjagger_; his Office,
_Contra-scrivano per sua Maestà Cesarea in Idria del Mercurio_.

To give some light to this Narrative, take this Diagramme: F. is the water,
C. B. a vessel, into which it runs. DG. EH. FI. are streams perpetually
issuing from that vessel; D. E. F. three sives, the distance of whose wires
at bottom lessen proportionably. G. the place, wherein the Earth, that
pass'd through the sive D. is retained; from whence 'tis taken by the
second man; and what passes through the sive E. is retained in H. and so of
the rest. K. L. M. wast water, which is so much impregnated with _Mercury_,
that it cureth Itches and sordid Ulcers. See Fig. 1.

[Illustration]

I will trespass a little more upon you, in describing the contrivance of
blowing the Fire in the _Brassworks_ of _Tivoli_ neer _Rome_ (it being new
to me) where the Water blows the Fire, not by moving the Bellows, (which is
common) but by affording the Wind. See Fig. II. Where A. is the {26} River,
B. the Fall of it, C. the Tub into which it falls, LG. a Pipe, G. the
orifice of the Pipe, or Nose of the Bellows, GK. the Hearth, E. a hole in
the Pipe, F. a stopper to that hole, D. a place under ground, by which the
water runs away. Stopping the hole E, there is a perpetual strong wind,
issuing forth at G: and G. being stopt, the wind comes out so vehemently at
E, that it will, I believe, make a Ball play, like that at _Frescati_.

[Illustration]

       *       *       *       *       *

_An Extract of a Letter, containing some Observations, made in the ordering
of _Silk-worms_, communicated by that known _Vertuoso_, Mr. _Dudley
Palmer_, from the ingenuous Mr. _Edward Digges_._

I herewith offer to your _Society_ a small parcel of my _Virginian_ Silk.
What I have observed in the ordering of Silk-worms, contrary to the
received opinion, is:

1. That I have kept leaves 24. hours after they are gathered, and flung
water upon them to keep them from withering; yet when (without wiping the
leaves) I fed the worms, I observed, they did as well as those fresh
gathered.

2. I never observed, that the smell of _Tobacco_, or smels that are rank,
did any waies annoy the worm.

3. Our country of _Virginia_ is very much subject to Thunders: and it hath
thundered exceedingly when I have had worms of all sorts, some newly
hatched; some half way in their feeding; others spinning their Silk; yet I
found none of them concern'd in the Thunder, but kept to their business, as
if there had been no such thing.

4. I have made many bottoms of the Brooms (wherein hundreds of worms spun)
of _Holly_; and the prickles were so far from hurting them, that even from
those prickles they first began to make their bottoms.

I did hope with this to have given you assurance, that by retarding the
hatching of seed, two crops of silk or more {27} might be made in a Summer:
but my servants have been remiss in what was ordered, I must crave your
patience till next year.

       *       *       *       *       *

_An account of _Micrographia_, or the _Physiological Descriptions_ of
_Minute Bodies_, made by _Magnifying Glasses_._

The Ingenious and knowing Author of this _Treatise_, Mr. _Robert Hook_,
considering with himself, of what importance a faithful _History of Nature_
is to the establishing of a solid Systeme of _Natural Philosophy_, and what
advantage _Experimental_ and _Mechanical_ knowledge hath over the
Philosophy of _discourse_ and _disputation_, and making it, upon that
account, his constant business to bring into that vast Treasury what
portion he can, hath lately published a Specimen of his abilities in this
kind of study, which certainly is very welcome to the Learned and
Inquisitive world, both for the _New discoveries_ in _Nature_, and the _New
Inventions_ of _Art_.

As to the _former_, the Attentive Reader of this Book will find, that there
being hardly any thing so small, as by the help of _Microscopes_, to escape
our enquiry, a new visible world is discovered by this means, and the Earth
shews quite a new thing to us, so that in every _little particle_ of its
matter, we may now behold almost as great a variety of creatures, as we
were able before to reckon up in the whole _Universe_ it self. Here our
Author maketh it not improbable, but that, by these helps the subtilty of
the composition of Bodies, the structure of their parts, the various
texture of their matter, the instruments and manner of their inward
motions, and all the other appearances of things, may be more fully
discovered; whence may emerge many admirable advantages towards the
enlargement of the _Active_ and _Mechanick_ part of knowledge, because we
may perhaps be enabled to discern the secret {28} workings of _Nature_,
almost in the same manner, as we do those that are the productions of
_Art_, and are managed by _Wheels_, and _Engines_, and _Springs_, that were
devised by Humane wit. To this end, he hath made a very curious _Survey_ of
all kinds of bodies, beginning with the _Point of a Needle_, and proceeding
to the _Microscopical_ view of the _Edges_ of _Rasors, Fine Lawn, Tabby,
Watered Silks, Glass-canes, Glass-drops, Fiery Sparks, Fantastical Colours,
Metalline Colours, the Figures of Sand, Gravel in Urine, Diamonds in
Flints, Frozen Figures, the Kettering Stone, Charcoal, Wood and other
Bodies petrified, the Pores of Cork, and of other substances, Vegetables
growing on blighted Leaves, Blew mould and Mushromes, Sponges, and other
Fibrous Bodies, Sea-weed, the Surfaces of some Leaves, the stinging points
of a Nettle, Cowage, the Beard of a wild Oate, the seed of the Corn-violet,
as also of Tyme, Poppy and Purslane._ He continues to describe _Hair, the
scales of a Soal, the sting of a Bee, Feathers_ in general, and in
particular those of _Peacocks; the feet of Flies; and other Insects; the
Wings and Head of a Fly; the Teeth of a Snail; the Eggs of Silk-worms; the
Blue Fly; a water Insect; the Tufted Gnat; a White Moth; the
Shepheards-spider; the Hunting Spider, the Ant; the wandring Mite; the
Crab-like insect, the Book-worm, the Flea, the Louse, Mites, Vine mites._
He concludeth with taking occasion to discourse of two or three very
considerable subjects, viz. _The inflexion of the Rays of Lights in the
Air; the Fixt stars; the Moon._

In representing these particulars to the Readers view, the Author hath not
only given proof of his singular skil in delineating all sorts of Bodies
(he having drawn all the _Schemes_ of these 60 _Microscopical_ objects with
his own hand) and of his extraordinary care of having them so curiously
engraven by the Masters of that Art; but he hath also suggested in the
several reflexions, made upon these Objects, such conjectures, as are
likely to excite and quicken the Philosophical heads to very noble
contemplations. Here are found inquiries concerning the _Propagation of
Light_ through {29} differing mediums; concerning _Gravity_, concerning the
_Roundness_ of Fruits, stones, and divers artificial bodies; concerning
_Springiness_ and _Tenacity_; concerning the _Original_ of _Fountains_;
concerning the _dissolution of Bodies into Liquors_; concerning
_Filtration_, and the ascent of Juices in Vegetables, and the use of their
_Pores_. Here an attempt is made of solving the strange _Phænomena_ of
_Glass-drops_; experiments are alleged to prove the _Expansion_ of _Glass_
by heat, and the _Contraction_ of _heated-Glass_ upon cooling; _Des Cartes_
his _Hypothesis of Colours_ is examined: the _cause of Colours_, most
likely to the Author, is explained: Reasons are produced, that _Reflection_
is not necessary to produce _colours_, nor a _double refraction_: some
considerable _Hypotheses_ are _offered_, for the explication of Light by
Motion; for the producing of all colours by Refraction; for reducing all
sorts of colours to two only, _Yellow_ and _Blew_; for making the _Air_, a
dissolvent of all _Combustible Bodies_: and for the explicating of all the
regular figures of _Salt_, where he alleges many notable instances of the
_Mathematicks_ of _Nature_, as having even in those things which we account
vile, rude & course, shewed abundance of curiosity and excellent _Geometry_
and _Mechanism_. And here he opens a large field for inquiries, and
proposeth Models for prosecuting them, 1. By making a full collection of
all the differing kinds of _Geometricall_ figur'd bodies; 2. By getting
with them an exact History of their places where they are generated or
found: 3. By making store of Tryals in Dissolutions and Coagulations of
several Crystallizing Salts: 4. By making trials on metalls, Minerals and
Stones, by dissolving them in severall _Menstruums_, and Crystallizing
them, to see what Figures will arise from those several compositums: 5. By
compounding & coagulating several Salts together into the same mass, to
observe the Figure of that product: 6. By inquiring the closenes or rarity
of the texture of those bodys by examining their gravity, and their
refraction, &c. 7. By examining what operations the fire hath upon several
kinds of Salts, what changes it causes in their figures, Textures, or {30}
Vertues. 8. By examining their manner of dissolution, or acting upon those
bodies dissoluble in them and the Texture of those bodies before and after
the process. 9. By considering, by what and how many means, such and such
figures, actions and effects could be produced, and which of them might be
the most likely, &c.

He goes on to offer his thoughts about the Pores of bodies, and a _kind_ of
_Valves_ in wood; about spontaneous generation arising from the
Putrefaction of bodies; about the nature of the Vegetation of mold,
mushromes, moss, spunges; to the last of which he scarce finds any Body
like it in texture. He adds, from the naturall contrivance, that is found
in the leaf of a Nettle, how the stinging pain is created, and thence takes
occasion to discourse of the poysoning of Darts. He subjoyns a curious
description of the shape, _Mechanism_ and use of the _sting_ of a _Bee_;
and shews the admirable Providence of Nature in the contrivance and fabrick
of _Feathers_ for Flying. He delivers those particulars about the Figure,
parts and use of the head, feet, and wings of a Fly, that are not common.
He observes the various wayes of the generations of Insects, and discourses
handsomely of the means, by which they seem to act so prudently. He taketh
notice of the _Mechanical_ reason of the _Spider's_ Fabrick, and maketh
pretty Observations on the hunting Spider, and other Spiders and their
Webs. And what he notes of a Flea, Louse, Mites, and Vinegar-worms, cannot
but exceedingly please the curious Reader.

Having dispatched these Matters, the Author offers his Thoughts for the
explicating of many _Phænomena_ of the Air, from the _Inflexion_, or from a
_Multiplicate Refraction_ of the rays of Light within the Body of the
_Atmosphere_, and not from a _Refraction_ caused by any terminating
_superficies_ of the Air above, nor from any such exactly defin'd
_superficies_ within the body of the _Atmosphere_; which conclusion he
grounds upon this, that a _medium_, whose parts are unequally _dense_, and
mov'd by various motions and transpositions as to one another, will produce
all these {31} visible effects upon the rays of Light, without any other
_coefficient_ cause: and then, that there is in the Air or _Atmosphere,
such_ a variety in the constituent parts of it, both as to their _density_
and _rarity_, and as to their divers mutations and positions one to
another.

He concludeth with two _Celestial Observations_; whereof the _one_ imports,
what multitudes of Stars are discoverable by the _Telescope_, and the
variety of their magnitudes; intimating with all, that the longer the
Glasses are, and the bigger apertures they will indure, the more fit they
are for these discoveries: the _other_ affords a description of a _Vale_ in
the _Moon_, compared with that of _Hevelius_ and _Ricciolo_; where the
Reader will find several curious and pleasant Annotations, about the Pits
of the _Moon_, and the Hills and Coverings of the same; as also about the
variations in the _Moon_, and its _gravitating_ principle, together with
the use, that may be made of this Instance of a gravity in the _Moon_.

As to the _Inventions of Art_, described in this Book, the curious Reader
will there find these following:

1. A _Baroscope_, or an Instrument to shew all the Minute Variations in the
_Pressure of the Air_; by which he affirms, that he finds, that before and
during the time of rainy weather, the Pressure of the Air is less; and in
dry weather, but especially when an _Easterly_ Wind (which having past over
vast Tracts of Land, is heavy with earthy particles) blows, it is much
more, though these changes be varied according to very odd Laws.

2. A _Hygroscope_, or an Instrument, whereby the _Watery steams_, volatile
in the Air, are discerned, which the Nose it self is not able to find.
Which is by him fully described in the Observation touching the _Beard of a
wild Oate_, by the means whereof this Instrument is contrived.

3. An Instrument for _graduating Thermometers_, to make them _Standards_ of
_Heat_ and _Cold_.

4. A _New Engine_ for _Grinding Optick Glasses_, by means of which he
hopes, that any Spherical Glasses, of what length {32} soever, may be
speedily made: which seems to him most easie, because, if it succeeds, with
one and the same Tool may be ground an _Object Glass_ of any length or
breadth requisite, and that with very little or no trouble in fitting the
_Engine_, and without much skill in the _Grinder_. He thinks it very exact,
because to the very last stroke the Glass does regulate and rectifie the
_Tool_ to its exact Figure; and the longer or more the _Tool_ and _Glass_
are wrought together, the more exact will both of them be of the desired
Figure. He affirms further, that the motions of the Glass and Tool do so
cross each other, that there is not one point of eithers surface, but hath
thousands of cross motions thwarting it, so that there can be no kind of
_Rings_ or _Gutters_ made, either in the _Tool_ or _Glass_.

5. A _New Instrument_, by which the _Refraction_ of all kinds of Liquors
may be exactly measured, thereby to give the Curious an opportunity of
making Trials of that kind, to establish the _Laws_ of _Refraction_, to
wit, whether the _Sines of the Angles of Refraction are respectively
proportionable to the Sines of the Angles of Incidence:_ This Instrument
being very proper to examine very accurately, and with little trouble, and
in small quantities, the _Refraction_ of any Liquor, not only for _one_
inclination, but for _all_; whereby he is enabled to make accurate
_Tables_. By the same also he affirms to have found it true, that what
_proportion_ the _Sine_ of the Angle of the one _inclination_ has to the
_Sine_ of its Angle of _Refraction_, correspondent to it, the same
proportion have all the other _Sines_ of Inclination to their respective
_Sines_ of _Refractions_.

Lastly, this Author despairs not that there may be found many Mechanical
Inventions, to improve our Senses of _Hearing, Smelling, Tasting,
Touching_, as well as we have improved that of _Seeing_ by _Optick
Glasses_.

       *       *       *       *       *


London, Printed with Licence for _John Martyn_, and _James Allestry_,
Printers to the _Royal Society_.

{33}

       *       *       *       *       *




_Numb._ 3.

PHILOSOPHICAL
_TRANSACTIONS._

       *       *       *       *       *

_Munday_, _May_ 8. 1665.

       *       *       *       *       *

The Contents.

    _Some Observations and Experiments upon _May-dew_. The Motion of the
    _Second Comet_ predicted, by the same person, who predicted that of the
    former. A Relation of the Advice, given by a _French_ Gentleman,
    touching the Conjunction of the _Ocean_ and the _Mediterranean_. Of the
    way of killing _Ratle-snakes_, used in _Virginia_. A Relation of
    Persons kill'd with Subterraneous _Damps_. Of the _Mineral_ of _Liege_,
    yielding both _Brimstone_, and _Vitriol_, and the way of extracting
    them out of it, used at _Liege_. An Account of Mr. _Boyle's_
    Experimental _History_ of_ Cold.

       *       *       *       *       *

_Some Observations and Experiments upon _May-Dew_._

That ingenious and inquisitive Gentleman, Master _Thomas Henshaw_, having
had occasion to make use of a great quantity of _May-dew_, did, by several
casual Essayes on that Subject, make the following Observations and Tryals,
and present them to the _Royal Society_. {34}

That _Dew_ newly gathered and filtred through a clean Linnen cloth, though
it be not very clear, is of a yellowish Colour, somewhat approaching to
that of Urine.

That having endevoured to putrefy it by putting several proportions into
Glass bodies with blind heads, and setting them in several heats, as of
dung, and gentle baths, he quite failed of his intention: for heat, though
never so gentle, did rather clarify, and preserve it sweet, though
continued for two moneths together, then cause any putrefaction or
separation of parts.

That exposing of it to the Sun for a whole Summer in Glasses, that hold
about two Gallons, with narrow mouths, that might be stopp'd with Cork, the
only considerable alteration, he observed to be produced in it, was, that
Store of green stuff (such as is seen in Summer in ditches and standing
waters) floated on the top, and in some places, grew to the sides of the
Glass.

That putting four or five Gallons of it into a half Tub, as they call it,
of Wood, and straining a Canvas over it, to keep out Dust and Insects, and
letting it stand in some shady room for three weeks or a month, it did of
itself putrefy and stink exceedingly, and let fall to the bottom a black
sediment like Mudd.

That, coming often to see, what Alterations appeared in the putrefaction,
He observed, that at the beginning, within twenty four hours, a slimy film
floated on the top of the water, which after a while falling to the bottom,
there came another such film in its place.

That if _Dew_ were put into a long narrow Vessel of Glass, such as formerly
were used for Receivers in distilling of _Aqua Fortis_, the slime would
rise to that height, that He could take it off with a Spoon; and when he
had put a pretty quantity of it into a drinking Glass, and that it had
stood all night, and the water dreined from it, if He had turned it out of
his hand, it would stand upright in figure of the Glass, in substance like
boyled white Starch, though something more transparent, if his memory
(_saith he_) fail him not.

That having once gotten a pretty quantity of this gelly, and put it into a
Glass body and Blind-head, He set it into a gentle {35} Bath with an
intention to have putrefied it, but after a few days He found, the head had
not been well luted on, and that some moisture exhaling, the gelly was
grown almost dry, and a large _Mushrom_ grown out of it within the Glass.
It was of a loose watrish contexture, such an one, as he had seen growing
out of rotten wood.

That having several Tubs with good quantity of _Dew_ in them, set to
putrefy in the manner abovesaid, and comming to pour out of one of them to
make use of it, He found in the water a great bunch, bigger than his fist,
of those Insects commonly called _Hog-lice_ or _Millepedes_, tangled
together by their long tailes, one of which came out of every one of their
bodies, about the bigness of a Horsehair: The Insects did all live and move
after they were taken out.

That emptying another Tub, whereon the Sun, it seems, had used sometimes to
shine, and finding, upon the straining it through a clean linnen cloth, two
or three spoonfulls of green stuff, though not so thick nor so green as
that above mentioned, found in the Glasses _purposely_ exposed to the Sun,
He put this green stuff in a Glass, and tyed a paper over it, and coming
some dayes after to view it, He found the Glass almost filled with an
innumerable Company of small Flyes, almost all wings, such as are usually
seen in great Swarms in the Aire in Summer Evenings.

That setting about a Gallon of this _Dew_ (which, he saith, if he
misremember not, had been first putrefied and strained) in an open
Jarre-Glass with a wide mouth, and leaving it for many weeks standing in a
South-window, on which the Sun lay very much, but the Casements were kept
close shut; after some time coming to take account of his _Dew_, He found
it very full of little Insects with great Heads and small tapering Bodies,
somewhat resembling Tadpoles, but very much less. These, on his approach to
the Glass, would sink down to the bottom, as it were to hide themselves,
and upon his retreat wrigle themselves up to the top of the water again.
Leaving it thus for some time longer, He afterwards found the room very
full of Gnats, though the Door and Windows were kept shut. He adds, that He
did not at first suspect, that those Gnats had any {36} relation to the
_Dew_, but after finding the Gnats to be multiplied and the little watry
Animals to be much lessened in quantity, and finding great numbers of their
empty skins floating on the face of his _Dew_, He thought, he had just
reason to perswade himself, the Gnats were by a second Birth produced of
those little Animals.

That vapouring away great quantities of his putrefied _Dew_ in Glass
Basons, and other Earthen glased Vessels, He did at last obtain, as he
remembers, above two pound of _Grayish Earth_, which when he had washed
with more of the same _Dew_ out of all his Basons into one, and vapoured to
siccity, lay in leaves one above another, not unlike to some kind of brown
Paper, but very friable.

That taking this Earth out, and after he had well ground it on a Marble,
and given it a smart Fire, in a coated Retort of Glass, it soon melted and
became a Cake in the bottom, when it was cold, and looked as if it had been
Salt and Brimstone in a certain proportion melted together; but, as he
remembers, was not at all inflamable. This ground again on a Marble, _he
saith_, did turn Spring water of a reddish purple Colour.

That by often calcining and filtring this Earth, He did at last extract
about two ounces of a fine small _white Salt_, which, looked on through a
good _Microscope_, seemed to have Sides and Angles in the same number and
figure, as _Rochpeeter_.

       *       *       *       *       *

_The Motion of the _Second_ Comet predicted, by the same Gentleman, who
predicted that of the _former_._

Monsieur _Auzout_, the same Person, that not long since communicated to the
World his _Ephemerides_ touching the course of the former _Comet_, and
recommended several Copies of them to the _Royal Society_, to compare their
Observations with his Account, and thereby, either to verifie his
Predictions, or to shew, wherein they differ, hath lately sent another
_Ephemerides_ concerning the Motion of the Second _Comet_, to the same end,
that invited him to send the other. {37}

In that Tract he observes, first in _General_, that this second _Comet_ is
contrary to the precedent, almost in all particulars: seeing that the
_former_ moved very swift, _this_, pretty slow; _that_ against the Order of
the signs from East to West, _this_, following them, from West to East:
_that_, from South to North, _this_, from North to South, as far as it hath
been hitherto, that we hear off, observed: _that_, on the side opposite to
the Sun, _this_, on the same side: _that_, having been in its _Perigee_ at
the time of its Opposition, _this_, having been there, out of the time of
its Conjunction: where he taketh also notice, that this _Comet_ differs in
brightness from the other, as well in its Body, which is far more vivid and
distinct, as in its _Train_, whose splendor is much greater, since it may
be seen even with great _Telescopes_, which were useless in the former, by
reason of its dimness. After this he descends to particulars, and informs
us, that he began to observe this Comet _April_ the second, and continued
for some days following, and that as soon as he had made three or four
Observations, he resolved to try again an _Ephemerides_; but that, having
no instruments exact enough, and the Comet being in a place, destitute of
Stars, and subject to Refractions, he feared to venture too much upon
Observations so neer one another, since in such matters a perfect exactness
is necessary, and wished to see some precedent Observations to direct him:
which having obtained, he thereby verified what he had begun, and resolved
to carry on his intended _Ephemerides_, especially being urged by his
Friends, and engaged by his former undertaking, that so it might not be
thought a meer hazard, that made him hit in the former; as also, that he
might try, whether his Method would succeed as well in slower, as in
swifter Comets, and in those, that are neer the Sun; as in such as are
opposite thereunto, to the end, that men might be advertised of the
_determination_ of its use, if it could not serve but in certain particular
Cases.

He relateth therefore, that he had finished this New _Ephemerides_ _April_
the sixth, and put it presently to the Press; in doing of which, he hopes,
he hath not disobliged the Publick: seeing that, though we should loose the
sight of this Star within a few days, by reason of its approach to the Sun,
yet having found, {38} that it is always to rise before the Sun, and that
we may again see it better, when it shall rise betimes, towards the end of
_May_, and in the beginning of _June_, if the cleerness of the Day-break
hinder us not; he thought it worth the while to try, whether the truth of
this _Ephemerides_ could be proved.

He affirms then, that the _Line_ described by this Star resembles hitherto
a _Great Circle_, as it is found in all other Comets in the midst of their
Course. He finds the said Circle inclined to the _Ecliptick_ about 26. d.
30'. and the _Nodes_, where it cuts it, towards the beginning of _Gemini_
and _Sagittary_; that it declines from the _Equator_ about 26. _d_ and cuts
it towards the 11. d. and consequently, that its greatest _Latitude_ hath
been towards _Pisces_, where it must have been _March_ 24. and its greatest
_Declination_, towards the 25 d. of the _Equator_, where it was to have
been _April_ 11.

He puts it in its _Perigee_ _March_ 27. about three of the Clock in the
Afternoon, when it was about the 15 degrees of _Pisces_, a little more
_Westerly_ then _Marshab_, or the _Wing_ of _Pegasus_, and that it was to
be in _Conjunction_ with the _Sun_, _April_ 9. Where yet he noteth, that
according to another Calculation, the _Perigee_ was _March_ 27. more
towards Night, so that the Comet advances a little more towards the _East_,
and retards towards the _West_; which not being very sensible in the first
days, differs more about the end, and in the beginning; which he leaves to
Observation.

He calculateth, that the greatest Motion it could make in one day, hath
been 4. d. and 8'. or 9'; in one hour, about 10'. and 25". so that its
_Diurnal Motion_ is to its last distance from the Earth a little more than
as 1. to 14. and its _Hourly Motion_, as 1. to 330.

He wonders, that it hath not been seen sooner; the first Observations that
he hath seen, but made by others, being of _March_ 17. Whereas he finds,
that it might have been seen since _January_, at least in the Months of
_February_ and _March_, when it rose at 2 of the Clock and before: because
it is very likely, that, considering its bigness and brightness, when it
was towards its _Perigee_, it was visible, since that towards the end of
_February_ it was not three times as much remote from the Earth, than when
it was in its _Perigee_, and that towards the end of _January_ it was not
five times as much. {39}

In the interim, _saith he_, the other _Comet_ could be seen with the naked
eye until _January_ 31. when it was more than ten times further remote,
than in its _Perigee_, although it was not by far so bright, nor its
streamer shining as this hath appeared.

He wishes, that all the changes that shall fall out in this _Comet_, might
be exactly observ'd; because of its not being swift, and the Motion of the
Earth very sensible, unless the _Comet_ be extreamly remote, we should find
much more light from this, than the former Star, about the Grand Question,
whether the _Earth_ moves or not; this Author having all along entertained
himself with the hopes, that the Motion of _Comets_ would evince, whether
the _Earth_ did move or not; and this very _Comet_ seemed to him to have by
design appeared for that end, if it had had more _Latitude_, and that
consequently we might have seen it before Day break. He wishes also, that,
if possible, it may be accurately observed, whether it will not a little
decline from its great Circle towards the _South_; Judging, that some
important truth may be thence deduced, as well as if its motion retarded
more, than the place of its _Perigee_ (which will be more exactly known
when all the passed Observations shall have been obtained) and its greatest
Motion do require.

He fears only, that it being then to rise at Break of Day, exact
Observations cannot be made of it: but he would, at least have it sought
with _Telescopes_, his _Ephemerides_ directing whereabout it is to be.

_April_ 10. it was to be over against the point of the _Triangle_, and from
thence more _Southerly_ by more than two degrees; and _April_ 11. over
against the bright Star of _Aries_, _April_ 17. over against the Stars of
the _Fly_, a little more _Southerly_, and _May_ 4 it is to be over against
the _Pleiades_, and about the fourth or fifth of the same Month, it is to
be once more in _Conjunction_ with the _Sun_; after which time, the _Sun_
will move from it _Eastward_, and leave it towards the _West_; which will
enable us to see it again at a better hour, provided the cleerness of the
Day-break be no impediment to us. He addeth, that this Star must have been
the third time in _Conjunction_ with the _Sun_, about the time when it
first began to appear: and foresees, that from all these particulars many
considerable consequences may be deduced. {40}

It will cut the _Ecliptick_ about the end of _July_, new Style, a little
more _Eastwards_ than the _Eye_ of _Taurus_; at which time there will be no
seeing of it, except it be with a _Telescope_.

It will be towards the _End_ of _April_, new style, twice as far distant as
it was in _Perigee_, thrice as far, _May_ the fourth, four times, _May_ the
eighteenth, and five times, _June_ the first, &c.

He would not have Men surprised, that there have been two _Comets_ within
so short a time; seeing, _saith he_, there were four, at least three, in
the Year 1618. and in other Years there have been two and more at the same
time. What he adds about their signification, we leave to _Astrologers_ to
dispute it with him. He concludeth with asking pardon, if he have committed
mistakes, which he hopeth he shall obtain the sooner, because of the small
time he hath had for these calculations; and he wishes that he could have
made all the Observations himself, seeing that it is easie to fail, when
one must trust to the Observations of others, whereof we know not the
exactness: where he instanceth, that according to his Observations, the way
of the _Comet_ should go neerer the Ecliptick than he hath marked it, even
without having any great regard to the Refractions: but since he would
subject himself to others, he hath made it pass a little higher, which, he
saith, was almost insensibly so, in those few days that he was observing
and writing, but that this may perhaps become sensible hereafter; which if
it be so, he affirms that it will cut the _Ecliptick_ and _Equator_ sooner,
than he hath marked it, &c. However, he thinks it convenient, to have given
aforehand a common Notion of what will become of a _Comet_, to prepare men
for all the Changes that may fall out concerning it: which he affirms he
hath endeavoured to do; the rest being easie to correct, as soon as any
good Observations, somewhat distant, have been obtained, considering, that
there need but two very exact ones, a little distant when the Star is not
swift, to trace its Way; although there must be at least three, to find out
all the rest. But, then would he have it considered, that although his
Method should be very exact, if there be not at hand Instruments big
enough, and Globes good enough to trust to, nothing can be done perfectly
in these kind of Predictions. {41}

       *       *       *       *       *

_A Relation of the advice given by Monsieur _Petit_, Intendant of the
Fortifications of _Normandy_, touching the Conjunction of the _Ocean_ and
_Mediterranean_._

This Intelligent Gentleman, Monsieur _Petit_, having been consulted with,
touching the Conjunction of the _Ocean_ and _Mediterranean_, delivers first
the Proposition, and then giveth his thoughts upon it.

The Proposition is, That there being about two Leagues below _Castres_ in
_Languedoc_ a Rivolet, called _Sor_, passing to _Revel_, there may by the
means thereof be made a Communication of the two Seas, by joyning the
Waters of this Rivolet by a Channel (to be kept full all the year long)
with those of St. _Papoul_, and others, which fall into _Fresqueil_
(another small River) that runs into the _Aude_ below _Carcassone_, and go
together to _Narbonne_, scituated upon the _Mediterranean_.

Having given the Proposition, he adds some particulars, to illustrate the
same, before he declares his judgment upon it. For he relateth, that there
is but one way, after the division of the Waters, to pass to the
_Mediterranean_, which is by a Rivolet, called _Fresqueil_, that is
conjoyn'd with the _Aude_: But, to pass to the _Ocean_, there are three;
One, by _Riege_, entring into the _Caronne_ above _Tholouse_; the other, by
_Lers_, passing on the side, and below the same Town; and the third, by
_Sor_, falling into the River _Agoust_ under _Castres_, afterwards into the
_Tarne_, and thence to _Montauban_, and lastly into the _Garonne_. And
that, to compass this design, all these Rivers and Rivolets are first to be
made Navigable unto their _Sluces_; that of _Aude_ and _Fresqueil_ for the
_Mediterranean_, and one of the others, such as shall be chosen, for the
_Ocean_. He addeth, that, as to the several Ways passing to the _Ocean_,
all of them commended as proper and convenient, and the three Countries
concerned therein, speaking every one for their advantage: Those of
_Castres_ and {42} _Montauban_, are for the River _Agoust_; those of
_Tholouse_, for _Riege_; and the rest, for _Lers_.

Now concerning his Opinion upon this Proposition, he thinks, that all that
hath been represented touching this matter, can signifie very little,
seeing that the main thing is wanting, which is the assurance, and certain
and positive mensuration of the height and quantity of the Waters,
necessary to fall into both the Channels of the _Aude_ and _Caronne_: that
there must be plenty of that, to furnish at all times and alwayes the
highest and first _sluces_, since what once issues thence, doth never enter
again into them; and after some Boats are passed, if there should not be a
sufficient supply for those that come after; either to go up, or to go
down, all would stand dry, and Merchants and their commodities would stay
long enough expecting the supply of Rains, to their great detriment. He
concludeth therefore, that no knowing and discreet Person is able, in
matters of this nature, to give a positive answer, without having before
him a large and exact Topographical Map of those places, and of the sources
of all the Rivolets, that are to supply the Water to the Head of the
pretended Channel, together with a full account of the survey and
mensuration of all the places, through which it is to pass; of the Nature
of the Ground, whether it be stony, sandy, rocky, &c. of the exact level of
all the places, where it is to be made, and of the several risings and
depressions thereof, to be assured that the Water may be conveyed to the
greatest rising, and to the highest _Sluce_; and lastly, of the quantity,
that may be had at high, middle, and low Water, to have enough for all
times; that all these things being first made out, 'tis then time enough to
judge of the possibility of the thing, and to calculate the charges
necessary for Execution.

This Artist having thus prudently waved this Proposition, diverts himself
with reflecting upon several others of the like nature, among which he
insists chiefly upon two, whereof one is that so much celebrated in
_Egypt_; the other, of _Germany_. And he is of Opinion, that the most
important of all is that, of conjoyning the _Red sea_ by the _Nile_ with
the _Mediterranean_, which he looks upon as the most excellent conveniency
to go into the _East Indies_ without doubling the _Cape of Good Hope_; and
yet it {43} could not be executed by those great Kings of _Egypt_, that
raised so many stupendious _Pyramids_; although in his Opinion the reasons
alleged by _Historians_ to justifie them for having abandoned that
undertaking are of no validity, and that the _Red Sea_ cannot be, as they
feared, higher than the _Nile_, and therefore not indanger the inundation
of _Egypt_.

The other Proposition was made to _Charles Magna_, _Anno_ 793. for joyning
the _Euxine_ Sea and the _Ocean_ together, by a Channel, which was begun
for that end, and designed to be 2000. paces long and 100. paces broad,
betwixt the River _Altmull_, falling into the _Danube_ above _Ratisbone_,
and the River _Rott_, passing at _Nurenberg_, and thence running into the
_Main_, and so into the _Rhine_. But yet this also proved abortive, though
there was great appearance of success at first.

       *       *       *       *       *

_Of the Way of killing _Ratle-Snakes_._

There being not long since occasion given at a meeting of the _Royal
Society_ to discourse of _Ratle Snakes_, that worthy and inquisitive
Gentleman, Captain _Silas Taylor_, related the manner, how they were killed
in _Virginia_, which he afterwards was pleased to give in writing, attested
by two credible persons in whose presence it was done; which is, as
follows.

The Wild _Penny-royal_ or _Ditany_ of _Virginia_, groweth streight up about
one foot high, with the leaves like _Penny-royal_, with little blue tufts
at the joyning of the branches to the Plant, the colour of the Leaves being
a reddish green, but the Water distilled, of the colour of Brandy, of a
fair Yellow: the Leaves of it bruised are very hot biting upon the Tongue:
and of these, so bruised, they took some, and having tyed them in the cleft
of a long stick, they held them to the Nose of the _Ratle-Snake_, who by
turning and wriggling laboured as much as she could to avoid it: but she
was killed with it, in less than half an hours time, and, as was supposed,
by the scent thereof; which was done _Anno_ 1657. in the Month of _July_,
at which season, they repute those creatures to be in the greatest vigour
for their poison. {44}

       *       *       *       *       *

_A Relation of Persons killed with subterraneous _Damps_._

This Relation was likewise made to the _Royal Society_, by that Eminent
_Virtuoso_ Sir _R. Moray_, who was pleased, upon their desire, to give it
them in writing; as followeth.

In a Coal-pit, belonging to the Lord _Sinclair_ in _Scotland_, where the
Coal is some 18 or 20 foot thick, and antiently wasted to a great depth:
The Colliers, some Weeks agoe, having wrought as deep as they could, and
being to remove into new Rooms (as they call them) did, by taking off, as
they retired, part of the Coal that was left as Pillars to support the Roof
and Earth over it, so much weaken them, that within a short space, after
they were gone out of the Pitt, the Pillars falling, the Earth above them
filled up the whole Space, where the Colliers had lately wrought, with its
ruins. The Colliers being here-by out of work, some of them adventured to
work upon old remains of Walls, so near the old wastes, that striking
through the slender partition of the Coal-wall, that seperated between them
and the place, where they used to work, they quickly perceived their
Errour, and fearing to be stifled by the bad Air, that they knew, possessed
these old wastes, in regard not onely of the Damps, which such wastes do
usually afford, but because there having for many years been a Fire in
those wastes, that filled them with stifling fumes and vapors, retired
immediately and saved themselves from the eruptions of the Damp. But next
day some seven or eight of them came no sooner so farr down the staires,
that led them to the place where they had been the day before, as they
intended, but upon their stepping into the place, where the Air was
infected, they fell down dead, as if they had been shott: And there being
amongst them one, whose Wife was informed he was stifled in that place, she
went down so far without inconvenience, that seeing her Husband near her,
ventured to go to him, but being choaked by the Damp, as soon as she came
near him, she fell down dead by him. {45}

This Story of Sir _R. Moray_ affirmed to have received from the _Earl_ of
_Weymes_, Brother in Law to the Lord _Sinclair_, as it was written to him
from _Scotland_.

       *       *       *       *       *

_Of the _Mineral_ of _Liege_, yeilding both _Brimstone_ and _Vitriol_, and
the way of extracting them out of it, used at _Liege_._

The Account of this _Mineral_, and of the way of extracting both
_Brimstone_ and _Vitriol_ out of it, was procured from _Liege_, by the
lately mentioned Sir _Robert Moray_ and by him communicated to the _Royal
Society_, as follows.

The _Mineral_, out of which _Brimstone_ and _Vitriol_ are extracted, is one
and the same, not much unlike Lead ore, having also oft times much Lead
mingled with it, which is seperated from it by picking it out of the rest.
The Mines resemble our _English_ Coal Mines dugg according to the depth of
the _Mineral_, 15, 20, or more fathoms, as the Vein leads the Workmen, or
the subterranean waters will give them leave, which in Summer so overflow
the Mines, that the upper waters, by reason of the drought, not sufficing
to make the Pumps goe, the Work ceases.

To make _Brimstone_, they break the Stone or Ore into small pieces, which
they put into Crucibles made of Earth, five foot long, square and
Pyramid-wise. The Entry is near a foot square. These Crucibles are laid
sloaping, eight undermost, and seven above them, as it were betwixt them,
that the Fire may come at them all, each having its particular Furnace or
Oven. The _Brimstone_ being dissolved by the violence of the heat, drops
out at the small end of the Crucible, and falls into a Leaden-Trough or
Receptacle, common to all the said Crucibles, through which there runs a
continual Rivolet of cold water, conveyed thither by Pipes for the cooling
of the dissolved Sulphur, which is ordinarily four hours in melting. This
done, the Ashes are drawn out by a crooked Iron, and being put into an Iron
Wheel barrow, are carried out of the Hutt, and {46} being laid in a heap,
are covered with other exiled or drained Ashes, the better to keep them
warm; which is reiterated, as long as they make _Brimstone_.

To make _Coperas_ or _Vitriol_, they take a quantity of the said Ashes, and
throwing them into a square planked pit in the Earth, some four foot deep,
and eight foot square, they cover the same with ordinary water, and let it
lye twenty four hours, or until an Egg will swim upon the liquor, which is
a sign, that it is strong enough. When they will boyl this, they let it run
through Pipes into the Kettles, adding to it half as much Mother-water,
which is that water, that remains after boyling of the hardned _Coperas_.
The Kettles are made of Lead, 4½ foot high, 6 foot long, and 3 foot broad,
standing upon thick Iron Barrs or Grates. In these the Liquor is boyled
with a strong Coal-fire, twenty four hours or more, according to the
strength or weakness of the Lee or Water. When it is come to a just
consistence, the fire is taken away, and the boyled liquor suffered to cool
somewhat, and then it is tapp'd out of the said Kettles, through holes
beneath in the sides of them, and conveyed through wooden Conduits into
several Receptacles, three foot deep and four foot long (made and ranged
not unlike our Tan-pits) where it remains fourteen or fifteen dayes, or so
long till the _Coperas_ separate it self from the water, and becomes icy
and hard. The remaining water is the above-mentioned Mother-water; and the
elixed or drained Ashes are the Dregs, or _Caput mortuum_, which the Lee,
whereof the _Vitriol_ is made, leaves behind it in the planked Pits.

       *       *       *       *       *

_A further Account of Mr. _Boyle_'s Experimental _History_ of _Cold_._

In the first Papers of these _Philosophical Transactions_, some promise was
made of a _fuller_ account, to be given by the next, of the _Experimental
History of Cold_, composed by the Honourable Mr. _Robert Boyle_; it being
then supposed, that this _History_ would have been altogether printed off
at the time of publishing the {47} _Second_ Papers of these _Transactions_;
but the Press, employed upon this Treatise, having been retarded somewhat
longer than was ghessed, the said promise could not be performed before
this time: wherein it now concerns the inquiring World to take notice, that
this subject, as it hath hitherto bin almost totally neglected, so it is
now, by this Excellent Author, in such a manner handled, and improved by
near _Two hundred_ choice _Experiments_ and _Observations_, that certainly
the _Curious_ and _Intelligent_ Reader will in the perusal thereof find
cause to admire both the Fertility of a Subject, seemingly so barren, and
the Author's Abilities of improving the same to so high a Degree.

But to take a short view of some of the particulars of this _History_, and
thereby to give occasion to _Philosophical_ men, to take this Subject more
into their consideration, than hitherto hath been done; the Ingenious
Readers will here see,

1, That not only all sorts of _Acid_ and _Alcalizate_ Salts, and Spirits,
even Spirit of Wine, but also Sugar, and Sugar of Lead mixed with Snow, are
capable of freezing other Bodies, and upon what account they are so.

2, That among the Substances capable of being frozen, there are not only
all gross sorts of Saline Bodies, but such also as are freed from their
grosser parts, not excepting Spirit of Urine, the _Lixivium_ of Pot-ashes,
nor Oyl of Tartar, _per deliquium_, it self.

3, That many very spiritous liquors, freed from their aqueous parts, cannot
be brought to freeze, neither naturally, nor artificially: And here is
occasionally mentioned a way of keeping _Moats_ unpassable in very cold
Countries, recorded by _Olaus Magnus_.

4, What are the ways proper to estimate the greater or lesser Coldness of
Bodies; and by what means we can measure the intensness of Cold produced by
Art, beyond that, which Nature needs to employ for the freezing of Water;
as also, in what proportion water of a moderate degree of Coldness will
{48} be made to _shrink_ by Snow and Salt, before it begin by Congelation
to _expand_ it self; and then, how to measure by the differing Weight and
Density of the same portion of Water, what change was produced in it,
betwixt the hottest time of Summer, and first glaciating degree of Cold,
and then the highest, which our Author could produce by _Art_: Where an
Inquiry is annex'd, whether the making of these kind of Tryals with the
waters of the particular Rivers and Seas, men are to sail on, may afford
any useful estimate, whether or not, and how much, ships may on those
waters be safely loaden more in Winter, than in Summer. To which is added
the way of making exact Discoveries of the differing degrees of Coldness in
differing Regions, by such Thermometers, as are not subject to the
alterations of the _Atmosphere's_ gravitation, nor to be frozen.

5. Whether, in Cold, the diffusion from Cold Bodies be made more strongly
downwards, contrary to that of Hot Bodies: Where is delivered a way of
freezing Liquors without danger of breaking the Vessel, by making them
begin to freeze at the bottom, not the top.

6. Whether that Tradition be true, that if frozen Apples or Eggs be thaw'd
neer the Fire, they will be thereby spoil'd, but if immersed in cold water,
the Internal Cold will be drawn out, as is supposed, by the External Cold;
and the frozen Bodies will be harmlesly thawed? _Item_, Whether Iron, or
other Metals, Glass, Stone, Cheese, &c. expos'd to the freezing Air, or
kept in Snow, or Salt, upon the immersing them in Water will produce any
Ice? _Item_, What use may be made of what happens in the different waies of
thawing Eggs and Apples, by applying the Observation to other Bodies, and
even to Men, dangerously nipp'd by excessive Cold. Where is added not only
a memorable Relation, how the whole Body of a Man was succesfully thawed
and cased all over with Ice, by being handled, as frozen Eggs and Apples
are; but also the Luciferousness of such Experiments, as these: and
likewise, what the effects of Cold may be, as to the Conservation or
Destruction of the Textures of Bodies: and in particular, how Meat and
Drink {49} may be kept good, in very Cold Countries, by keeping it under
Water, without glaciation? as also, how in extreme Cold Countries, the
Bodies of Dead Men and other Animals may be preserved very many years
entire and unputrified? And yet, how such Bodies, when unfrozen, will
appear quite vitiated by the excessive Cold? Where it is further inquired
into, whether some Plants, and other Medicinal things, that have specifique
Vertues, will loose them by being throughly congealed and (several wayes)
thawed? And also, whether frozen and thawed Harts-horn will yield the same
quantity and strength of Salt and saline Spirit, as when unfrozen? _Item_,
Whether the _Electrical_ faculty of _Amber_, and the _Attractive_ or
_Directive_ Virtue of _Loadstones_ will be either impaired, or any wayes
altered by intense Cold? This Head is concluded by some considerable
remarks touching the operation of Cold upon Bones, Steel, Brass, Wood,
Bricks.

7, What Bodies are expanded by being frozen, and how that expansion is
evinced? And whether it is caused by the intrusion of Air? As also,
whether, what is contained in icy bubbles, is true and Springy Air, or not.

8, What Bodies they are, that are contracted by Cold; and how that
Contraction is evinced? Where 'tis inquired, whether _Chymical Oyles_ will,
by Congelation, be like expressed Oyls, contracted, or, like aqueous
Liquors, expanded?

9, What are the wayes of _Measuring_ the _Quantity_ of the Expansion and
Contraction of Liquors by Cold? And how the Author's account of this matter
agrees with what Navigators into cold Climats, mention from experience,
touching pieces of Ice as high as the Masts of their Ships, and yet the
Depth of these pieces seems not at all answerable to what it may be
supposed to be.

10, How strong the Expansion of freezing water is? Where are enumerated the
several sorts of Vessels, which being filled {50} with water, and exposed
to the cold Air, do burst; and where also the weight is expressed, that
will be removed by the expansive force of Freezing? Whereunto an Inquiry is
subjoyned, whence this prodigious force, observed in water, expanded by
Glaciation, should proceed? And whether this _Phænomenon_ may be solved,
either by the _Cartesian_, or _Epicurean_ Hypothesis?

11, What is the _Sphere of Activity_ of Cold, or the Space, to whose
extremities every way the Action of a cold Body is able to reach: where the
difficulty of determining these limits, together with the causes thereof,
being with much circumspection mentioned, it is observed, that the _Sphere
of Activity_ of Cold is exceeding narrow, not only in comparison of that of
Heat in Fire, but in comparison of, as it were, the _Atmosphere_ of many
odorous Bodies; and even in comparison of the _Sphere of Activity_ of the
more vigorous Loadstones, insomuch, that the Author hath doubted, whether
the Sense could discern a Cold Body, otherwise then by immediate Contract.
Where several Experiments are delivered for the examining of this matter,
together with a curious relation of the way used in _Persia_, though a very
hot Climate, to furnish their _Conservatories_ with solid pieces of Ice of
a considerable thickness: To which is added an Observation, how far in
Earth and Water the Frost will pierce downwards, and upon what accounts the
deepness of the Frost may vary. After which, the care is inculcated, that
must be had, in examining, whether Cold may be diffused through all
_Mediums_ indefinitely, not to make the Trials with _Mediums_ of two great
thickness: where it is made to appear, that Cold is able to operate through
Metalline Vessels, which is confirmed by a very pretty Experiment of making
_Icy Cups_ to drink in, whereof the way is accurately set down. Then are
related the Trials, whether, or how, Cold will be diffused through a
_Medium_, that _some_ would think a _Vacuum_, and which to _others_ would
seem much less disposed to assist the diffusion of Cold, than Common Air it
self. After which follows a curious Experiment, shewing whether a Cold Body
can operate through {51} a _Medium_ actually hot, and having its heat
continually renewed by a fountain of heat.

12, How to estimate the solidity of the Body of Ice, or how strong is the
mutual adhesion of its parts? and whether differing Degrees of Cold may not
vary the Degree of the compactness of Ice. And our Author having proceeded
as far as he was able towards the bringing the strength of Ice to some
Estimate by several experiments, he communicateth the information, he could
get about this matter among the Descriptions that are given us of cold
Regions: and then he relateth out of Sea-mens _Journals_, their
Observations touching the insipidness of resolved Ice made of Sea-water;
and the prodigious bigness of it, extending even to the height of two
hundred and forty Foot above water, and the length of above eight Leagues.
To which he adds some promiscuous, but very notable Observations concerning
Ice, not so readily reducible to the foregoing Heads: _videlicet_, Of the
blew colour of Rocky pieces of Ice; and the horrid noise made by the
breaking of Ice, like that of Thunder and Earthquakes, together with a
Consideration of the cause, whence those loud Ruptures may proceed.

13, How Ice and Snow may be made to last long; and what Liquor dissolves
Ice sooner than others, and in what proportion of quickness the Solutions
in the several Liquors are made, where occasion is offered to the Author,
to examine, whether Motion will impart a heat to Ice? After which he
relates an Experiment of _Heating_ a _Cold_ Liquor with Ice, made by
himself in the presence of a great and Learned Nobleman, and his Lady, who
found the Glass wherein the Liquor was, so hot that they could not endure
to hold it in their Hands. Next it is examined, whether the effects of Cold
do continually depend upon the actual presence and influence of the
manifest Efficient causes, as the Light of the Air depends upon the Sun or
Fire, or other Luminous Bodies. To this is annexed an Account of the
_Italian_ way of making _Conservatories_ of Ice and Snow, as the Author had
received it from that Ingenious and Polite Gentleman, Master _J. Evelyn_.
{52}

But want of time prohibiting the accomplishment of the intended account of
this Rich Piece: what remains, must be referred to the next Occasion. It
shall only be intimated for a Conclusion, that the _Author_ hath annexed to
this _Treatise_, an Examen of Master _Hob_'s Doctrine touching _Cold_;
wherein the _Grand_ Cause of _Cold_ and its Effects is assigned to _Wind_,
in so much that 'tis affirmed, that almost any Ventilation and stirring of
the Air doth refrigerate.

       *       *       *       *       *


_LONDON,_

Printed with Licence, By _John Martyn_, and _James Allestry_, Printers to
the _Royal-Society_, 1665

{53}

       *       *       *       *       *




_Numb._ 4.

PHILOSOPHICAL
_TRANSACTIONS._

       *       *       *       *       *

_Munday_, _June_ 5. 1665.

       *       *       *       *       *

The Contents.

    _A Relation of some extraordinary Tydes in the _West Isles_ of
    _Scotland_, by Sr. _Robert Moray_. The judgment of Monsieur _Auzout_,
    touching the _Apertures_ of _Object-glasses_, and their _proportions_
    in respect of the several lengths of _Telescopes_; together with a
    _Table_ thereof. Considerations of the same Person upon Mr. _Hook's_
    New Engine for grinding of _Optick-glasses_. Mr. _Hook's_ Thoughts
    thereupon. Of a means to illuminate an _Object_ in what proportion one
    pleaseth; and of the _distances_, that are requisite to burn Bodies by
    the _Sun_. A further accompt by Monsieur _Auzout_ of Signior
    _Campani_'s Book, and Performances about _Optick-Glasses_. _Campani_'s
    Answer thereunto; and Mr. _Auzout_'s Animadversions upon that Answer.
    An accompt of Mr. _Lower_'s newly published _Vindication_ of Dr.
    _Willis_'s Diatriba de _Febribus_._

       *       *       *       *       *

_A Relation of some extraordinary Tydes in the West-Isles of _Scotland_, as
it was communicated by Sr. _Robert Moray_._

In that Tract of _Isles_, on the West of _Scotland_, called by the
Inhabitants, the _Long-Island_, as being about 100. miles long from _North_
to _South_, there is a multitude of small Islands, situated in a _Fretum_,
or _Frith_, that passes between the Island of _Eust_, and the _Herris_;
amongst which, there is one called _Berneray_, some three miles long, and
{54} more than a mile broad, the length running from _East_ to _West_, as
the _Frith_ lyes. At the _East_ end of this _Island_, where I stayed some
16. or 17. dayes, I _observed_ a very strange Reciprocation of the Flux and
Re-flux of the Sea, and _heard_ of another, no less remarkable.

Upon the _West_ side of the _Long Island_, the Tides, which came from the
_South-west_, run along the Coast, _Northward_; so that during the ordinary
course of the Tides, the Flood runs _East_ in the _Frith_, where _Berneray_
lyes, and the Ebb _West_. And thus the Sea ebbs and flows orderly, some 4.
days before the _full Moon_, and _change_, and as long after (the ordinary
Spring-tides rising some 14. or 15. foot upright, and all the rest
proportionably, as in other places). But afterwards, some 4. days before
the _Quarter-moons_, and as long after, there is constantly a great and
singular _variation_. For _then_, (a _Southerly_ Moon making there the full
Sea) the course of the Tide being _Eastward_, when it begins to flow, which
is about 9½ of the Clock, not onely continues so till about 3½ in the
afternoon, that it be high water, but, after it begins to ebb, the Current
runs on still _Eastward_, during the whole Ebb; so that it runs _Eastward_
12 hours together, that is, all day long, from about 9½ in the morning, til
about 9½ at night. But then, when the night-Tide begins to flow, the
Current turns, and runs _Westward_ all night, during both Floud & Ebb, for
some 12. hours more, as it did _Eastward_ the day before. And thus the
Reciprocations continue, one Floud and Ebb, running 12 hours _Eastward_,
and another twelve hours _Westward_, till 4. days before the _New_ and
_Full_ Moon; and then they resume their ordinary regular course as before,
running _East_, during the six hours of Floud, and _West_, during the six
of Ebb. And this I observed curiously, during my abode upon the place,
which was in the Moneth of _August_, as I remember.

But the Gentleman, to whom the _Island_ belongs at present, and divers of
his Brothers and Friends, knowing and discreet persons, and expert in all
such parts of Sea-matters, as other _Islanders_ commonly are, though I
shrewdly suspected their skill in Tides, when I had not yet seen what they
told me, and I have now related of these irregular Courses of the Tides,
did most confidently assure me, and so did every body I spake with {55}
about it, that there is yet another irregularity in the Tides, which never
fails, and is no less extraordinary, than what I have been mentioning:
which is, That, whereas between the _Vernal_ and _Autumnal Equinoxes_, that
is, for six Moneths together, the Course of irregular Tides about the
Quartermoons, is, to run all day, that is, twelve hours, as from about 9½
to 9½, 10¼ to 10¼ _&c. Eastward_, and all night, that is, twelve hours
more, _Westward_: during the other six Moneths, from the _Autumnal_ to the
_Vernal Equinox_, the Current runs all day _Westward_, and all Night
_Eastward_.

Of this, though I had not the opportunity to be an Eye-witness, as of the
other, yet I do not at all doubt, having received so credible Information
of it.

To penetrate into the _Causes_ of these strange Reciprocations of the
Tides, would require exact descriptions of the Situation, Shape, and Extent
of every piece of the adjacent Coasts of _Eust_ and _Herris_; the Rocks,
Sands, Shelves, Promontorys, Bays, Lakes, Depths, and other Circumstances
which I cannot now set down with any certainty, or accurateness; seeing,
they are to be found in no _Map_, neither had I any opportunity to survey
them; nor do they now occur to my Memory, as they did some years ago, when
upon occasion I ventured to make a _Map_ of this whole _Frith_ of
_Berneray_, which not having copied, I cannot adventure to beat it out
again.

       *       *       *       *       *

__Monsieur Auzout_'s Judgment touching the Apertures of _Object-Glasses_,
and their _Proportions_, in respect of the several _Lengths_ of
_Telescopes_._

This Author, observing in a small _French Tract_ lately written by him to a
Countryman of his, Monsieur _L' Abbe Charles_; That great _Optick Glasses_
have almost never as great an _Aperture_ as the small ones, in proportion
to what they Magnifie, and that therefore they must be more dim; takes
occasion to inform {56} the _Reader_, that he hath found, that the
_Apertures_, which _Optick-Glasses_ can bear with distinctness, are in
about a _subduplicate proportion_ to their _Lengths_; whereof he tells us
he intends to give the reason and demonstration in his _Diopticks_, which
he is now writing, and intends to finish, as soon as his Health will
permit. In the mean time, he presents the _Reader_ with a _Table_ of such
_Apertures_; which is here exhibited to the Consideration of the Ingenious,
there being of this _French_ Book but one Copy, that is known, in
_England_.

A _TABLE_ of the _Apertures_ of _Object-Glasses_.

_The Points put to some of these Numbers denote Fractions._

   Lengths of  |For excellent|  For good   |For ordinary |
    Glasses.   |    ones.    |    ones.    |    ones.    |
  Feet, Inches.|Inch,  Lines.|Inch,  Lines.|Inch,  Lines.|
               |             |             |             |
              4|           4.|            4|            3|
              6|           5.|            5|            4|
              9|            7|            6|            5|
    1         0|           8.|            7|            6|
  -------------|-------------|-------------|-------------|
    1         6|            9|           8.|            7|
    2         0|           11|           10|            8|
    2         6|1           0|           11|            9|
    3         0|1           1|1           0|           10|
  -------------|-------------|-------------|-------------|
    3         6|1          2.|1           1|           11|
    4         0|1           4|1           2|1           0|
    4         6|1           5|1           3|1           .|
    5         0|1           6|1           4|1          1.|
  -------------|-------------|-------------|-------------|
    6          |1          7.|1           5|1           2|
    7          |1           9|1           6|1           3|
    8          |1          10|1           8|1           4|
    9          |1         11.|1           9|1           5|
  -------------|-------------|-------------|-------------|
    10         |2           1|1          10|1           6|
    12         |2           4|2           0|1           8|
    14         |2           6|2           2|1          9.|
    16         |2           8|2           4|1         11.|
    18         |2          10|2           6|2           1|
    20         |3           0|2           7|2          2.|
  -------------|-------------|-------------|-------------|
    25         |3           4|2          10|2          4.|
    30         |3           8|3           2|2           7|
    35         |4           0|3          4.|2          10|
    40         |4           3|3           7|3           .|
  -------------|-------------|-------------|-------------|
    45         |4           6|3          10|3          2.|
    50         |4           9|4           0|3          4.|
    55         |5           0|4           3|3          6.|
    60         |5           2|4           6|3          8.|
  -------------|-------------|-------------|-------------|
    65         |5           4|4           8|3          10|
    70         |5           7|4          10|4           .|
    75         |5           9|5           0|4          2.|
    80         |5          11|5           2|4           5|
  -------------|-------------|-------------|-------------|
    90         |6           4|5           6|4          7.|
    100        |6           8|5           9|4          10|
    120        |7           5|6           5|5           3|
    150        |8           0|7           0|5          11|
  -------------|-------------|-------------|-------------|
    200        |9           6|8           0|6           9|
    250        |10          6|9           2|7          8.|
    300        |11          6|10          0|8           5|
    350        |12        *6.|10          9|9           0|
    400        |13          4|11          6|9           8|
  -------------+-------------+-------------+-------------+



{57}

       *       *       *       *       *

_Considerations of Monsieur _Auzout_ upon Mr. _Hook_'s New Instrument for
Grinding of _Optick-Glasses_._

In the above-mentioned _French_ Tract, there are, besides several other
particulars, to be represented in due place, contained some
_Considerations_ of Monsieur _Auzout_ upon Mr. _Hook_'s New _Engine_ for
grinding _Optick-Glasses_. Where he premises in _General_ his thoughts
touching the working of _Great_ Optick-Glasses, and that by the help of a
_Turn lathe_; affirming first of all, that not only the _Engin_ is to be
considered for giveing the _Figure_, but the _Matter_ also, which ought to
be brought to greater perfection, than it hath been hitherto. For, he finds
it not so easie (as least, _where he is_) to procure _Great_ pieces of
Glass without _Veins_, and other faults, nor to get such, as are thick
enough without _Blebbs_; which, if they be not, they will yield to the
pressure and weight, either when they are fitted to the _Cement_, or
wrought.

Secondly, He finds it difficult to work these _Great_ Glasses of the _same_
thickness, which yet is very necessary, because, that the least difference
in _Figures_ so little _convex_, can put the _Center_ out of the _Midle_, 2
or 3 _Inches_; and if they be wrought in _Moulds_, the length of time,
which is required to wear and to smooth them, may spoil the best _Mould_,
before they be finished. Besides, that the strength of Man is so limited,
that he is unable to work Glasses beyond a certain bigness, so as to finish
and polish them all over so well, as _small_ Glasses; whereas yet, the
bigger they are, the more compleat they ought to be: And if any weight or
Engine be used to supply strength, there is then danger of an unequal
pressure, and of wearing away the Engine; In the mean time, the preciseness
and delicateness is {58} greater than can easily be imagined. Wherefore he
could never, having some experience of this preciseness, conceive, that a
_Turn-lathe_, wherein must be two different, and in some manner contrary
motions, can move with that exactness and steddiness, that is required,
especially, for any considerable length of time.

Having premised this, he discourses upon Mr. _Hook_ his _Turne_, intimating
first of all, that he was impatient to know what kind of _Turne_ this was,
imagining, that it had been tried, and had succeeded, as coming from a
Society that professeth, they publish nothing but what hath been maturely
examin'd. But that he was much surprised when he saw the _Micrography_ of
Mr. _Hook_, and found there, that his _Engine_ was published upon a _meer
Theory_, without having made any Experiment, though that might have been
made with little charge and great speed; expence of Money and Time being
the onely thing, that can excuse those who in matter of _Engines_ impart
their inventions to the publick, without having tried them, to excite
others to make trial thereof.

Whereupon he proposes some difficulties, to give the _Inventor_ occasion to
find a way to remove them. He affirms therefore, that though it be true in
the _Theory_, that a _Circle_, whose _Plain_ is inclined to the _Axis_ of
the _Sphere_ by an _Angle_, whereof half the _Diameter_ is the _Sine_, and
which touches the _Sphere_ in its _Pole_, will touch in all its parts a
_spherical Surface_, that shall turn upon that _Axe_. But that it is true
also, that that must be but a _Mathematical Circle_, and without _Breadth_,
and which precisely touches the Body in its middle: Whereas in the
practice, a _Circle_ capable to keep Sand and Putty, must be of some
_breadth_; and he knows not whether we can find such a dexterity of keeping
so much of it, and for so long a time, as needs, upon the Brim of a _Ring_
that is half an Inch broad. He adds, that it is very difficult to contrive,
that the middle of the Glass do always precisely answer to the Brim of this
_Ring_, seeing that the position of the Glass does always change a little
in respect of the _Ring_, in proportion as 'tis worn, and as it must be
pressed because of its inclination. He believes it also very hard, to give
to the _Axis_ or to the _Mandril_, which holds the Glass, that little {59}
_Inclination_, that would be necessary for great Glasses, and to make the
two _Mandrils_ to have one and the same _Plain_, as is necessary. And,
having done all this, he persuades himself, that it is exceedingly
difficult, if not impossible, for two contrary motions, where so many
pieces are, to rest for a long time steddy and firm, as is requisite for
the not swarving from it a hair's thickness, since less than that can
change all.

He goes on, and, seeing that this _Inventor_ speaks of Glasses of a
thousand, & ten thousand foot, which he supposed not impossible to be made
by this _Engine_, discourses of what is necessary for the making Glasses of
such bignesses; which he believes this _Inventor_ may perhaps not have
thought of. Wherefore he affirms, that if the _Table_, made by himself for
the _Apertures_ of Glasses (which is that, that is above delivered) be
continued unto a thousand feet, by taking always the _Subduplicate
proportion_ of _Lengths_, it will be found, that for pretty good ones, the
_Aperture_ must be of 15. Inches; for good ones, more than 18. and for such
as are excellent, more than 21. Inches: whence it may be judged, what piece
of Glass, and of what thickness it must be, to endure the working. But he
proceeds to speak of the _Inclination_, which the _Mandril_ must have upon
the _Plain_ of the _Ring_, when the _Ring_ should have 10. or 12 Inches;
and finds, that it would make but 6 or 7. minutes of inclination, and that
a Glass would have less _Convexity_, and consequently, less difference from
a Glass perfectly plain, than the 7. or 8. part of a Line. And then he
leaveth it to be judged, whether a Glass of such a Length being found, we
ought to hope, that a _Turn_ can be firm enough to keep such a piece of
Glass in the same Inclination, so that a _Mandril_ do not recede some
Minutes from it: and, though even the Glass could be fastned perfectly
perpendicular to the _Mandril_, that those two _Mandrils_ could be put in
one and the same Plain, & that that little Inclination, which is requisite,
could be given, and the _Mandril_ be continued to be pressed in that same
_Inclination_, according as the Glass is worn. All which particulars, he
conceives to be very hard in the practice; not to mention, that the weight
of the Glass, that should be inclined to the _Horizon_, as 'tis represented
by Mr. _Hook_, would make it slide upon the _Cement_, and so {60} change
the _Center_; and that the Glass is not pressed at the same time by the
_Ring_ but in one part on the side, _vid._ about a fourth; and that the
parts of the Glass are not equally worn away, &c. What then, _saith he_,
would becom of a Glass of 10000 feet, which, according to the said Table,
would have more than four feet, or four feet and nine inches, or five feet,
seven inches _Aperture_, and of which the _Ring_, though it were two feet
nine inches, would have but one minut of _Inclination_, and the Glass of 5
feet _Aperture_ would have but 4 minuts, and the curvity of it would be
less than the eight part of a Line.

But, _saith he_, let us consider, only a Glass of 300 foot, to see, what is
to be hoped of that, and to know at least the difficulty, to be met with in
making a Glass only of that Length. A Glass then of 300 foot, according to
his Table, must have more than 8 inches _Aperture_, which maketh but 16
minuts of its _Circle_, and it should have more than 11 inches, if it be an
excellent one. If Mr. _Hook_ (adds he) did use but his _Ring_ of 6 inches,
which he would use from twelve to an hundred foot Glass, the _Inclination_,
which the _Axis_, or _Mandril_, that bears his Glass, should have, should
be but 16 minuts, and the _Curvity_ of the Glass would be less than the
eighth part of a Line, and if he should use a bigger, the _Inclination_
would be proportionable.

Whence it may be judged (continues he) that we are yet very far from seeing
_Animals &c._ in the _Moon_, as Monsieur _Des Cartes_ gave hope, and Mr.
_Hook_ despairs not of. For, he believes by what he knows of _Telescopes_,
that we are not to look for any above 300 or 400 foot at most; and he
fears, that neither _Matter_ nor _Art_ will go even so far.

When therefore (_saith he_) a Glass of 300 foot should bear an Eye-glass of
6 inches (which would appear wonderful) it would magnifie but 600. times in
_Diameter_, that is, 360000 times in _Surface_: but suppose, that such
could be made, as would magnifie a 1000 times in _Diameter_, and 1000000.
of times in _Surface_, admitting there were but 60000 leagues from the
_Earth_ to the _Moon_, and that the smalness of the _Aperture_ of the
Glasses (which yet would diminish the Light more than 36 times) and the
obstacle of the Air were not considered, we should not {61} see the _Moon_,
but as if we were a 100, or at least, 60. leagues distant from her without
a Glass. He here wishes, that those, that promise to make us see _Animals_
and _Plants_ in the Moon, had thought on what our naked Eyes can make us
discern of such Objects, only at 10 or 12 leagues distance.

But this he would not have understood as a discouragement from searching
with all care and earnestness after the means of making long _Telescopes_,
or of facilitating the working thereof; but only as an Advertisement to
those, who light upon the _Theory_ of any _Engine_, not to expose it
presently as possible and useful, before they have tried it, or if it have
succeeded in small, not to endeavour to persuade, that it will also succeed
in great.

As it may happen (_saith he_) that the Engin of Mr. _Hook_ may, by using
all necessary precautions, succeed in the making of _Eye-Glasses_, or
_small_ Optick-Glasses, but not in making _great_ ones; as we see, that an
instrument composed of two Rulers, wherewith are traced Portions of
Circles, succeeds well enough in _small_, but when there is no more than
half a Line, a quarter of a Line, or less convexity, it will be no longer
just at all, as he tells us to have made the proof of it in Circles drawn
by the means of one of these Instruments, made by one of the best Workmen
in his time, who, whilst he lived, esteemed them above price, although they
be not just; as others and my self (_saith he_) have by tryal found, when
we endeavoured to make _Moulds_ by their means, & as those, who by the like
Instrument laboured to trace portions of Circles of 80 or 100 foot, _&c.
Diameter_, can attest.

But, notwithstanding all this, he hath thought upon two or three things,
which he thinks may remedy some inconveniencies of Mr. _Hook_ his _Turn_.
The _first_ is, to invert the Glass, and to put it under the _Ring_, that
so not only the Glass may be placed more _Horizontally_, and not slide upon
the _Cement_, but that the _Sand_ also, and the _Putty_ may stay upon the
Glass.

The _other_ is, that there must be two _Poppetheads_, into which the
_Mandril_ must pass, where the _Ring_ is to be fastned; and the _Mandril_
must be perfectly _Cylindrical_, that so it may advance upon the Glass as
it wears away by the means of its weight, or by the means of a spring,
pressing it, without wrigling from one place to another, as it would
presently happen in the fashion, {62} as the _Turn_ is composed. For, when
the Glasses do wear, especially when they are very _convex_, it cannot be
otherwise, but the _Mandril_ will play and wrigle, before the _Scrue_ be
made firm.

But he doubts, whether all can be remedied, which he leavs to the industry
of Mr. _Hook_, considering what he saith in the _Preface_ of his
_Micrography_, touching a Method, he knows, of finding out as much in
_Mechanicks_, as can be found in _Geometry_ by _Algebra_.

Besides this, he taketh notice, that most of those that medle with
_Optick-Glasses_, give them not as much _Aperture_, nor charge them so deep
as they ought. And he instances in the _Telescope_, which His _Majesty_ of
_Great Britain_ presented the _Duke_ of _Orleans_ with, _videl._ that it
did bear but 2 inches, and 9 lines _French_, for its greatest _Aperture_,
though there be 5 or 6 lesser _Apertures_, of which it seems (_saith he_)
the Artificer would have those, that use it, serve themselves more
ordinarily, than of the greatest; which conveys but almost half as many
Rays as it should do, according to his Calculation, which is, as 9 to 16;
Whereas, according to his _Table_ of _Apertures_, an excellent 35 foot
_Telescope_ should bear 4 inches _Aperture_ in proportion to _excellent_
small ones. He notes also, that the Eye-glass of the said _Telescope_,
composed of 2 Glasses, hath no more effect, when it is most charged, than a
Glass of 4½ inches; which makes it magnifie not a 100 times. And he finds
by Mr. _Hook_, that he esteems a _Telescope_ made in _London_ of 60 feet,
(which amount to about 57 feet of _France_, the foot of _France_ being to
that of _England_ as about 15 to 16) because it can bear at least 3
_English_ inches _Aperture_, and that there are few of 30 feet, that can
bear more than 2 inches, (which is but 22½ Lines _French_) although he (M.
_Auzout_) gives no less _Aperture_ than so, to a 15 foot-_Telescope_, and
his of 21 feet hath ordinarily 2 Inches, 4 Lines, or 2 inches, 6 Lines
_Aperture_.

This Discourse he Concludeth with exhorting those, that work
_Optick-Glasses_, to endeavor to make them such, that they may bear great
_Apertures_ and deep Eye-glasses; seeing it is not the length that gives
esteem to _Telescopes_; but on the contrary renders them less estimable, by
reason of the trouble {63} accompanying them, if they perform no more, than
shorter ones. Where, by the by, he takes notice, that he knows not yet,
what _Aperture_ Signor _Campani_ gives to his Glasses, seeing he hath as
yet signified nothing of it; but that the small one, sent by him to
Cardinal _Antonio_, hath no more _Aperture_, than ordinary ones ought to
have.

He promises withall, that he will explicate this way in his _Treatise of
the usefulness of Telescopes_, where he intends to assign the Bigness of
the _Diameter_ of all the _Planets_, and their proportion to that of the
_Sun_; as also, that of the _Stars_, which he esteems yet much less, than
all those have done, that have written of it hitherto; not believing, that
the _Great Dog_, which appears to be the fairest Star of the _Firmament_,
hath 2 _Seconds_ in _Diameter_, nor that those, which are counted of the
sixth Magnitude, have 20 _thirds_; nor thinking, that all the Stars, that
are in the _Firmament_, do enlighten the Earth as much as a Luminous Body
of 20 _seconds_ in _Diameter_ would do, or, because there is but one half
of them at the same time above our _Horizon_, as a Body of 14 _seconds_ in
_Diameter_; and as the 18432^{th} part of the _Sun_ would enlighten us, or
as the _Sun_ would do, if we were 14 times more distant from it, than
_Saturn_, and 137 times further, than the Earth: Which, _he saith_, would
not be credible, if he did not endeavor to evince it both by _Experience_
and _Reason_. And he doubts not, but that _Venus_, although she sends us no
Light but what is reflected, does sometimes enlighten the _Earth_ more,
than all the Stars together. Yet he would not have us imagine, from what he
hath spoken of the smallness of the Stars, that _Telescopes_ do not
magnifie them by reason of their great distance, as they do _Planets_; for
this he judgeth a Vulgar Error, to be renounced. _Telescopes_ magnifie the
_Stars_ (_saith he_) as much in proportion, as they do all other Bodies,
seeing that the demonstration of their magnifying is made even upon
_Parallel_ rays, which do suppose an infinite distance, though the Stars
have none such: And if the _Telescopes_ did not magnifie the Stars, how
could they make us see some of the _fiftieth_, and it may be some of the
_hundreth_, and _twohundreth_ Magnitude, as they do, and as they would shew
yet much lesser ones, if they did magnifie more? {64}

       *       *       *       *       *

__M^r. Hook_'s Answer to Monsieur _Auzout_'s Considerations, in a Letter to
the Publisher of these _Transactions_._

  _SIR_,

Together with my most hearty thanks for the favour you were pleased to do
me, in sending me an _Epitome_ of what had been by the ingenious Monsieur
_Auzout_ animadverted on a description, I had made of an _Engine_ for
_grinding spherical Glasses_, I thought my self obliged, both for your
satisfaction, and my own Vindication, to return you my present thoughts
upon those Objections. The chief of which seems to be against the very
_Proposition_ it self: For it appears, that the _Objector_ is somewhat
unsatisfied, that I should propound a thing in _Theory_, without having
first tried the _Practicableness_ of it. But first, I could wish that this
worthy Person had rectified my mistakes, not by speculation, but by
experiments. Next, I have this to answer, that (though I did not tell the
_Reader_ so much, to the end that he might have the more freedom to examine
and judg of the contrivance, yet) it was not meer _Theory_ I propounded,
but somewhat of _History_ and _matter of Fact_: For, I had made trials, as
many as my leisure would permit, not without some good success; but not
having time and opportunity enough to prosecute them, I thought it would
not be unacceptable to such, as enjoyed both, to have a description of a
way altogether _New_, and _Geometrically_ true, and seemingly, not
unpracticable, whereof they might make use, or not, as they should see
reason. But nothing surprised me so much, as, that he is pleased (after he
had declared it a fault, to write this _Theory_, without having reduced it
to practice) to lay it, as he seems to do, in one place of his book, _p._
22 upon the _Royal Society_. Truly, _Sir_, I should think my self most
injurious to that _Noble Company_, had I not endeavoured, even in the
beginning of my Book, to prevent such a misconstruction. And therefore I
cannot but make this interpretation of what Monsieur _Auzout_ saith in this
particular, that either he had not so {65} much of the Language wherein I
have written, as to understand all what was said by me, or, that he had not
read my _Dedication_ to the _Royal Society_, which if he had done, he would
have found, how careful I was, that that _Illustrious Society_ should not
be prejudiced by my _Errors_, that could be so little advantaged by my
_Actions_. And indeed, for any man to look upon the matters published by
their Order or Licence, as if they were _Their_ Sense, and had _Their_
Approbation, as _certain_ and _true_, 'tis extremely wide of their
intentions, seeing they, in giving way to, or encouraging such
publications, aim chiefly at this, that _ingenious conceptions_, and
important _philosophical matter of Fact_ may be communicated to the learned
and enquiring World, thereby to excite the minds of men to the examination
and improvement thereof. But, to return; As to his _Objections_ against the
_Matter_, I do find that they are no more against mine, than any other way
of _Grinding Glasses_; nor is it more than I have taken notice of my self
in this Passage of the same _Paragraph_, of which sort are also those
difficulties he raises about _Long Glasses_, which are commonly known to
such, as are conversant in making them _It would be convenient also_ (these
are my words) _and not very chargeable, to have four or five several Tools:
One,_ &c. _And, if curiosity shall ever proceed so farr, one for all
lengths, between 1000. and 10000. foot long; for indeed, the _Principle_ is
such, that supposing _the Mandrils well_ made, and of a good length, and
supposing _great care_ be used in working and polishing them, I see no
reason, but that a Glass of 1000. nay, 10000. foot long may be made, as
well as one of 10. For, the reason is the same, supposing the _Mandrils_
and _Tools_ be made sufficiently strong, so that they cannot bend; and
supposing also that the Glass out of which they are wrought, be capable of
so great a regularity in its parts, as to its Refraction._ But next, I must
say that his _Objections_ to me, seem not so considerable, as perhaps he
imagines them. For, as to the possibility of getting Plates of Glass thick
and broad enough without veins, I think _that_ not now so difficult here in
_England_, where I believe is made as good, if not much better Glass for
_Optical Experiments_, than ever I saw come from _Venice_. Next, though it
were better, that the thickest part of a long _Object-Glass_ were exactly
in the middle, yet I can assure Monsieur _Auzout_, that it may be a very
{66} good one, when it is an Inch or two out of it. And I have a good one
by me at present, of 36. foot, that will bare an _Aperture_, if _Saturn_ or
the _Moon_ in the _twilight_, be look'd on with it, of 3½ Inches over, and
yet the thickest part of the Glass is a great way out of the middle. And I
must take the liberty to doubt, whether ever my _Animadversor_ saw a long
Glass, that was otherwise; as he might presently satisfie himself by a way
I could shew him (if he did not know it) whereby the difference of the
thickness of the sides might be found to the hundreth part of a Line.

As to the exceeding exactness of the _Figure_ of Long _Object-Glasses_,
'tis not doubted, but that it is a matter difficult enough to be attained
any way: but yet, I think, much easier by _Engine_, than by _Hand_; and of
all _Engines_, I conceive, none more plain and simple, than that of a
_Mandril_. And for making _spherical Glasses_ by an _Engine_, I am apt to
think, there hardly can be any way more plain, and more exact, than that
which I have described; wherein there is no other motion, than that of two
such _Mandrils_, which may be made of sufficient strength, length, and
exactness, to perform abundantly much more, than I can believe possible to
be done otherwise than by chance, by a man's hands or strength unassisted
by an _Engine_, the motion and strength being much more certain and
regular. I know very well, that in making a 60. foot Glass by the strength
of the hand, in the common way, not one of ten that are wrought, will
happen to be good, as I have been assured by Mr. _Reeves_; who, I am apt to
think, was the first that made any good of that length. For the _Figure_ of
the _Tool_ in that way is presently vitiated by the working of the Glass,
and without much _gaging_ will not do any thing considerable. Besides, the
strength of a man's hands, applied to it for the working and polishing of
it, is very unequal, and the motions made, are very irregular; but in the
way, I have ventured to propose, by _Mandrils_, the longer the _Glass_ and
_Tool_ are wrought together, the more exact they seem to be and if all
things be ordered, as they should be, the very polishing of the Glass, does
seem most of all rectifie the _Figure_.

As to what he objects, that the Tool does only touch the Glass in a
_Mathematical Circle_; that is true, perhaps, at first, but before the
Glass is wrought down to its true _Figure_, the _Edge_ of the _Tool_ {67}
will be worn or grownd away, so as that a Ring of an inch broad may be made
to touch the _Spherical Surface_ of the Glass; nay, if it be necessary
(without much trouble, especially in the grinding of longer Glasses) the
whole _Concave Surface_ of the _Tool_ may be made to touch a Glass.
Besides, that as to the keeping a quantity of the same sand and Powders of
several finesses, according as the glass wears, the same is possible to be
don, as with the same Sand wrought finer by working in the Ordinary way.

The giving the _Inclination_ to the _Mandrils_, is not at all difficult;
though perhaps to determine the length exactly which the Glass so made
shall draw, is not so easie: But 'tis no matter, what length the Glass be
off, so it be made good, whether 60 or 80 foot, or the like. Nor is it so
very difficult, to lay them both in the same _Plain_. And to keep them
_steddy_, when once fix'd, is most easie.

As to the Calculation of the propriety of a Glass of a thousand foot,
perhaps for that particular Length, I had not, nor have as yet calculated,
that the Convexity of one of eighteen inches broad, will not be above a
seventh part of a Line. But it does not thence follow, that I had not
considered the difficulties, that would be in making of it. For, I must
tell him, that I can make a _Plano convex_ Glass though its convexity be a
smaler sphere than is usual for such a length to be an _Object-Glass_ of
about 150 foot in Length, nay of 300 foot, and either longer or shorter,
_without_ at all _altering the convexity_. So that, if he will by any
Contrivance he hath, give me a _Plano-convex_ Glass of 20, or 40 foot
_Diameter_, without _Veins_, and truly wrought of that _Figure_, I will
presently make a _Telescope_ with it, that with a single Ey-glass shall
draw a thousand foot: Which _Invention_, I shall shortly discover, there
being, I think, nothing more easie and certain. And if a _Plano-convex_
Glass can be made of any _Sphere_ between twenty and fourty foot _radius_,
so as that both the _Convex_ and _Plain_ side of the Glass be exactly
polish'd of a true _Figure_, I will shortly shew, how therewith may be made
a _Telescope_ of any Length, supposing the Glass free from all kind of
_Veins_, or inequality of _Refraction_.

As for the sliding of the Glass upon the _Cement_, I see no reason at all
for it, at least in the _Cement_, I make use of, having never observed any
such accident in hard _Cement_. {68}

And for the Bearing of the _Ring_ against one side of the Glass only at a
time, I cannot see, why _that_ should produce any inequality, since all the
sides of the Glass have successively the same pressure.

His ratiocination concerning a Glass of 300 foot, is much the same with the
former, about the difficulty of working a true surface of a convenient
figure; which how considerable both _that_ and his Conclusion thereupon
(_videl. That we are not to expect Glasses of above 300 or 400 foot long at
most, and that neither _Matter_ nor _Art_ will go so far_) is, may be
judged from what I have newly told you of making any _Object-Glass_ of any
Length.

And for his good wishes, that those, who promise to make him see _Plants_
or _Animals_ in the _Moon_ (of which I know not any, that has done so,
though perhaps there may be some, notwithstanding his Objections, that do
not yet think it impossible to be done) had considered, what a Man is able
to see with his _bare_ Eye at 60 Leagues distance: I cannot but return him
my wishes, that he would consider the difference between seeing a thing
through the _Gross_ and _Vaporous_ Air neer the Earth, and through the Air
over our heads: Which, if he observe the Moon in the _Horizon_, and neer
the _Zenith_ with a _Telescope_, he will experimentally find; and, having
done so, he will perhaps not be so dissident in this matter.

Concerning his Advertisement to such, as publish _Theories_, I find not,
that he hath made use of it in his own case. For, in his _Theory_ about
_Apertures_ he seems to be very positive, not at all doubting to rely upon
it, _vid._ that the _Apertures_ must be _thus_ and _thus_ in _great_
Glasses, because he had found them _so_ or _so_ in some _small_ ones.

For his Proposal of amendments of some inconveniencies in this way, I
return him my thanks; but as to his first I believe, that the matter may be
conteined as wel in the _Concave_ Tool, as on the _convex_ Glass. And as to
that of 2 _Poppet-heads_ I do not well understand it, if differing from
mine; and the keeping of the Tool upon the Glass with a spring or weight,
must quickly spoyl the whole; since, if either of the _Mandrils_ will
easily yield backwards, the _regularity_ of _all_ will be spoiled: and as
to the wrigling and playing of the _Mandril_, I do not at all apprehend it.
{69}

His _Theory_ of _Apertures_, though he seems to think it very authentick,
yet to me it seems not so cleer. For, the same Glass will endure greater or
lesser _Apertures_, according to the lesser or greater Light of the
_Object_: If it be for the looking on the _Sun_ or _Venus_, or for seeing
the _Diameters_ of the _Fix'd Stars_, then smaller _Apertures_ do better;
if for the _Moon_ in the _daylight_, or on _Saturn_, or _Jupiter_, or
_Mars_, then the largest. Thus I have often made use of a 12 foot-Glass to
look on _Saturn_ with an _Aperture_ of almost 3 inches, and with a single
Eye-glass of 2 inches _double convex_: but, when with the same Glass I
looked on the _Sun_ or _Venus_, I used both a smaller _Aperture_, and
shallower _Charge_. And though M. _Auzout_ seems to find fault with the
_English_ Glass of 36 foot, that had an _Aperture_ of but 2¾ inches
_French_; as also, with a 60 foot _Tube_, used but with an _Aperture_ of 3
inches; yet I do not find, that he hath seen Glasses of that length, that
would bear greater _Apertures_, and 'tis not impossible, but his _Theory_
of _Apertures_ may fail in longer Glasses.

       *       *       *       *       *

_Of a means to illuminate an Object in what proportion one pleaseth; and of
the Distances requisite to burn Bodies by the _Sun_._

One of the means used by M. _Auzout_ to enlighten an Object, in what
proportion one pleaseth, is by some great _Object-Glass_, by him called a
_Planetary_ one, because that by it he shews the difference of Light, which
all the _Planets_ receive from the _Sun_, by making use of several
_Apertures_, proportionate to their distance from the _Sun_, provided that
for every 9 foot draught, or thereabout, one inch of _Aperture_ be given
for the _Earth_. Doing this, one sees (_saith he_) that the Light which
_Mercury_ receives, is far enough from being able to burn Bodies, and yet
that the same Light is great enough in _Saturn_ to see cleer there, seeing
that (to him) it appears greater in _Saturn_, than it doth upon our
_Earth_, when it is overcast with Clouds: Which (he adds) would scarce be
believed, if by means of this Glass it did not sensibly appear so; Whereof
he promises to discourse more fully in his {70} _Treatise of the usefulness
of great Optick-Glasses_, where he also intends to deliver several
Experiments, by him made, 1. Touching the quantity of Light, which a Body,
that is 10, 15 and 20 times, &c. remoter than _Saturn_, would yet receive
from the _Sun_. 2. Touching the quantity of Light, by which the _Earth_ is
illuminated even in the _Eclipses_ of the _Sun_, in proportion of their
bigness. 3. Touching the quantity of Light, which is necessary to burn
Bodies: he having found, that not abating the Light, which is reflected by
the Surfaces of the Glass (whereof he confesseth, he doth not yet exactly
know the quantity) there would be necessary about 50 times as much Light,
as we have here, for the burning of _Black_ Bodies; and neer 9 times more
for the burning of _White_ Bodies, than for the burning of _Black_ ones:
and so observing the immediate proportions between these two, for burning
bodies of _other_ Colors. Whence (he tells us) he hath drawn some
consequences, touching the distance, at which we may hope, to burn Bodies
here, by the means of _great Glasses_ and great _Looking-glasses_. So that
(_saith he_) we must yet be seven times neerer the _Sun_, than we are, to
be in danger of being burned by it. Where he mentions, that having given
_Instructions_ to certain persons, gon to travel in _Hot Countries_, he
hath among other particulars recommended to them, to try by means of great
_Burning-glasses_, with how much less _Aperture_ they will burn _there_,
than _here_, to know from thence, whether there by more Light _there_ than
_here_, and how much; since this perhaps may be the only means of trying
it, supposing, the same matters be used: although the difference of the Air
already heated, both in _hot Countries_, and in the _Planets_, that are
neerer than we, may alter, if not the quantity of Light, at least that of
the Heat, found there.

       *       *       *       *       *

_A further Account, touching Signor _Campani_'s Book and Performances about
_Optick-glasses_._

In the above-mentioned _French_ Tract there is also conteined M. _Auzout's_
Opinion of what he had found New in the _Treatise_ of Signor _Campani_,
which was spoken of in the first _Papers_ of these _Transactions_,
concerning both the Effect of the _Telescopes_, contrived after a peculiar
way by the said _Campani_ at _Rome_, and {71} his New Observations of
_Saturn_ and _Jupiter_, made by means thereof.

First therefore, after that M _Auzout_ had raised some scruple against the
Contrivance of Signor _Campani_ for making _Great Optick-Glasses_ without
_Moulds_, by the means of a _Turn-lath_, he examines the _Observations_,
made with such _Glasses_: Where, having commended _Campani_'s sincerity in
relating what he thought to have seen in _Saturn_, without accomodating it
to M. _Hugens_'s _Hypothesis_, he affirms, that supposing, there be a
_Ring_ about _Saturn_, Signor _Campani_ could not see in all those
different times, that he observed it, _the same Appearances_, which he
notes to have _actually_ seen. For, having seen it sometimes in _Trine
Aspect_ with the _Sun_, and _Oriental_; sometimes, in the same _Aspect_,
but _Occidental_; sometimes in _Sextil Aspect_, and _Occidental_; at
another time, again in _Trine_, and _Oriental_, this Author cannot
conceive, how _Saturn_ could in all these different times have no
difference in its _Phasis_, or keep always the same _Shadow_; seeing that,
according to the _Hypothesis_ of the _Ring_, when it was _Oriental_, it
must cast the _Shadow_ upon the _left_ side of the _Ring_ beneath, without
casting any on the _right_ side: and when it was _Occidental_, it could not
but cast it on the _right_ side beneath, and nothing of it on the other.

Concerning the _Shadow above_, which _Campani_ affirms to be made by the
_Ring_ upon the Body of _Saturn_, M. _Auzout_ judges, that there could be
no such _Phænomenon_, by reason of its _Northern Latitude_ at the times,
wherein the _Observations_ were made, _vid._ in _April_ 1663; in the midst
of _August_, and the beginning of _October_, next following, and in _April_
1664, except it were in _October_, and the _Shadow_ strong enough to become
_visible_.

But as to the _Shadow below_, he agrees with _Campani_, that it does
appear, yet not as he notes it, seeing that it must be sometimes on the one
side, sometimes on the other; and towards the _Quadrat_ with the _Sun_ it
must appear biggest, as _indeed_ he affirms to have seen it himself _this_
year, insomuch that sometimes it seemed to him, that it covered the whole
_Ring_, and that the _Shadow_, joyning with the obscure space between both,
did interrupt the circumference of the _Ring_; but beholding it at other
times in a cleer Sky, and when there was no Trepidation of the Air, {72} he
thought, that he saw also the Light continued from without, although very
slender. But he acknowledges, that he could never yet _precisely_
determine, by how much the largeness of the _Ring_ was bigger than the
_Diameter_ of _Saturn's_ Body. As for the proportion of the Length to the
Breadth, he affirms, to have alwaies estimated it to be two and a half, or
very neer so; and to have found in his _Observations_, that in _January_
last, one time, the length of _Saturn_ was 12 _Lines_, and the breadth 5.
Another time, the length was 12. _Lines_, and the breadth 4. and this by a
peculiar method of his own. But yet he acknowleges also, that sometimes he
hath estimated it as 7. to 3. and at other times as 13. to 5. and that if
there do not happen a change in the magnitude of the _Ring_ (as it is not
likely there does) that must needs proceed from the Constitution of the
air, or of the Glass's having more or less _Aperture_, or from the
difficulty of making an exact estimate of their proportions. However it is
not much wide (saith he) of two and a half, although _Campani_ make the
length of the _Ring_ but double to its breadth.

Monsieur _Auzout_ believes, that he was one of the first that have well
observed this shadow of _Saturn's_ Body upon its _Rings_ which he affirms
happened two years since; when, observing in _July_, for the first time,
with a _Telescope_ of 21. and then another of 27. foot, he perceived, that
the _Angle_ of the obscure space on the _right side_ beneath, was bigger
and wider, than the three other _Angles_, and that some interruption
appear'd _there_, between the _Ring_, and the _Body of Saturn_; of which he
saith to have given notice from that time to all his friends, and in
particular, as soon as conveniently he could, to Monsieur _Hugens_.

He confesseth, that he hath not had the opportunity of observing _Saturn_
in his _Oriental Quadrat_; yet he doubts not, but that the _shadow_ appears
on the _Left-side_, considering, that the _Existence_ of the _Ring_ can be
no longer doubted of, after so many _Observations_ of the _shadow_ cast by
_Saturn's_ Body upon it, according as it must happen, following that
_Hypothesis_; there being no reason, why it should cast the said _shadow_
on one side, and not on the other.

Concerning the Observation of _Jupiter_ and its _satellites_, the famous
_Astronomer_ of _Bononia_, _Cassinus_, having {73} published, that on the
30. day of _July_, 1664. at 2½ of the clock in the morning, he had
observ'd, with _Campani_'s Glasses, that there passed through the broad
obscure _Belt_ of _Jupiter_ two obscurer _spots_, by him esteemed to be the
_shadows_ of the _Satellites_, moving between _Jupiter_ & the _Sun_, and
eclipsing him, and emerging from the Occidental Brim thereof: This
_Authour_ did first conceive, that they were not _shadows_, but some
_Sallies_, or _Prominencies_ in that _Belt_; which he was induced to
believe, because he perceived not, that that _Prominency_, which he there
saw, was so black, nor so round as _Cassini_ had represented his _spots_;
wherefore, seeing it but little differing in colour, from the _Belt_, and
so not judging it round, because it did stand only about half its diameter
out of the _Belt_, he persuaded himself, that it was rather a _Sally_, or
_Prominency_ of the _Belt_, than a round _shadow_, as that of a _Satellite_
of _Jupiter_ must have bin. But having been since informed of _all_ the
_Observations_ made by _Cassini_ and _Campani_, with the _New_ Glasses, and
seen his _Figure_, he candidly and publickly wisheth, that he had not
spoken of that _Sally_, or _Prominency_; advowing that he can doubt no
longer, but that it was the _shadow_ of the _Satellit_ between _Jupiter_
and the _Sun_, having seen the other emerge, as soon as with a 20. foot
Glass he made the Observation, and having not perceiv'd these _shadows_
with a 12. foot Glass: But although he grants that they did ghess better
than he, yet he doth it with this _proviso_, _vid._ in case they made
_that_ Observation on of _July_ 30. not with their 36. but 12. or 17. foot
_Telescope_. If it be wondred at, that Monsieur _Auzout_ did not see this
_shadow_ move, he allegeth his indisposition for making _long
Observations_, and addeth, that it may be much more wondred at, that
neither _Campani_ nor himself did see upon the obscure _Belt_ the Bodies of
the _Satellites_, as parts more Luminous than the _Belt_. For (saith he)
although the _Latitude_ was _Meridional_, it being no more than of 9. or
10. minutes, the Body of the _Satellites_ should, thinks he, pass between
_us_ and the _Belt_, especially according to _Campani_, who maketh the
_Belt_ so large, and puts the _shadows_ farr enough within the same. This
maketh him conclude, that either they have not observed well enough, or
that the motion of the _Satellites_ doth not exactly follow the _Belts_,
and is inclin'd unto them. Whereupon he resolves, that when he shall know
that they are to pass between _Jupiter_ and _us_, and to be over against
the _Belt_, that {74} then he will observe, whether he can see them appear
upon the _Belt_, as upon a darker ground, especially, the _third_ of them,
which is sensibly greater, and more Luminous, than the rest. He hopeth
also, that in time, the _shadow_ of _Saturns Moon_ will be seen upon
_Saturn_, although we are yet some years to stay for it, and to prepare
also for better Glasses.

From this rare Observation, he inferrs the _Proportion_ of the _Diameter_
of the _Satellites_ to that of _Jupiter_; and judgeth, that no longer doubt
can be made of the turning of these 4. _Satellites_, or _Moons_ about
_Jupiter_, as our _Moon_ turns about the _Earth_, and after the same way as
the rest of the Celestial Bodies of our _Systeme_ do move: whence also a
strong conjecture may be made, that _Saturns_ Moon turns likewise about
_Saturn_.

Hence he also taketh occasion to intimate, that we need not scruple to
conclude, that if these two _Planets_ have _Moons_ wheeling about them, as
our _Earth_ hath one that moves about it, the conformity of these _Moons_
with our _Moon_, does prove the conformity of our _Earth_ with those
_Planets_, which carrying away their _Moons_ with themselves, do turn about
the _Sun_, and very probably make their _Moons_ turn about them in turning
themselves about their _Axis_; and also, that there is no cause to invent
perplex'd and incredible _Hypotheses_, for the receding from this
_Analogie_ since (saith he) if this be truth, the Prohibitions of
publishing this doctrine, which formerly were caused by the offence of
Novelty, will be laid aside, as one of the most zealous Doctors of the
contrary Opinion hath given cause to hope, witness _Eustachius de Divinis_,
in his _Tract_ against Monsieur _Hugen_'s _Systeme_ of _Saturn_, _p._ 49.
where we are inform'd, that that learned Jesuit, _P. Fabry_, Penitentiary
of S _Peter_ in _Rome_, speaks to this purpose:

Ex vestris, iisque Coryphæis non semel quæsitum est, utrum aliquam haberent
demonstrationem pro _Terræ motu_ adstruendo. Nunquam ausi sunt id asserere
Nul igitur obstat quin loca illa in sensu literali Ecclesia intelligat, &
intelligenda esse declaret, quamdiu nulla demonstratione contrarium
evincitur; quæ si forte aliquando a vobis excogitetur (quod vix crediderim)
in hoc casu nullo modo dubitabit Ecclesia declarare, loca illa in sensu
figurato & improprio intelligenda esse, ut illud Poetæ, _Terræque Urbesque
recedunt_.

_It hath been more than once asked of your Chieftains, whether they had a
Demonstration for asserting the motion of the Earth? They durst never yet
affirm they had; wherefore nothing hinders, but that the Church may
understand those Scripture-places, that speak of this matter, in a
_literal_ sence, and declare they should be so understood, as long as the
contrary is not evinced by any demonstration; {75} which, if perhaps it
should be found out by you (which I can hardly believe it wil) in this case
the Church will not at all scruple to declare, that these places are to be
understood in a figurative and improper sence, according to that of the
Poet, _Terræque Urbesque recedunt_._

Whence this Author concludes, that the said _Jesuite_ assuring us that the
_inquisition_ hath not _absolutely_ declared, that those Scripture-places
are to be understood _literally_, seeing that the _Church_ may make a
contrary declaration, no man ought to scruple to follow the _Hypothesis_ of
the _Earths motion_, but only forbear to maintain it in _publick_, till the
prohibition be called in. But to return to the matter in hand, this Author,
upon all these observations and relations of _Cassini_ and _Campani_, doth
find no reason to doubt any more of the excellency of the Glass used by
them, above his; except this difference may be imputed to that of the
_Air_, or of the _Eys_. But yet he is rather inclined to ascribe it to the
goodness of their Glasses, and that the rather, because, he would not be
thought to have the vanity of magnifying his own; of which, yet he
intimates by the by, that he caused one to be wrought, of 150 _Parisian_
feet; which though it proved none of the best, yet he despairs not to make
good ones of _that_, and of far greater Length.

       *       *       *       *       *

__Signor Campani's_ Answer: and Monsieur _Auzout_'s Animadversions
thereon._

The other part of this _French Tract_, conteining _Campani_'s Answer, and
Mr. _Auzout_ his _Reflections_ thereon, begins with the pretended _Shadows_
of the _Ring_ upon _Saturn_, and of _Saturn_ upon the _Ring_. Concerning
which, the said _Campani_ declareth, that he never believed them to be
_shadows_, made by the _Ring_ upon the _Disk_ of _Saturn_, or by the body
of _Saturn_ upon the _Ring_, but the _Rimms_ of these bodies, which being
_unequally_ Luminous, did shew these appearances. In which Explication,
forasmuch as it represents, that the said _Campani_ meant to note only the
_Inequality of the Light_, which, _he saith_, his Glasses did discover, Mr.
_Auzout_ does {76} so far acquiesce, that he only wishes, that his own
Glasses would shew him those differences. Next to the Objection, made by
Monsieur _Auzout_, against Signor _Campani_, touching the Proportion of the
Length of the _Ring_ to its breadth, _Campani_ replyeth, that the Glasses
of Monsieur _Auzout_, shew not all the particulars, that his do, and
therefore are unfit for determining the true Figure and breadth of the
apparent _Ellipsis_ of the _Ring_. To which M. _Auzout_ rejoyns, that he is
displeased at his being destitute of better Glasses, but that it will be
very hard for the future to convince _Campani_ touching the _Proportion_ of
the _Ring_, seing that the breadth of the _Ellipsis_ is always diminishing,
although, if the declination of the _Ring_ remains always the same, one can
at all times know, which may have been its greatest breadth. But he
assures, that the breadth of the _Ring_ is not the half of its length, and
that it doth not spread out so much beyond _Saturn_'s Body, as he hath
alleged. And withal desirs to know, what can be answered by Sig. _Campani_
to M. _Hugens_, who being persuaded, that the Declination of the _Ring_ is
not above 23 deg. 30' having seen the _Ring_ to spread out above the Body
of _Saturn_, concludes, in a Letter to M. _Auzout_, that the length of the
_Ring_ is more than treble the _Diameter_ of _Saturn_'s body, which,
according to _Campani_, is only as about 67 to 31. Which difference yet dos
not appear to M. _Auzout_ to be so great; but that M. _Hugens_ perhaps will
impute it to the Optical reason, which he (_Auzout_) hath alleged of the
Advance of the light upon the obscure space; although he is of Opinion, he
should not have concluded so great a Length, if he had not seen the Breadth
spread out more, than he hath done: for (_saith he_) if the Length of the
_Ring_ be to the body of _Saturn_, 2½ to 1. and the _Inclination_ be 23
deg. 30' the _Ring_ will be just as large, as the body, without spreading
out; but if the _Ring_ be bigger, it will a little spread out; and if it
were treble, it must needs spread out the half of its breadth, which hath
not so appeared to him.

Further, to M. _Auzout's_ change of Opinion, and believing, that the
_Advance_ or _Sally_, seen by him in _Jupiter_, was the _Shadow_ of one of
his Moons, _Campani_ declares, that he would not have him guilty of that
change: Whereupon M. _Auzout_ wonders, why _Campani_ then hath not marked
it in his _Figure_; and would {77} gladly know, whether that _Sally_ be
more easie to discover, than the _Shadows_ of the _Satellites_, which
_Campani_ believs, _Auzout_ hath not seen; and whether he be assured, that
those obscure parts, which he there distinguishes, do not change: for if
they should not change, then _Jupiter_ would not turn about his _Axis_,
which yet, he saith, it doth, according to the _Observation_ made by Mr.
_Hook_, _May_ 9 1664. inserted in the first papers of these _Transactions_.
The full Discovery of which particular also he makes to be a part of
_Cassini's_ and _Campani_'s work, seeing that they so distinctly see the
inequalities in the _Belts_, and see also sometimes other _Spots_ besides
the _Shadows_ of the _Satellites_: where he exhorts all the Curious, that
have the conveniency of observing, to endeavor the discovery of a matter of
that importance, which would prove one of the greatest _Analogies_ for the
_Earth's Motion_.

       *       *       *       *       *

_An Account of Mr. _Richard Lower_'s newly published _Vindication_ of
Doctor _Willis_'s _Diatriba_ de _Febribus_._

The Title of this Curious piece, is _Diatribæ Thomæ Willisii Med. Doct. &
Profess. Oxon. De Febribus Vindicatio, Authore Richardo Lower, &c._ In it
are occasionally discussed many considerable Medical and Anatomical
inquiries, as, Whether a Fever does consist in an Effervescence of Blood?
And if so, of what kind? Whether there be a _Nervous_ and _Nutritious_
Juice? Whether the office of sanguification belongs to the Blood it self,
existing _before_ those _Viscera_ (at least) that are commonly esteemed to
be the Organs of sanguification? How _Nutrition_ is performed, and the
nourishing substance assimilated? Whether the Blood affords both the Matter
for the structure of the Body, and such parts also, as are fit for the
nourishment of the same? Whether the Pulse of the Heart ceasing, there
remains yet a certain Motion in the blood, arguing, that _Pulse_ and _Life_
do ultimately rest in the _Blood_? Whether the Umbilical Vessels convey the
blood of the Mother to the Child, or whether the _Foetus_ be for the most
part form'd and {78} acted by the circulating blood, before the existence
of the Umbilical Vessels, or before the connecting of the _Foetus_ with the
_Uterus_? A new Experiment to prove that the _Chyle_ is not transmuted into
_Blood_ by the _Liver_. A discourse of the Nature of the _Blood_, and what
difference there is between the _Venal_ and _Arterial_ blood, and for what
Uses both the one and the other are particularly designed. Where it is
considered, what _Life_ is, and whence the _Soul_ of _Brutes_, and its
subsistence, and operations do depend. It is also inquired into, what the
uses of the _Lungs_ are in _hot_ Animals? And many other such material
disquisitions are to be found in this small, but very Ingenious and Learned
Treatise.

       *       *       *       *       *

_A Note touching a Relation, inserted in the last _Transactions_._

In the Experiment of killing _Ratle-Snakes_, mentioned in the last of the
precedent Papers (wherein, by a mistake, these words, _The way_, were put
for _A way_, or _An Experiment_) it should have been added, that the
Gentleman there mention'd, did affirm, that, in those places, where the
Wild _Penny-Royal_ or _Dittany_ grows, no _Ratle-Snakes_ are observed to
come.

       *       *       *       *       *


_Errata._

Pag. 59. line 11. read, _bignesses_, l. 20. r. _endure_, for, resist. l.
30. r. _those_, for, these. l. 31. r. _Plain_, for, place.

       *       *       *       *       *


_LONDON,_

Printed with Licence, By _John Martyn_, and _James Allestry_, Printers to
the _Royal-Society_, at the _Bell_ in St. _Pauls Church-Yard_. 1665.

{79}

       *       *       *       *       *




_Numb._ 5.

PHILOSOPHICAL
_TRANSACTIONS._

       *       *       *       *       *

_Munday_, _July_ 3. 1665.

       *       *       *       *       *

The Contents.

    _An Account, how _Adits_ and _Mines_ are wrought at _Liege_ without
    _Air-shafts_, communicated by Sir _Robert Moray_. A way to break
    _easily_ and _speedily_ the hardest _Rocks_; imparted by the same
    _Person_, as he received it from Monsieur _Du Son_ the Inventor.
    Observables upon a _Monstrous Head_. Observables in the Body of the
    Earl of _Belcarres_, sent out of _Scotland_. A Relation of the designed
    Progress to be made in the _Breeding of Silk-worms_, and the _Making_
    of _Silk_, in _France_. Enquiries touching _Agriculture_, for _Arable_
    and _Meadows_._

       *       *       *       *       *

_An Account, how _Adits_ & _Mines_ are wrought at _Liege_ without
_Air-shafts_, communicated by Sir _Robert Moray_._

It is well known to those conversant in _Mines_, that there is nothing of
greater inconvenience in the working or _driving_, as they call it, of
_Mines_ or _Adits_ under ground, for carrying away of Water, or such
_Minerals_ as the _Mine_ affords, than the _Damp, want,_ and _impurity of
Air,_ that {80} occur, when such _Adits_ are wrought or driven inward upon
a _Level_, or near it, 20, 30, or 40. fathom, more or less. Aswel because
of the expence of money, as of time also, in the _Ordinary_ way of
preventing or remedying those inconveniences; which is, by letting down
_shafts_ from the _day_ (as _Miners_ speak) to meet with the _Adit_; by
which means the Air hath liberty to play through the whole work, and so
takes away bad vapours and furnishes good Air for Respiration. The Expence
of which _shafts_, in regard of their vast depth, hardness of the Rock,
drawing of water, &c. doth sometimes equal, yea exceed the _ordinary_
charge of the whole _Adit_.

Amongst the _Expedients_ that have been devised to remedy this, there is
one practised in the _Coal-mines_, near the Town of _Liege_ (or _Luyck_)
that seems preferable to all others for Efficacy, Ease, and Cheapness: the
description whereof followeth.

At the mouth or entry of the _Adit_ there is a structure raised of _Brick_,
like a _Chimney_, some 28. or 30. foot high in all: at the bottom, two
opposite sides are (or may be) some 5½ foot broad; and the other two, 5.
foot: the wall 1½ _Brick_ thick. At the lower part of it, is a hole, some
9. or 10. inches square, for taking out of the Ashes, which when it is
done, this Ash-hole is immediately stopt so close, as Air cannot possibly
get in at any part of it. Then, some 3. foot above ground or more, there is
on that side, that is next to the _Adit_ or Pit, a square hole of 8. or 9.
inches every way, by which the Air enters to make the Fire burn: Into this
hole there is fixed a square _Tube_ or _Pipe_ of Wood, whereof the Joints
and Chinks are so stopt with Parchment pasted or glewed upon them, that the
Air can no where get in to the Pipe but at the end: And this Pipe is still
lengthened, as the _Adit_ or Pit advanceth, by fitting the new Pipes so, as
one end is alwaies thrust into the other, and the Joints and Chinks still
carefully cemented and stopt as before. So the Pipe or Tube being still
carried on, as near as is necessary, to the wall or place, where fresh Air
is requisite; the Fire within the Chimney doth still attract {81} (so to
speak) Air through the Tube, without which it cannot burn, which yet it
will do, as is obvious to conceive (all Illustrations and Philosophical
Explications being here superfluous,) and so, while the Air is drawn by the
fire from the farthest or most inward part of the _Mine_ or _Adit_, fresh
Air must needs come in from without to supply the place of the other, which
by its motion doth carry away with it all the ill vapors, that breath out
of the ground; by which meanes the whole _Adit_ will be alwaies filled with
fresh Air, so that men will there breath as surely as abroad, and not only
Candles burn, but Fire, when upon occasion there is use for it for breaking
of the Rock.

Now that there may be no want of such fresh Air, the Fire must alwaies be
kept burning in the Chimney, or at least as frequently as is necessary: For
which purpose there must be two of the Iron Grates or Chimneys, that when
any accident befals the one, the other may be ready to be in its place, the
Coals being first well kindled in it: but when the fire is neer spent, the
Chimney or Grate being haled up to the dore, is to be supplied with fresh
fuel.

The Figure of the Fabrick, Chimney, and all the parts thereof being
hereunto annexed, the rest will be easily understood.

[Illustration]

_Figure_ 1.

A. The _Hole_ for taking out the Ashes.

B. The _Square-hole_, into which the Tube or Pipe for conveying the Air is
to be fixed.

C. The _Border_ or _Ledge_ of _Brick_ or _Iron_, upon which the
_Iron-grate_ or _Cradle_, that holds the burning Coals, is to rest, the one
being exactly fitted for the other.

D. The _Hole_ where the _Cradle_ is set.

E. The woodden _Tube_, through which the Air is conveyed towards the
_Cradle_.

F. The _Dore_, by which the _Grate_ and _Cradle_ is let in, which is {82}
to be set 8. or 10. foot higher than the Hole D. and the _Shutter_ made of
Iron, or Wood that will not shrink, that it may shut very close, this
_Dore_ being made large enough to receive the _Cradle_ with ease.

G. The _Grate_ or _Cradle_, which is narrower below than above, that the
Ashes may the more easily fall, and the Air excite the Fire; the bottom
being barred as the sides.

H. The _Border_ or _Ledge_ of the _Cradle_, that rests upon the _Ledge_ C.

I. Four _Chains_ of _Iron_ fastned to the four corners of the _Cradle_, for
taking of it up, and letting of it down.

K. The _Chain_ of _Iron_, to which the other are fastned.

L. The _Pulley_ of _Iron_ or _Brass_, through which the _Chain_ passeth.

M. A _Hook_, on which the end of the _Chain_ is fastned by a _Ring_, the
_Hook_ fixed being placed in the side of the Dore.

N. A _Barr_ of _Iron_ in the Walls, to which the _Pulley_ is fastned.

The higher the _Shaft_ of the Chimney is, the Fire draws the Air the
better. And this Invention may be made use of in the _Pits_ or _Shafts_,
that are _Perpendicular_, or any wise inclining towards it, when there is
want of fresh Air at the bottom thereof, or any molestation by unwholsom
Fumes or Vapors:

       *       *       *       *       *

_A way to break _easily_ and _speedily_ the hardest _Rocks_, communicated
by the same Person, as he received it from Monsieur _Du Son_, the
Inventor._

[Illustration]

Though the invention of breaking with ease, and dispatch, hard Rocks, may
be useful on several occasions, the benefit is incomparably great, that may
thereby accrue to those, who have _Adits_ or Passages to cut through hard
_Rocks_, for making passage for Water to run out by, in _Mines_ of _Lead_,
_Tin_, or any other whatsoever; these _Adits_ appearing to be the surest,
cheapest, and most advantagious way imaginable, for draining of the same.
{83}

That which is here to be described, was invented by one of the most
Excellent _Mechanicks_ in the World, _Monsieur du Son_, who lately put it
in practice himself in _Germany_, at the desire of the _Elector_ of
_Mentz_. The manner is, as followeth.

The _Mine_ or _Adit_ is to be made seven or eight foot high, which though
it seem to make more work downwards, yet will be found necessary for making
the better dispatch by rendring the Invention more effectual.

There is a _Tool_ or _Iron_ well steeled at the end, which cuts the Rock,
(of the shape shewed by _Fig._ 2. here annexed,) 20. or 22. Inches long or
more, and some 2½ Inches _Diameter_ at the steeled end, the rest being
somewhat more slender. The steeled end is so shaped, as makes it most apt
to pierce the Rock, the Angles at that end being still to be made the more
obtuse, the harder the Rock is. This _Tool_ is to be first held by the
hand, in the place, where the Hole, to be made for the use, which shall
here be shewed, is to be placed; that is, in the middle between the sides
of the Rock, that is to be cut, but as near the bottom as may be. The
_Tool_ being placed, is to be struck upon with an Hammer, the heavier the
better, either suspended by a Shaft turning upon a Pin, or otherwise, so as
one man may manage the Hammer, while another holds the Tool or Piercer. If
it be hung in a _Frame_, or other convenient way, he that manageth it hath
no more to do, but to pull it up at first as high as he can, and let it
fall again by its own weight, the motion being so directed, as to be sure
to hit the Piercer right. After the stroke of the Hammer, he that holds the
Piercer, is to turn it a little on its point; so that the Edges or Angles
at the point may all strike upon a new place; and so it must still be
shifted after every stroke, by which means small Chipps will at every
stroke be broken off, which must from time to time be taken out, as need
requires. And thus the work must be continued, till the _Hole_ be 18. or
20. Inches deep, the deeper the better. This _Hole_ being made as deep as
is required, and kept as streight and smooth in the sides, as is possible,
there is then a kind of double _Wedge_ to be made, and {84} fitted exactly
for it; the shape whereof is to be seen in the annexed 3. Figure.

[Illustration]

This double _Wedge_, being 12. or 13. Inches long, each piece of it, and so
made, as being placed in their due position they may make up a _Cylinder_,
but _Diagonal_-wise. The two flat sides that are contiguous, are to be
greased or oyled, that the one may slip the more easily upon the other; and
one of them, which is to be uppermost, having at the great end a hollow
_Crease_ cut into it round about, for fastening a _Cartridge_, full of
_Gunpowder_, to it with a thred, the round end of the _Wedge_ being pared
as much as the thickness of the Paper or Pastboard, that holds the Powder,
needs to make the outside thereof _even_ with the rest of the _Wedge_. This
_Wedge_ must have an Hole drilled through the longest side of it, to be
filled with _priming Powder_, for firing of the Powder in the _Cartridge_;
which needs have no more, than half a pound of Powder, though upon occasion
a greater quantity may be used, as shall be found requisite.

Then this _Wedge_, being first thrust into the Hole with the _Cartridge_,
the round side, whether the Priming-hole is, being uppermost, the other
_Wedge_ is to be thrust in, home to the due position, care being taken,
that they fit the Hole in the Rock as exactly as may be. Then the end of
the lower _Wedge_ being about an Inch longer, than that of the upper
outwardly, and flatned, priming Powder is to be laid upon it; and a piece
of burning _Match_ or _Thread_ dipt in _Brimstone_ or other such prepared
combustible Matter, fastned to it, that may burn so long before it fire the
Powder, as he, that orders it, may have time enough to retire quite out the
Pit or _Adit_, having first placed a piece of Wood or Iron so, as one end
thereof, being set against the end of the lower Wedge, and the other
against the side-wall, so as it cannot slip. Which being done, and the Man
retired, when the Powder comes to take fire, it will first drive out the
uppermost Wedge, as far as it will go, but the slaunting figure of it being
so made, as the farther it goes backward, the thicker it grows, till at the
last it can go no farther, then the {85} fire tears the Rock to get forth,
and so cracks and breaks it all about, that at one time a vast deal of it
will either be quite blown out, or so crackt and broken, as will make it
easie to be remov'd: And according to the effect of one such _Cartridge_,
more may be afterwards made use of, as hath been said.

       *       *       *       *       *

_Observables upon a _Monstrous Head_._

[Illustration]

This was the Head of a _Colt_, represented in the annexed _Figure_ 4. first
viewed by Mr. _Boyle_, who went into the Stable where the _Colt_ lay, and
got the Head hastily and rudely cut off, the _Body_ thereof appearing to
his Eye compleately formed, without any _Monstrosity_ to be taken notice of
in it. Afterwards he caused it to be put into a Vessel, and covered with
_Spirit of Wine_ thereby chiefly intending, to give good example, together
with a proof, that by the help of the said _Spirit_, (which he hath
recommended for such Properties in one of his _Essays_ of the _Usefulness_
of _Natural Philosophy_) the parts of _Animals_, and even _Monsters_, may
in _Summer_ it self be preserved long enough to afford _Anatomists_ the
opportunities of examining them.

The Head being opened, and examined, it was found.

_First_, That it had no sign of any _Nose_ in the usual place, nor had it
any, in any other place of the Head, unless the double Bag CC, that grew
out of the midst of the forehead, were some rudiment of it.

_Next_, That the _two Eyes_ were united into one _Double Eye_, which was
placed just in the middle of the Brow, the Nose being wanting, which should
have separated them, whereby the two Eye-holes in the Scull were united
into one very large round hole, into the midst of which, from the Brain,
entred one pretty large _Optik Nerve_, at the end of which grew a great
_Double Eye_; that is, that _Membrane_, called _Sclerotis_, which contained
both, was one and the same, but seemed to have a _Seam_, {86} by which they
were joined, to go quite round it, and the fore or pellucid part was
distinctly separated into two _Cornea_'s by a white _Seam_ that divided
them. Each _Cornea_ seemed to have its _Iris_, (or Rain-bow-like Circle)
and Apertures or Pupils distinct; and upon opening the _Cornea_, there was
found within it two _Balls_, or _Crystalline Humours_, very well shaped;
but the other parts of it could not be so well distinguished, because the
eye had been much bruised by the handling, and the inner parts confused and
dislocated. It had four Eye-browes, placed in the manner exprest in Figure
4. by a a, b b; a a representing the _lower_, and b b, the _upper_
Eye-lids.

_Lastly_, That just above the Eyes, as it were in the midst of the
Forehead, was a very deep depression, and out of the midst of that grew a
kind of double _Purse_ or _Bagg_, C C, containing little or nothing in it;
but to some it seemed to be a production of the matter designed for the
Nose, but diverted by this Monstrous Conception; perhaps the _Processus
mammillares_ joyned into one, and covered with a thin hairy skin.

       *       *       *       *       *

_Observables in the Body of the _Earl_ of _Balcarres_._

These following Observations, were a while since sent out of _Scotland_ by
an ingenious person, an Eye-witness, to Sir _Robert Moray_.

1. That the Belly of this Nobleman being opened, the _Omentum_ or _Net_ was
found lean and small: his _Liver_ very big; the _Spleen_ big also, filled
with a black and thick humour. His _Stomack_ and _Entralls_ all empty, of a
Saffron-colour, distended with wind only. The _Bladder_ of _Gall_ swelled
with a black humour: The _Kidneys_ filled with a kind of _grumous blood_.

2. That in the _Thorax_ or _Chest_, the _Lobes_ of the _Lungs_ were all
entire, but of a bad colour; on the left side somewhat black and blue, and
on the right, whitish; with a yellowish knob under one of the _Lobes_. {87}

3. That the _Pericardium_ or the _Case_ of the _Heart_ being opened, there
appeared none of that water, in which the _Heart_ uses to swim; and the
external Surface of it, from the _Base_ to the _Tipp_, was not smooth, but
very rough. It being cut asunder, a quantity of white and inspissate
liquour run out, and beneath the _Base_, between the right and left
Ventricle, _two stones_ were found, whereof the one was as bigg as an
_Almond_, the other, _two_ Inches long and _one_ broad, having three
_Auricles_ or crisped _Angles_: And in the Orifice of the right Ventricle,
there was a fleshy fattish Matter.

4. That the whole Body was bloudless, thin, and emaciated, of a black and
bluish Colour.

5. The _Scull_ being opened, both the _Cerebrum_ and _Cerebellum_ were bigg
in proportion to the Body; and out of it run much more Bloud, than was seen
in both the other Regions together.

       *       *       *       *       *

_Of the designed Progress to be made in the _Breeding of Silkworms_, and
the _Making_ of _Silk_, in _France_._

The _French_ King _Henry the Fourth_, having made a general Establishment
all over _France_, of planting and propagating of _Mulberry-trees_, and
_Breeding of Silkworms_, in order to set up and entertain a _Silk-trade_
there; and having prospered so well in that Design, that in many parts of
his Dominions great store of such Trees were raised, and Multitudes of
Silk-works propagated, to the great benefit of the _French_ people,
forasmuch as it was a considerable beginning to avoid the transport of
several Millions abroad for buying of Silks, and withall an excellent means
of well-imploying abundance of poor Orphans and Widows, and many old, lame,
and other indigent and helpless people; The present _French King_, hath
lately revived and seconded that Undertaking by giving express order that
it should be promoted by all possible means, and particularly in the
_Metropolis_ of that Kingdom, and round about it; and that for that end the
whole way concerning that Work and {88} Trade should be fully and
punctually communicated in Print; which hath also been executed by one
_Monsieur Isnard_, in a Treatise published at _Paris_, in _French_,
Intituled, _Instructions for the Planting of White Mulberryes, the Breeding
of Silkworms, and the Ordering of Silk in _Paris_, and the circumjacent
Places_, In which Book, the Method being represented, which that Great
Prince _Henry_ IV used in establishing the said Work and Trade, together
with the success thereof, and the advantages thence derived to his
Subjects, the _Author_, from his own _Experience_, and long _Practice_,
delivers (and seems to do it candidly) all what belongs in this business in
four main heads. _First_, he teaches the Means of sowing, planting, and
raising _White Mulberryes_ (as the Foundation of Silkworks) shewing how
many several wayes _that_ may be done. _Secondly_, The Breeding of
_Silkworms_, the choosing of good Eggs, and their hatching, as also the
Feeding of the _Worms_, and preserving them from sickness, and Curing them
of it, together with the way of making them spin to best advantage.
_Thirdly_, The manner of winding their Silk from their Bottoms, adding the
_Scheme_ of the _Instrument_ serving for that purpose. _Fourthly_, The way
of _keeping_ _Silkworms_ Eggs for the ensuing year.

Through the whole Book are scattered many not inconsiderable particulars,
though perhaps known to most. The _White Mulberry Tree_, as it is in other
qualities preferable to the _Black_, so this _Author_ esteems it the best,
not only for the durableness of the wood, and its large extent of
usefulness in Carpentry and Joyners work; but also for the fitness of its
leaves (besides their principal use for the food of _Silkworms_) to fatten
Sheep, Goats, Cowes, and Hoggs, only by boyling and mingling them with
Bran. The Berryes themselves he commends as very excellent to fatten
Poultry, and to make them lay Eggs plentifully. In the _Changes_,
_Working_, and _Generation_ of this _Insect_, he is very curious to observe
many things. Their _Metamorphoses_, as is known, are four, whereof the form
of the one hath no conformity with any of the rest. The first from an Egge
(of the bigness of a Mustard-seed, and of a darkish Gray Colour, when good)
to a _Worm_ or _Caterpillar_, but of a domestick, noble, and profitable
kind, _Black_, when it first comes {89} forth, but growing _white_ at last;
having 24. feet, 8. on each side of the body, and 4. besides, close to each
side of the head. During this form, they undergo constantly 4. Sicknesses,
in which they cast their Skins, each sickness lasting about 4. days,
wherein they feed not at all; but grow clearer, shorter, and thicker. The
second from a _Worm_ to an _Aurelia_ or _Chrysalis_, having the shape of a
small Plum, whereunto it is transformed after its spinning time is past; in
which state it lies shut up, in hot Countries, for 14. or 15. dayes; in
more temperate ones, 18. or 20. without any Food or Air, known to us.
During which time this _Insect_ leaves two Coats, both that of a _Worm_,
whence 'tis changed into an _Aurelia_, and that of an _Aurelia_, whence it
becomes a _Papilio_ or _Butterfly_, in the _Theca_ or _Case_. The third is,
from an _Aurelia_ to a _Butterfly_, coming out of the _Theca_ with a head,
leggs, and horns; for which passage it makes way by a whitish water, it
casts upon the Silk, which moistning, and thereby in a manner putrefying
it, the new creature thrusts out its head through the sharp end of the
_Case_, by a Hole as big as its self. There is found no Excrement in the
_Case_, but the two Skins only, just now mentioned.

Before they begin to spin, and about the latter end of their feeding, they
must, saith the _Author_, be often changed, and have Air enough, by opening
the Windows of the Room, they are in, if it be not too ill Weather; else,
saith he, the Silk that is in their Belly, will cause so extraordinary a
heat in them, that it burns their gutts, and sometimes bursts them; and the
same (being a substance that resembleth Gum or Burgundy Pitch) will putrefy
and turn into a yellowish matter.

He maketh the best marks of their maturity for spinning to be, when they
begin to quit their white Colour, & their green and yellow Circles, and
grow of the Colour of Flesh, especially upon the tail; having a kind of
_consistent_ softness shewing that they have something substantial in their
Stomachs.

As for their _Working_, he gives this account of it, that the first day
they make only a _Webb_; the second, they form in this _Webb_ their
_Cases_, and cover themselves all over with Silk; the third day, they are
no longer seen, and the dayes following they thicken their _Cases_, alwayes
by one _end_ or _thread_, which they {90} never break off, themselves.
This, he affirms, they put out with so much quickness, and draw it so
subtle and so long, that without an _Hyperbole_, the _end_ or _thread_ of
every _Case_ may have two Leagues in length. He advertiseth, that they must
be by no means interrupted in their work, to the end, that all the Silk,
they have in their bellyes, may come out.

Some eight dayes after they have finished their Work, as many of the best
_Cases_, as are to serve for _seed_, _viz._ the first done the hardest, the
reddest and best coloured, must be chosen, and put a-part; and all
diligence is to be used to winde off the silk with as much speed, as may
be, especially if the _Worms_ have nimbly dispatched their work.

Here he spends a good part of his Book, in giving very particular
Instructions, concerning the way of winding off the silk, setting also down
the form of the Oven and Instruments necessary for that work, which is the
painfullest and nicest of all the rest.

Touching their _Generation_, he prescribeth that there be chosen as many
male as female _Cases_ (which are discerned by this, that the males are
more pointed at both ends of the _Cases_, and the females more obtuse on
the ends, and bigger-bellyed) and that care be had, that no _Cases_ be
taken, but such wherein the _Worms_ are heard rolling; which done, and they
being come forth in the form of _Butterflies_, having four wings, six feet,
two horns, and two very black eyes, and put in a convenient place, the
males fluttering with their wings, will joyn and couple with the females,
after that these have first purged themselves of a kind of reddish humour
by the fundament: in which posture they are to be left from Morning (which
is the ordinary time of their coming forth) till evening, and then the
females are to be gently pulled away, whereupon they will lay their eggs,
having first let fall by the Fundament another humour, esteemed to proceed
from the seed of the males; but the males are then thrown away as useless.
He advertiseth, that if they be coupled longer than 9. or 10. hours, (which
they will be, and that sometimes for 24. hours together, if they be let
alone) either the female will receive very great hurt by it, or much seed
will remain in her belly. {91}

The seed at first coming out is very white, but within a day it becoms
greenish, then red, at last by little and little gray, which colour it
retains alwaies, the most coloured of an obscure gray, being the best;
those grains which never quit their whiteness, having no fecundity in them.

Each female emits ordinarily some 300 grains, more or less, some of them
not being able to render them all, and dying with them in their belly. One
ounce of seed will require an hundred pair of _Cases_, of as many Males as
Females.

Care must be taken, that no Rats, Mice, Ants, or other Vermin, nor any
Hens, or Birds, come near the Seed, they being very greedy to eat them.

This is the substance of what is contained in this _French_ Author,
published at _Paris_ on purpose to promote the _Making_ of _Silk_ there, as
well as it is practised already in other parts of that Kingdom; which is
represented here, to the end, that from this occasion the design, which the
English Nation once did entertain of the _increasing of Mulberry trees_,
and the _Breeding of Silk-worms_, for the _Making of Silk_ within
themselves, may be renewed, and _that_ encouragement given by King _James_
of Glorious memory for that purpose (witness that _Letter_ which he
directed to the Lords Lievtenants of the several shires of _England_) and
seconded by his _Most Excellent Majesty_, that now is, be made use of, for
the honour of _England_ and _Virginia_, and the increase of wealth to the
people thereof; especially since there is cause of hope, that a _double
Silk harvest_ may be made in _one_ Summer in _Virginia_, without hindring
in the least the _Tobacco_-Trade of that Countrey.

       *       *       *       *       *

_Enquiries concerning _Agriculture_._

Whereas the _Royal Society_, in prosecuting the _Improvements of Natural
knowledge_, have it in design, to collect _Histories of Nature and Arts_,
and for that purpose have already, according to the several Inclinations
and Studies of their Members, divided themselves into divers _Commitees_,
to execute the said design: Those Gentlemen, which do constitute the
_Commitee_ for considering of _Agriculture_, and the _History_ and
_Improvement_ thereof, have begun their work with drawing up certain {92}
Heads of _Enquiries_, to be distributed to persons _Experienced in
Husbandry_ all over _England_, _Scotland_, and _Ireland_, for the procuring
a _faithful_ and _solid_ information of the _knowledge_ and _practice_
already obtained and used in these Kingdoms; whereby, besides the aid which
by this means will be given to the general End of collecting the
aforementioned _History_, every place will be advantaged by the helps, that
are found in any, and occasion ministred to consider, what improvements may
be further made in this whole matter. Now to the End, that those
_Enquiries_ may be the more universally known, and those who are skilful in
Husbandry, publickly invited to impart their knowledge herein, for the
_common_ benefit of their Countrey, it hath been thought fit to publish the
_effect_ of them in Print, and withal to desire that what such persons
shall think good from their own _Knowledge_ and _Experience_ to communicate
hereupon, they would be pleased to send it to the Printers of the _Royal
Society_, to be delivered to either of the _Secretaries_ of same. The
Enquiries follow.

1. For _Arable_.

1. The several kinds of the soyls of _England_, being supposed to be,
either Sandy, Gravelly, Stony, Clayie, Chalky, Light mould, Heathy, Marish,
Boggy, Fenny, or Cold weeping Ground; information is desired, what kind of
soyls your Country doth most abound with, and how each of them is prepared,
when employed for _Arable_?

2. What _peculiar_ preparations are made use of to these Soyls for each
kind of Grain; with what kind of Manure they are prepared; when, how, & in
what quantity the Manure is laid on?

3. At what seasons and how often they are ploughed; what kind of Ploughs
are used for several sorts of Ground?

4. How long the several Grounds are let lie fallow?

5. How, and for what productions, _Heathy_ Grounds may be improved? And who
they are (if there be any in your Country) that have reduced _Heaths_ into
profitable Lands?

6. What ground _Marle_ hath over head? How deep generally it lieth from the
surface? What is the depth of the _Marle_ it self? What the colour of it?
Upon what grounds it is used? {93} What time of the year it is to be laid
on? How many loads to an Acre? What Grains _Marled_ Land will bear, and how
many years together? How such _Marled_ Land is to be used afterwards, &c?

7. The kinds of Grain or Seed, usual in _England_, being supposed to be
either Wheat, Miscelane, Rye, Barley, Oats, Pease, Beans, Fitches,
Buck-wheat, Hemp, Flax, Rape; We desire to know, what sorts of Grains are
sown in your Country, and how each of these is prepared for Sowing? Whether
by _steeping_, and in what kind of Liquor? Or by mixing it, and with what?

8. There being many sorts of Wheat, as the White or Red Lammas, the bearded
Kentish Wheat, the gray Wheat, the red or gray Pollard, the Ducks-bill
Wheat, the red-eared-bearded Wheat, &c. And so of Oats, as the common
Black, Blue, Naked, Bearded in _North-wales_: and the like of Barley,
Pease, Beans, &c. The Enquiry is, which of these grow in your Country, and
in what Soyl; and which of them thrive best there; and whether each of them
require a peculiar Tillage; and how they differ in goodness?

9. What are the chief particulars observable in the choice of Seed-Corn,
and all kinds of Grain; and what kinds of Grain are most proper to succeed
one another?

10. What Quantity of each kind is sown upon the Statute-Acre? And in what
season of the Moon and year 'tis sowed?

11. With what instruments they do Harrow, Clod and Rowl, and at what
seasons?

12. How much an Acre of good Corn, well ordered, generally useth to yield,
in very good, in less good, & in the worst years?

13. Some of the common Accidents and Diseases befalling Corn in the growth
of it, being Meldew, Blasting, Smut; what are conceived to be the Causes
thereof, & what the Remedies?

14. There being other Annoyances, the growing Corn is exposed to, as Weeds,
Worms, Flies, Birds, Mice, Moles, &c. how they are remedied?

15. Upon what occasions they use to cut the young Corn in the Blade, or to
seed it; and what are the benefits thereof?

16. What are the seasons and waies of Reaping and Ordering each sort of
Grain, before it be carried off the Ground? {94}

17. What are the several waies of preserving Grain in the Straw, within and
without doors, from all kind of Annoyance, as Mice, Heating, Rain, &c?

18. What are the waies of separating the several sorts of Grain from the
Straw, and of dressing them?

19. What are the waies of preserving any stores of separated Grain, from
the Annoyances they are obnoxious to?

2. For _Meadows_.

1. How the above mentioned sorts of Soyl are prepared, when they are used
for Pasture or Meadow?

2. The common Annoyances of these Pasture or Meadow Grounds being supposed
to be, either Weeds, Moss, Sour-grass, Heath, Fern, Bushes, Bryars,
Brambles, Broom, Rushes, Sedges, Gorse or Furzes: what are the Remedies
thereof?

3. What are the best waies of Drayning Marshes, Boggs, Fenns, &c?

4. What are the several kinds of Grass, and which are counted the best?

5. What are the chief circumstances observable in the Cutting of Grass; and
what in the making and preserving of Hay?

6. What kind of Grass is fittest to be preserved for Winter feeding? And
what Grass is best for Sheep, for Cows, Oxen, Horses, Goats, &c.

       *       *       *       *       *


Advertisement.

_The _Reader_ is hereby advertised, that by reason of the present Contagion
in _London_, which may unhappily cause an interruption aswel of
_Correspondencies_, as of _Publick Meetings_, the Printing of these
_Philosophical Transactions_ may possibly for a while be intermitted;
though endeavours shall be used to continue them, if it may be._

       *       *       *       *       *


_LONDON,_

Printed with Licence, by _John Martyn_, and _James Allestry_, Printers to
the _Royal Society_, at the _Bell_ in St. _Pauls Church-Yard_. 1665.

{95}

       *       *       *       *       *




_Numb._ 6.

PHILOSOPHICAL
_TRANSACTIONS._

       *       *       *       *       *

Monday, _November_ 6. 1665.

       *       *       *       *       *

The Contents.

    _An Account of a not ordinary _Burning Concave_, lately made at
    _Lyons_, and compared with several others made formerly. Of Monsieur
    _Hevelius_ his promise of communicating to the World his Invention of
    making _Optick Glasses_; and of the hopes, given by Monsieur _Christian
    Hugens_ of _Zulichem_, to perform something of the like nature; as also
    of the Expectations, conceived of some Persons in _England_, to improve
    _Telescopes_. An intimation of a way of making more lively Counterfeits
    of Nature in _Wax_, then are extant in _Painting_; and of a new kind of
    _Maps_ in a low _Relievo_, or _Sculpture_, both practised in _France_.
    Some _Anatomical_ Observations of Milk found in Veins instead of Blood;
    and of Grass found in the Wind-pipes of some Animals. Of a place in
    _England_, where, without Petrifying Water, Wood is turned into Stone.
    Of the nature of a certain Stone, found in the _Indies_ in the head of
    a _Serpent_. Of the way, used in the _Mogol's_ Dominions, to make
    _Salt-petre_. An Account of _Hevelius_ his _Prodromus Cometicus_, and
    of some Animadversions made upon it by a _French_ Philosopher; as also
    of the Jesuit _Kircher_'s _Mundus Subterraneus_._

       *       *       *       *       *

_An Account of a not ordinary _Burning Concave_, lately made at _Lyons_,
and compared with several others made formerly._

An opportunity being presented to revive the publishing of these Papers,
which for some Moneths hath been {96} discontinued by reason of the great
Mortality in _London_, where they were begun to be Printed; it hath been
thought fit to embrace the same, and to make use thereof for the gratifying
of the Curious, that have been pleased to think well of such
Communications: To re-enter whereupon, there offers it self, first of all a
Relation of an uncommon _Burning-glass_, not long since made in _France_,
in the City of _Lyons_, by one called Monsieur _de Vilette_, as it was sent
to the Publisher of these Tracts, in two Letters, whereof the one was in
_Latine_, the other in French, to this effect.

Concerning the Efficacy of Monsieur _de Villete_ his Burning Glass, all
what the _P. Bertet_ hath written of it, is true. We have seen the effects
of it repeated over and over again, in the Morning, at Noon, and in the
Afternoon, alwaies performing very powerfully; burning or melting any
Matter, very few excepted. The _Figure_ of it is round, being thirty
Inches, and somewhat better in _Diameter_. On one side it hath a Frame of a
Circle of Steel, to the end that it may keep its just Measure: 'Tis easie
to remove it from place to place, though it be above an hundred weight, and
'tis easily put in all sorts of postures. The _burning Point_ is distant
from the Centre of the Glass, about three Feet. The _Focus_ is about half a
_Louys d'or_ large. One may pass ones hand through it, if it be done
nimbly; for if it stay there the time of a second Minute, there is danger
of receiving much hurt.

_Green wood_ takes fire in it, in an instant, as do also many other Bodies.

  A small peice of _Pot-Iron_ was melted, and                _Seconds_
    ready to drop down, in                                      40.
  A _Silver Peice_ of 15 _Pence_ was pierced, in                24.
  A _gross Nail_ (called _le Claude paisan_) was melted, in     30.
  The end of a _Sword-blade_ of _Olinde_, was burn'd, in        43.
  A _Brass Counter_ was pierced, in                             06.
  A piece of _red Copper_ was melted ready to drop down, in     42.
  {97}
  A peice of a _Chamber Quarry-stone_ was vitrified,
    and put into a Glass-drop, in                               45.
  _Steel_, whereof Watch-makers make their springs,
    was found melted, in                                        09.
  A _Mineral-Stone_, such as is used in Harquebusses
    _à rovët_, was calcin'd and vitrified, in                   1. _just._
  A peice of _Morter_ was vitrified, in                         52.

In short, there is hardly any Body, which is not destroyed by this Fire. If
one would melt it by it any great quantity of Mettal, that would require
much time, the Action of Burning not being perform'd but within the bigness
of the _Focus_, so that ordinarily none but small pieces are exposed to it.
One Mounsieur _de Alibert_ buys it, paying for it Fifteen hundred Livers.

Since this Information, there were, upon occasion given from thence, upon
the same subject, further communicated from _Paris_ the following
Particulars.

I see by two of the Letters, that you incline to believe, the Glasses of
_Maginus_ and _Septalius_ do approach to that of _Lyons_: But I can assure
you, they come very far short of it. You may consult _Maginus_ his Book,
where he describes his; and there are some persons here that have seen one
of his best, which had but about twenty Inches Diameter; so that this of
_Lyons_ must perform at least twice as much. As to _Septalius_, we expect
the Relations of it from Intelligent and Impartial men. It cannot well be
compared to that of _Lyons_: but in bigness; and in this case, if it have
five _Palms_ (as you say) that would be about 3½ feet _French_, and so it
were a Foot bigger, which would make it half as much greater in surface:
But as to the Effects, seeing it burns so far off, they cannot be very
violent. And I have heard one say, that had seen it, that it did not set
Wood on Fire but after the time of saying a _Miserere_. You may judge of
the difference of the Effects, since that of _Lyons_ gathers its Beams
together within the space of seven or eight _Lines_; {98} and that of
_Septalius_ must scatter them in the compass of three Inches. Some here do
intend to make of them yea and bigger ones; but we must stay till they be
done, &c.

       *       *       *       *       *

Of _Monsieur _Hevelius_'s Promise of imparting to the World his Invention
of making _Optick Glasses_; and of the hopes given by Monsieur _Hugens_ of
_Zulichem_, to perform something of the like nature; as also of the
Expectations, conceived of some Ingenious Persons in _England_ to improve_
Telescopes.

That eminent Astronomer of _Dantzick_, Monsieur _Hevelius_, writes to his
Correspondent in _London_, as followeth:

What hath been done in the grinding of Optick-glasses in your parts, and
how those beginnings, mentioned by you formerly, do continue and succeed, I
very much covet to hear, 'Tis now above Ten Years, since I my self invented
a peculiar way of grinding such Glasses, and reduced it also into practice;
by which 'tis easie, without any considerable danger of failing, to make
and polish Optick-glasses of any _Conick_ Section, and that (which is most
notable) in any dish of any Section of a _Sphere_: which Invention I have
as yet discovered to none, my purpose being, for the Improvement of Natural
Knowledge, to describe the whole method thereof in my _Celestial Machine_,
and to propose it to the Examination and Judgment of the _Royal Society_;
not doubting at all, but they will find the way true and practicable, my
self having already made several Glasses by it, which many Learned Men have
seen and tryed.

Monsieur _Hugens_, inquiring also in a Letter, newly written by him to a
Friend of his in _England_, of the success of the attempts made by an
ingenious _English_ Man for perfecting such Glasses, and urging the
prosecution of the same, {99} so as to shew by the effects the
practicableness of the Invention, mentions thereupon, That he intends very
shortly to try something in that kind, of the success whereof he declares
to have good hopes.

Monsieur _du Son_, that excellent Mechanician, doth also at this very
present employ himself in _London_, to bring _Telescopes_ to perfection, by
grinding Glasses of a _Parabolical_ Figure, by the means whereof he hopes
to enable the Curious to discover more by a Tube of one Foot long, or
thereabouts, furnished with Glasses thus figured, then can be done by any
other Tubes of very many times more that length: The success hereof will
('tis thought) shortly appear.

       *       *       *       *       *

_An Advertisement of a way of making more lively Counterfeits of Nature in
_Wax_, then are extant in _Painting_: And of a new kind of _Maps_ in a low
_Relievo_. Both practised in_ France.

This was communicated by the Ingenious Mr. _John Evelyn_, to whom it was
sent from _Paris_ is a Letter, as followeth.

Here is in our Neighbourhood a _French-man_, who makes more lively
Counterfeits of Nature in _Wax_, then ever I yet saw in _Painting_, haveing
an extraordinary address in modelling the Figures, and mixing the Colours
and Shadows; making the Eyes so lively, that they kill all things of this
Art I ever beheld; He pretends to make a visit into _England_ with some of
his Peices.

I have also seen a new kind of _Maps_ in low _Relievo_, or Sculpture; For
example the Isle of _Antibe_, upon a square of about eight Foot, made of
Boards, with a Frame like a Picture: There is represented the Sea, with
Ships and other Vessels Artificially made, with their _Canons_ and Tackle
of Wood fixed upon the surface, after a new and most admirable manner. The
Rocks about the Island exactly form'd, {100} as they are upon the Natural
Place; and the Island it self, with all its Inequalities, and Hills and
Dales; the Town, the Forts, the little Houses, Platform, and Canons
mounted; and even the Gardens and Platforms of Trees, with their green
leaves standing upright, at if they were growing in their Natural Colours:
in _fine_, Men, Beasts, and whatever you may imagine to have any
protuberancy above the level of the Sea. This new, delightful, and most
instructive form of _Map_, or _Wooden Country_, you are to look upon either
_Horizontally_, or _side-long_, and it affords equally a very pleasant
object.

       *       *       *       *       *

_Some _Anatomical_ Observations of Milk found in Veins, instead of Blood;
and of Grass, found in the Wind-pipes of some _Animals_._

A curious Person wrote not long since from _Paris_, that there they had, in
the house of a Physitian, newly open'd a Mans Vein, wherein they found
_Milk_, instead of _Blood_. This being imparted to Mr. _Boyle_ at _Oxford_,
his Answer was, That the like Observation about _White Blood_, had been
made by a Learned Physitian of his acquaintance, and the thing being by him
look'd upon as remarkable, he was desirous to have it very circumstantially
from the said Physitian himself, before he would say more of it. The next
Moneth may bring us in this Account.

The other Particular, mention'd in the Title of this Head, came in a Letter
sent also by Mr. _Boyle_, in these words:

I shall acquaint you, That Two very Ingenious Men, Dr. _Clark_, and Dr.
_Lower_, were pleased to give me an account of a pretty odd kind of
Observation: One of them assuring me, That he had several times, in the
_Lungs_ of _Sheep_, found considerable quantity of Grass in the very
Branches of the _Aspera Arteria_: And the other relating to me, That a few
Weeks since, he, and a couple of {101} Physitians, were invited to look
upon an Ox, that had for two or three daies almost continually held his
Neck streight up, and was dead of a Disease, the owner could not conjecture
at; whereupon the parts belonging to the Neck and Throat, being open'd,
they found, to their wounder, the _Aspera Arteria_ in its very Trunk all
stuff'd with Grass as if it had been thrust there by main force: which
gives us a just cause of marvelling and inquiring, both how such a quantity
of Grass should get in there; and how, being there, such an Animal could
live with it so long.

       *       *       *       *       *

_Of a place in _England_, where, without petrifying Water, Wood is turned
into Stone._

The same Searcher of Nature, that was alledged in the immediately precedent
Observations, did impart also the following, in another Letter from
_Oxford_, where he saith,

I was a while since visited by a Gentleman, who tells me, That he met with
a place in these parts of _England_, where, though there be no petrifying
Spring (for that I particularly asked) Wood is turned into Stone in the
_Sandy Earth_ it self, after a better manner then by any Water I have yet
seen: For I had the Curiosity to go to look upon peices of Wood, he brought
thence, and hope for the opportunity of making some tryals to examine the
matter a little further, then I have yet been able to do. _Thus far that
Letter._

Since which time, He was pleased to give this further Information of the
same matter, with a _Mantissa_ of some other Particulars, belonging to this
Subject, in these Words.

I was lately making some Tryals with the Petrifyed Wood I told you off,
which I find to be a very odde substance, wonderfully hard and fixed. If I
had opportunity to Re-print the _History of Fluidity_ and _Firmness_, I
could add divers things about _Stones_, that perhaps would not be disliked;
and I hope, if God vouchsafe me a little leisure, {102} to insert several
of them in fit places of that _History_, against the next Edition. Here is
a certain Stone, that is thought to be Petrifyed Bone, being in shap'd like
a Bone, with the Marrow taken out; but with a fit _Menstruum_, I found that
I could easily dissolve it, like other soft Stones: and possibly it may
prove as fit as _Osteocolla_, for the same Medicinal uses.

       *       *       *       *       *

_Of the nature of a certain Stone, found in the _Indies_, in the head of a
_Serpent_._

There was, some while ago, sent by Sir _Philiberto Vernatti_, from _Java
major_, where he resides, to Sir _Robert Moray_, for the Repository of the
_Royal Society_, a certain Stone, affirmed by the presenter to be found in
the Head of a _Snake_, which laid upon any Wound, made by any venomous
Creature, is said to stick to it, and to draw away all Poyson: and then,
being put in Milk, to void its Poyson therein, and to make the Milk turn
blew; in which manner it must be used, till the Wound be cleansed.

The like Relations having been made, by several others, of such a Stone,
and some also in this City affirming, to have made the Experiment with
success, it was thought worth while, to inquire further into the truth of
this Matter: since which time, nothing hath been met with but an
Information, delivered by that Ingenious _Parisian_, Monsieur _Thevenot_,
in his second _Tome_, of the _Relations of divers considerable Voyages_,
whereof he lately presented some Exemplars to his Friends in _England_. The
Book being in French, and not common, 'tis conceived it will not be amiss
to insert here the said Information, which is to this effect:

In the _East Indies_ and in the Kingdom of _Quamsy_ in _China_, there is
found a Stone in the Head of a certain _Serpent_ (which they call by a name
signifying _Hairy Serpents_) which heals the bitings of the same Serpent,
that else would kill in 24 hours. This Stone is round, white in the middle
and about the {103} edges blew or greenish. Being applyed to the Wound, it
adheres to it of it self, and falls not off, but after it hath sucked the
Poyson, then they wash it in Milk, wherein 'tis left awhile, till it return
to its natural condition. It is a rare Stone, for if it be put the second
time upon the Wound, and stick to it, 'tis a sign it had not suck'd all the
Venome during its first application, but if it stick not, 'tis a mark that
all the Poyson was drawn out at first. So far our _French_ Author: wherein
appears no considerable difference from the written Relation before
mentioned.

       *       *       *       *       *

_Of the way, used in the _Mogol_'s Dominions, to make _Saltpetre_._

This is delivered in the same Book of Monsieur _Thevenot_, and the manner
of it having been inquired after, by several curious Persons, to compare it
with that which is used in _Europe_, 'tis presum'd, they will not be
displeased to find it inserted here in _English_, which is as followeth:

_Saltpetre_ is found in many places of the _East-Indies_, but cheifly about
_Agra_, and in the Villages, that heretofore have been numerously
inhabited, but are now deserted. They draw it out of three sorts of Earth,
black, yellow, and white: the best is that which is drawn out of the black,
for it is free from _common_ Salt. They work it in this manner: They make
two Pits, flat at the bottom, like those wherein common Salt is made; one
of them having much more compass than the other, they fill _that_ with
Earth, upon which they let run Water, and by the feet of People they tread
it, and reduce it to the consistency of a Pap, and so they let it stand for
two daies, that the Water may extract all the Salt that is in the Earth:
Then they pass this Water into another Pit, in which it christallizes into
_Saltpetre_, They let it boil once or twice in a Caldron, according as they
will have it whiter and purer. Whilest it is over the Fire, they scum it
continually, and fill it out into great Earthen Pots, which {104} hold each
25 or 30 pounds, and these they expose to clear Nights; and if there be any
impurity remaining, it will fall to the bottom: Afterwards they break the
Pots, and dry the Salt in the Sun. One might make vast quantities of
Saltpetre in these parts; but the Country people feeling that _We_ buy of
it, and that the _English_ begin to do the same, they now sell us a _Maon_
of 6 pounds for two _Rupias_ and a half, which we had formerly for half
that price.

       *       *       *       *       *

_An account of _Hevelius_ his _Prodromus Cometicus_, together with some
Animadversions made upon it by a _French_ Philosopher._

This excellent _Dantiscan_ Astronomer, _Hevelius_, in his _Prodromus_ (by
him so call'd, because it is as a Harbinger to his _Cometography_, which
hath already so far passed the Press, that of twelve Books there are but
three remaining to be Printed) gives an account of the Observations he hath
made of the _First_ of the two late Comets; reserving those he hath made of
the _second_, for that great Treatise, where he also intends to deliver the
Matter of this _first_ more particularly, and more fully than he hath done
here.

In this Account he represents the Rise, Place, Course, Swiftness, Faces and
Train of this Comet, interweaving his Conceptions both about the Region of
Comets in general (whether in the _Air_, or the _Æther_?) and the Causes of
their Generation: In the search of which latter, he intimates to have
received much assistance from his _Telescope_.

He observes this Comet not before _Decemb._ 4/14, (though he conceives it
might have been seen since _Novemb._ 23 _st. n._) & he saw it no longer
then _Feb._ 3/13: though several others have seen it both sooner, and
later: and though himself continued to look out for it till _March_ 7. _st.
n._ but fruitlesly, whereof he thinks the reason to have been its too great
distance and tenuity.

{105}

He finds, its apparent Motion was not made in a _Just_ great Circle, but
deviated considerably from it; and conceives, that every Comet falls to
this deviation, when this apparent Motion grows slow, and the Star becomes
Stationary (which, as he saith, it doth in respect of the _Ecliptick_, not
its own _Orbite_,) Here he observes, That from _Decemb._ 8/18, to _Decem._
30. _Jan._ 9. its course was almost a great Circle: but that _then_ it
began to deflect from that Circle towards the _North_; so that afterwards,
with a very notable and conspicuous Curvity, it directed its course towards
_Primam Arietis_: Of which deflection, he ventures to assign the cause from
the Cometical Matter, the various position and the distance of the Comet
from the Earth and the Sun, the annual Motion of the Earth, and the
impressed Motion, and the inclination of the _discus_ of the Cometical
Body.

He is pretty positive, that without the _annual Motion_ of the _Earth_, no
rational Account can be given of any Comet, but that all is involved with
perplexities, and deform'd by absurdities.

He inquires, since all Comets have the peculiar _Ingenite_ Motion, what
kind of Line it is, they describe by that Motion of their own? whether
circular, or streight, or curve, or partly streight and partly curve? And
if curve, whether regular or irregular? if regular, whether Elliptick, or
Parabolar, or Hyperbolical? He answers, That this Motion is _Conical_; and
judgeth, that by the _Conick_ path all the _Phænomena_ of Comets can,
without any inconveniency, be ready solved; even of that, which (by
History) in fifty daies, passed through more then the 12 Signs in the
_Zodiack_: And of that, which in two daies ran through eight Signs: and of
another, which in 48 daies posted through all the Signs, _contra seriem_.
Which how it can be explicated upon the supposition of the Earths standing
still, and upon the denying of the annual Motion thereof, he understands
not at all. {106}

He refers to his _Cometography_ these Disquisitions: whether all Comets (in
their innate Motion) move equal _spaces_ in equal _Times_? which is the
swiftest, and which the slowest Motion they are capable of? what the cause
of this acceleration and retardation of their true Motion?

He puts it out of doubt, that they are in the _Sky_ it self, producing
reasons for it that are very considerable, and alledging amongst others,
That the _Parallaxes_ doe clearly evince it, which he finds far less in
Comets, then in the _Moon_, yea then sometimes in the _Sun_ it self. Where
he also represents, That he hath deduced the _Horizontal Parallax_ of this
very Comet from one onely Observation, made _Feb._ 4. _st. n._ by which he
found, That then it was distant from the Earth 5000 Semidiameters of the
same, or 4300000 _German_ miles. From this distance from the earth, he
deduces, That on that Day when it was so remote from the Earth, its true
_Diameter_ was 2560 _German_ miles, which is three times bigger then the
Diameter of the Earth, and almost six times bigger then that of the Moon,
whose Diameter, according to his _Theory_, is 442 _German_ miles.

He finds the _Matter_ of Comets to be in the _Æther_ it self, making the
_Æther_ and the _Air_ to differ only in purity, and esteeming, That the
_Planets_ do emit their Exhalations, and have their _Atmospheres_ like unto
our Earth. Where he affirms, That the Sun alone may cast out so much Matter
at any time in one year, as that thence shall be produced not one or two
Comets, equallizing the Moon in Diamiter, but very many; which if so, what
contribution may not be expected from the other Planets?

Of this Cometical Matter, he thinks, That first it is by little and little
gathered together, then coagulated and condensed, and thereby reduced to a
less Diameter; but then, after a while it resolves again, and grows dilute
and pale, and at last is dissipated. And accordingly he affirms, That he
hath observed the Head of this Comet at first more confused, thin and pale,
afterwards clearer and clearer. {107}

He conceives, That all Comets do respect the _Sun_ as their _King_ and
_Centre_, as _Planets_ do, making them a kind of _Spurious Planets_, that
emulate the _true_ ones in their Motion almost in all things.

The _Train_, he makes nothing else but the Beams of the Sun, falling on the
head of the Comet, and passing through the same, refracted and reflected.
And amongst his _Observations_ and _Schemes_ of this Comet, there occurs
one, wherein the Tail is _curve_, so seen by him _Decemb._ 11/21. He
assigns the causes why the Trains do so much vary, and shews also, on what
depends their length.

Whether the _same_ Comet returns again, as the Spots in the Sun? and,
whether in the time of great _Conjunctions_ they are more easily generated?
and whether they can be certainly foretold? with several other Inquiries,
he refers for to his _great Book_.

As to _Prognostications_, he somewhat complains, That men do more inquire
what Comets _signifie_, then what they _are_, or how they are generated and
moved; professing himself to be of the mind of those that would have Comets
rather _admired_ then _feared_; there appearing indeed no cogent reason,
why the Author of Nature may not intend them rather as Monitors of his
_Glory_ and _Greatness_, then of his _Anger_ or _Displeasure_; especially
seeing that some very diligent Men (among whom is _Gemma Frisius_) take
notice of as great a number of _good_ as _bad_ Events, consequent to
Comets. _Seneca_ also relating, That that Comet which appeared in his time,
was so happy, that it did _Cometis detrahere infamiam_, it cleared the
credit of Comets, and made People have good thoughts of them.

Having given some Account of what may be look'd for in this _Prodromus_, it
follows, That some also should be rendred of the _Animadversions_ mention'd
to have been made upon the same. This was done by that _Parisian_
Philosopher Monsieur _Auzout_, in a Letter of his to his Country-man
Monsieur _Petit_; in which he strongly conceives, That this {108}
_Prodromus_ contains some mistakes, of which he chiefly singles out one, as
most considerable, in _Hevelius_'s Observation of _Feb._ 8/18, and declares
thereupon, That he, and several very intilligent Astronomers of _France_
and _Italy_ concurring with him therein, (whereas M. _Hevelius_ to him
seems to stand single, as to this particular) found by their Observations,
That this Comet could not, on that day of _February_, be there where M.
_Hevelius_ placeth it, _viz._ In _Prima Arietis_; unless it be said, That
it visited that Star of _Aries_ on the 18, and returned thence the 19^{th},
into its ordinary course; in which, according to his, and his several
Correspondents Observations the Comet on _Feb._ 17. was distant from that
_first Star_ of _Aries_ at least 1 degree and 17 minutes; and on _February_
19. (he having missed, as well as his other Friends, the Observation on
_Febr._ 18) was advanced in its way 12 or 13 minutes, but yet distant from
the said Star _some minutes_ above a _whole degree_, and consequently far
from having then passed it. After which time M. _Auzout_ affirms to have
seen it as well as several others, for many daies, and that until _March_
7/17, observing, That about _Feb._ 26. or 27, when the Comet was nearest to
the often-mentioned _first_ of _Aries_, it approached not nearer thereunto,
then the distance of 50. minutes.

This important Difference between two very Learned, and very deserving
Persons, being come to the knowledge of some of the ablest _Philosophers_ &
_Astronomers_ of _England_, hath been by them thought worthy their
Examination: and they being at this very present employed in the discussion
thereof, by comparing what hath been done and published by the Dissenters,
and by confronting with them their own Domestick Observations, are very
likely to discern where the mistake lies; and having discern'd it, will
certainly be found hightly impartial and ingenuous in giving their sense of
the same. {109}

       *       *       *       *       *

_Of the _Mundus Subterraneus_ of _Athanasius Kircher_._

This long expected _Subterraneous World_, is now come to light, dedicated
(at least the _Exemplar_, that hath been perused by the _Publisher_ of
these _Papers_, who hears, That other _Copies_ bear Dedication to other
_Great Princes_) both to the present Pope, as being esteemed by the author
to have a part of his _Apostolical Kingdom_ there; and to the _Roman
Emperor_ now Regent, who indeed in his Kingdom of _Hungary_, and in several
Provinces of _Germany_, hath very many and very considerable things, worthy
to be observed, under _Ground_.

To give the Curious a taste of the _Contents_ of this _Volume_, and thereby
to excite them to a farther search into the recesses of Nature, for the
composure of a good _Natural History_; they may first take notice, That the
Author, having given an account in the _Preface_, what encouragement he
received, for writing this Book, from the opportunity of Travelling with
the _Cardinal_ of _Hassia_ into _Sicily_ (in which Voyage, he saith, He met
with, as it were, an _Epitome_ of what may be observable in the
Subterraneous parts of the Earth; and in particular, with an Earth-quake of
14 daies duration, very instructive to him concerning several great Secrets
of Nature:) having I say, thus Prefaced, he divided his Work into 12
_Books_, wherein he affirms not only to have explicated the Divine
Structure of the under-ground World, and the wondrous distribution of the
Work-houses of Nature, and her Majesty and Riches therein; but also to have
opened the Causes of her Effects and Productions; whence, by the Marriage
of Nature and Art, a happy Issue may follow for the use and benefit of
Humane Life.

In the _First_ Book, he considers the nature of the Centre of the Earth,
where he delivers several _Paradoxes_ touching the same, and Discourses of
the Motion of heavy Bodies, of Pendulems, of Projectils. {110}

In the _second_ he treats of the Fabrick of the _Terrestrial Globe_, of the
Influences it receives from the Coelestial Bodies, especially the _Sun_ and
_Moon_, of both which _Luminaries_ he gives a _Scheme_; of the proportion
of the Earth to the Sun and Moon; of the external conformation of the
Earth, its Mountains, and their concatenations, decrease and increase,
together with the strange transformation thereof. Further, of the Waters
encompassing the Earth, and their various Communications by hidden
Passages; as also the heighth of Mountains, and of the depth of Seas; the
dimension of the _Sicilian Straights_; the Magnetical Constitution of the
Earth, its Heterogeneous Nature, Interior Frame, Laboratories, Caves,
Channels, &c.

In the _third_: Of the Nature of the Ocean, and the diversity of its
Motions; of its general Motion from the _East_ to _West_, Currents;
Reciprocations, Gulfs, Whirle-pools, Saltness, &c.

In the _fourth_: Of the Nature of the Subterraneous _Fire_, its necessity,
diffusiveness, food, prodigious Effects through ignivomous Mountains; as
also of the Nature of _Air_, and _Winds_, their power and variety; of the
general Wind, how and whence generated; of Periodical and Anniversary
Winds, and their Causes; as also of the production of Artificial Winds, for
refreshment and other advantages. To which he subjoyns a Discourse, tending
to prove, That all Meteors owe their Nativity to the Fiers of the
Subterraneous World.

In the _fifth_: Of the Original of Springs, Rivers, Lakes; various
differences and qualities of Waters, and the marks where they are to be met
with under Ground; of Waters _Medical_, hot Baths, and their Differences,
Causes, Virtues; together with the Wonderful Qualities and Proprieties of
some Springs, as to their Colour, Taste, Smell, Weight, Salubrity, Flux and
reflux, Petrifying power, &c.

In the _sixth_: Of the _Earth_ it self, and the great variety contained in
the Womb thereof; of the manifold Productions {111} made therein, by the
virtue of Salt and its Auxiliaries, the differences whereof are largly
discoursed of, together with the way of extracting the same. In particular
of _Saltpetre_, its Generation, Nature, Virtues; of the way of making
_Gunpowder_, and the various uses thereof, as also the Nature, Qualities,
Preparation, Medicinal and other uses of _Alume_ and _Vitriol_.

In the _Seventh_: Of some _Fossils_, as Sand, Gravel, Earths, and their
various Differences, Qualities, uses Economical, Chymical, Medical:
together with the strange varieties & changes happening in the Earth, and
their causes; as also the requisits to _Agriculture_.

In the _eight_: First, of _Stones_, their Origine, Concretion, difference
of Colours; and in particular, of _Gems_ and their variety, causes of
generation, transparency in some and colours in others; as also of their
various Figures and Pictures by Nature framed both in common and precious
Stones, with their Causes. Secondly, of the Transformation of Juices,
Salts, Plants, yea of Beasts and Men turn'd into Stone: together with the
generation of Bony Substances under ground, by many esteemed to be the
Bones of _Gyants_; and of _Horny_ Substances, taken for _Unicorns_ horns:
as also of _Fossile wood_ and _Coals_, Thirdly, of _Bituminous Flowers,
lapis Asbestos, Amber_, and its _Electrical_ virtue; together with the way
how Insects, little Fishes, and Plants are Intombed therein. Fourthly; of
Subterraneous _Animals_, Moles, Mice, Birds, Dragons; where is also
treated, of those Animals that are found in the midst of Stones.

In the _ninth_; First, of Poysons, their primeval Origine from Minerals,
and their accidental Generation in Vegetable and Animal Bodies, together
with their differences; where 'tis discoursed, not only how Poysons may be
bred in Men, but also, how the Poyfons of some Animals do infect and kill
Men; and, where the Venom of Vipers lodges, and how mad _Dogs_ and
_Tarantula's_ so communicate their Poyson, as that it exserts not its
noxiousness, till after some {112} time: Where also occasion is taken to
discourse on the Original of Diseases, and cure of Poysonous ones.
Secondly, of the wonderful Nature of _Sulphur, Antimony, Quick-silver_,
their origine and qualities; together with the productions of _Corals_ and
_Pearls_.

In the _tenth_: First of _Metallurgy_, and the way how that unctuous Body,
out of which mettals are produced, is elaborated by Nature, and what
therein are _Sulphur, Salt_, and _Mercury_; besides, what it is that
renders Mettals fluid in the Fire, but not Stones and Vegetables, &c.
Secondly, of the Requisits to a perfect knowledge of the _Metallick Art_,
and of the Qualities of the _Mine-master_; then of the Diseases of
Mine-men, and their Cure, and the waies of purging the Mines of the Airs
malignity; as also of _Metallognomy_, or the signs of latent Mettals, and
by what Art they may be discovered. Thirdly, several Accounts sent to the
Author, upon his Inquiries by the Mine-masters themselves, or other cheif
Over-seers of the Mine-works, touching the variety, nature and properties
of Minerals, and the many Accidents happening in Mines, particularly the
_Hungarian_ ones at _Schemnitz_, and those of _Tyrol_. Fourthly, of several
both _Hydraulick_ and _Wind-Engines_, to free the Mines from Water and
noxious damps. Fiftly, Of the way of working Mettals, Gold, Silver, Copper,
Iron, and particularly of the method used at _Potosi_ in _Peru_, of
extracting the Silver out of the Mineral: to which is added, a Discourse of
_Salt-pits_, and the way of making Salt.

In the _eleventh_, First, of _Alchimy_, its Original and Antiquity, the
Vessels and Instruments belonging thereunto. Secondly, of the _Philosophers
Stone_, what is meant by it, and whether by means thereof true Gold can be
produced? And in general, whether there be any such thing, as a true and
real Transmutation of one Mettal into another? Where are delivered the
several Processes of the reputed _Adepti, Raymund Lulle, Azoth, Arnold de
Villanova, Paracelsus, Sendivogius, &c._ but all exploded as fals and
deceitful. Thirdly, {113} of the decisions in Law concerning Chimical Gold,
true or fals. Fourthly, what the celebrated _Philosophers Stone_ was among
the Ancients, and what they understood by the same?

In the _twelfth_: First, Of the _Seminal Principle_ of all things, its
origine, nature and property; of the way how Nature proceeds in the
Generation of _Minerals, Vegetables, Animals_; of Spontaneous Generation;
of _Zeophyts, Insects_ of all sorts, and particularly of the Worms bred in
Men; together with the causes why Nature would produce such swarms of
infinite sorts of Insects. Secondly, of the variety and differences of
_Vegetables_; of the requisits to know the _virtues_ of _Plants_, and of
the several waies of _Engrafting_. Thirdly, of the _Art of Distilling_,
whereby Nature is imitated, as doing all her under-ground works, in the
Opinion of this Author, by _Distillation_. Fourthly, of the _Laboratories
of various Arts_, in which, according to Natures pattern, used in her
Subterraneous Operations, strange things may be performed: where treating
of _Chymical Secrets_, the truth of the Preparation of _Aurum potabile_ is
discussed, and the _Magisteries_ of Gold, Silver, Iron, Tin, Copper and
Lead, examined: to which is subjoyned an _Appendix_, furnishing such Rules,
whereby Students in _Chymistry_ may be directed in their work, and true
Operations distinguished from fals ones. Fiftly, Of _Metallostaticks_,
where by the mixture of Mettals and Minerals may be certainly known;
together with a way of weighing the Proportions of _moist_ and _dry_,
existent in every Compound, as well Vegetable and Animal, as Mineral.
Sixthly, of _Glass-making_, where is treated of the Nature of _Glass_; of
the Artificial Production of all sorts of Precious Stones, partly from the
Authors own Experiments, partly from the Communication of his Friends, and
the Collection of the best Writers upon that subject. Seventhly, of
_Fire-works_, where the Invention and Preparation of Gunpowder is largely
discoursed of, and the waies of making _Squibs, Fires burning in Water_,
{114} and many others, used in Publick Festivities, are described.
Eighthly, of some _Mechanical Arts_, as that of _Gold-smiths, Black smiths,
Copper smiths, Wyre-drawers_, in the last whereof he resolves this
_Problem_; a certain weight of Mettal, and the bigness of the hole, through
which the Wyre is to be drawn, being given, to find into what length so
much Mettal can be spun out.

Thus you have a view of this whole _Volume_; to which it may perhaps not be
amiss to adde, for a Conclusion, some of those Particulars which are
esteemed by the Authour to out-shine the rest, and are here and there
inter-woven as such. For example, in the _First Part_.

The use of _Pindules_, for knowing by their means the _state_ of ones
_Health_, from the different beatings of the _Pulse_, p. 51.

The _Chain_ of _Mountains_, so drawn over the Earth, that they make, as it
were, an _Axis_, passing from _Pole_ to _Pole_; and several transverse
_ductus_, so cutting that _Axis_, as to make, in a manner, an _Equator_ and
_Tropicks_ of Mountains: by which concatenation he imagines, That the
several parts of the Earth are bound together for more firmness, p. 69.

A Relation of a strange _Diver_, by his continual converse in Water, so
degenerated from himself, That he was grown more like an _Amphibium_, than
a man, who, by the command of a _Sicilian_ King, went down to the bottom of
_Charibdis_, and brought a remarkable account of the condition of that
place, p. 98.

A Description of the Origine of the _Nile_, as this Author found it in a
certain _MS._ of one of his own _Society_, called _Peter Pais_, whom he
affirms to have been an Eye-witness, and to have visited the Head of the
_Emperor of Æthiopia_ himself _Anno_ 1618. which _Manuscript_, he saith,
was brought to _Rome_, out of _Africa_, by their _Procurator_ of _India_
and _Æthiopia, p._ 72. {115}

The _Communication_ of the _Seas_ with one another by Subterraneous
Passages, _viz._ of the _Caspian_, with the _Pont Euxin_ and the _Persian
Gulf_; of the _Mare Mortuum_, with the _Mare Rubrum_, and of this latter
with the _Mediterranean_; as also of _Scylla_ with _Charybdis_, p. 85. 101.

The Subterraneous _Store-houses_ (in all the four parts of the Earth) of
_Water_, and _Fire_, and _Air_; together with their important Uses, p. 111.

An account of the state of the Earth about the _Poles_, how the Waters are
continually swallowed up by the _Northern_, and running along through the
Bowels of the Earth, do regurgitate at the _Southern Pole_, p. 159.

A description of Mount _Vesuvius_ and _Ætna_, both visited by the Author
himself, _Anno_ 1638. their Dimensions, Communication, Incendiums, Paths of
Fiery Torrents cast out by them, &c. as also of the _Vulcans_ in _Iceland_
and _Groenland_, and their Correspondence and Effects. p. 180.

An Account of that famous and strange _Whirl-pool_ upon the Coasts of
_Norway_: commonly call'd _The Maelstrom_; which the Author fancies to have
Communication, by a Subterraneous Channel, with another such _Whirl-pool_
in the _Bodnick Bay_; by which commerce, according to him, the Waters,
when, upon their accumulation and crowding together in one of these places,
they are swallowed up by the Gulf there, carrying along with them
whatsoever is in the way and lodging it in a certain receptacle at the
bottom thereof, are conveyed through the same under-ground Channel to the
other Gulf; where again, upon the like flux and retumescence of Waters,
they are absorbed, and through the same Channel do reciprocally run to the
former Gulf, and meeting in their impetuous Passage with the things
formerly sunk down into the Repository, carry them aloft, with themselves;
and cast them up again on the Coast of _Norway_, p. 146.

A Relation of strange _Earth-quakes_, p. 220

{116}

An Enumeration of all the celebrated _Medical Water, and hot Baths_, in all
parts of the world, p. 236. _et seq._

In the _Second_ Part, some of his special Observations, are, How _Stones_
are _coloured_ and _figured_ under ground, p. 13. 24, 25.

Natures skill in _Painting_ of _Stones_, p. 22.

A whole Natural _Alphabet_ represented upon _Stones_, and all sorts of
_Geometrical_ Figures, naturally Imprinted upon them, p. 23.

The cause of the variety of Colours in _Prismes_, and the Authors severe
Judgment concerning those, that hold them to be meerly _Phantastical_,
_pag._ 15, 16, 17. Where he also delivers an Experiment, by him counted
wonderful, exhibiting all sorts of Colours by the means of _Mercury_,
coagulated by the vapour of Lead, and put in a Brass spoon upon burning
Coals.

The cause of the curious Colours in _Birds_, p. 17.

The way of Nature in the Generation of _Diamonds_, p. 21.

A way of preparing such a Liquor, that shall sink into, & colour the whole
Body of Marble, so that a Picture made on the surface thereof, shall, the
stone being cut through, appear also in the inmost part of the same, p. 43.

A Story of a whole Village in _Africa_ turned into Stone, with all the
people thereof, p. 50.

An Experiment, representing the Generation of the _Stone_ in the _Bladder_,
p. 52.

An _Asbestin_ Paper, that shall last perpetually, p. 74.

Several Relations of numerous Societies of People living under ground, and
their _Oeconomy_; whereof a strange one is alledged to have been found in
_England_, attested by an _English_ Author, p. 97, 98, 99.

A Relation of a Man that bred a Serpent in his Stomach, which came from him
of the length of one Foot and a half, affirmed by the Author to have been
seen by himself, p. 126.

Of whole Forrests of Coral at the bottom of the _Red Sea_, p. 159. {117}

The vanity of _Virga Divinatoria_, p. 181.

A peculiar way of washing out very small _Dust-gold_, p. 198.

Of some extraordinary big pieces of perfect _Natural_ Gold and Silver, p.
203.

Of a very rare Mineral, sent to the Author out of the _Hungarian_ Mines,
which had pure Silver branching out into Filaments, and some splendid
yellow parts, which was pure Gold, and some dark parts, which was Silver
mixed with Gold, 189.

_Salt_ the _Basis_ of all Natural Productions, and the admirable variety of
Salts, p. 299.

Strange Figures of _Plants_, p. 348.

The way of producing _Plants_; p. 414.

In how much time a Swallow can fly about the World, p. 411, &c.

This may suffice, to give occasion to the Searchers of Nature, to examine
this Book, and the Observations and Experiments contained therein, together
with the Ratiocinations raised thereupon, and to make severer and more
minute Inquiries and Discussions of all.

       *       *       *       *       *

_A farther account of an Observation above-mentioned, about _White Blood_._

Since the Printing of the former Sheet, there is this farther account from
the same hand.

Mr. _Boyle_,

I have at length, according to your desire, received from the Ingenious Dr.
_Lower_, an account in writing of the Observation about _Chyle_ found in
the Blood; which though you may think strange, agrees well with some
Experiments of his and mine, not now to be mentioned. The Relation, though
short, comprizing the main Particulats of what he had more fully told me in
Discourse, I shall give it you with little or no variation from his own
words. {118}

A Maid, after eating a good Break-fast, about seven in the Morning, was let
Blood about eleven the same day in her Foot; the first Blood was receiv'd
in a Porringer, and within a little while it turn'd very white; the last
Blood was received in a Sawcer, which turn'd white immediately, like the
white of a Custard. Within five or six hours after, he (the Physitian)
chanced to see both, and that in the Porringer was half Blood and half
Chyle, swimming upon it like a Serum as white as Milk, and that in the
Sawcer all Chyle without the least appearance of a drop of Blood; and when
he heated them distinctly over a gentle fire, they both harden'd: As the
white of an Egge when 'tis heated, or just as the _Serum_ of Blood doth
with heating, but far more white. This Maid was then in good health, and
only let Blood because she never had her Courses, yet of a very florid
clear Complexion.

       *       *       *       *       *


Note.

_The _Reader_ of these Papers is desired, that in those of _Numb. 4. pag.
60. lin. 10_. he would be pleased to read _eight_, instead of _hundred_:
this latter word having been put in by a great over-sight, and without this
Correction, injuring that Author, whose Considerations are there related.
This Advertisement should have been given in _Number 5_. but was omitted
for haste._

       *       *       *       *       *


Imprimatur _Rob. Say, Vice-Cancel._ Oxon.

Oxford, Printed by _Leonard Lichfield_: for _Richard Davis_. 1665.

{119}

       *       *       *       *       *




_Num._ 7.

PHILOSOPHICAL
_TRANSACTIONS._

       *       *       *       *       *

Monday, _Decemb._ 4. 1665.

       *       *       *       *       *

The Contents.

    _Monsieur de _Sons_ progress in working _Parabolar_ Glasses. Some
    speculations of Monsieur _Auzout_ concerning the changes, likely to be
    discovered in the Moon. The instance of the same Person to Mr. _Hook_,
    for communicating his Contrivance of making with Glasses of a few feet
    Diameter, _Telescopes_ drawing several hundred feet; together with his
    Offer of recompensing that secret with another, which teaches, How to
    measure with a _Telescope_ the _Distances of Objects_ upon the _Earth_.
    The Experiment of _Kircher_, of preparing a Liquor, that shall sink
    into, and colour the whole Body of Marble, delivered at length. An
    Intimation of a Way found in _Europe_, to make good _China-Dishes_. An
    Account of an odd Spring in _Westphalia_, together with an Information
    touching _Salt-Springs_; and a way of straining _Salt-water_. Of the
    Rise and Attempts of a way to conveigh Liquors immediately into the
    Mass of Blood._

       *       *       *       *       *

_Of Monsieur _de Sons_ Progress in working _Parabolar_ Glasses._

Since what was mentioned in the immediately precedent _Tract_, touching
Monsieur _de Son's_ noble attempt of grinding Glasses of a _Parabolical_
Figure, the _Publisher_ of these _Papers_ hath himself seen two
_Eye-glasses_ of that shape, about one inch & a half deep, and one inch and
a quarter broad, wrought by this Eminent _Artist_ with a rare
Steel-instrument of his own contrivance and workmanship, and by himself
also polished to admiration. And certainly it will be wondred at by those,
{120} who shall see these Glasses, how they could be truly wrought to such
a Figure, with such a Cavity; & yet more, when they shall hear the Author
undertake to excavate other such _Eye-Glasses_ to above two inches, and
_Object-glasses_ of five inches _Diameter_. He hath likewise already begun
his _Object-glasses_ for the mentioned two _Ocular_ ones, of the same
Figure of about two inches _Diameter_, which are to be left all open, yet
without causing any colours. Of all which 'tis hoped, that shortly a fuller
and more particular accompt will be given.

       *       *       *       *       *

_Monsieur _Auzout's_ Speculations of the Changes, likely to be discovered
in the _Earth_ and _Moon_, by their respective Inhabitants._

This Inquisitive _Philosopher_ in a letter of his, lately written to his
correspondent in _London_, takes occasion to discourse of his
considerations concerning those Changes, mentioned in the _Title_, as
followes;

I have (saith he) sometimes thought upon the _Changes_, which 'tis likely,
the supposed Inhabitants of the _Moon_ might discover in our _Earth_, to
see, whither reciprocally I could observe any such in the _Moon_. For
example, methinks, that the _Earth_ would to the people of the _Moon_
appear to have a different face in the several seasons of the year; and to
have another appearance in _Winter_, when there is almost nothing green in
a very great part of the _Earth_; when there are Countries all covered with
snow, others, all covered with water, others, all obscured with Clouds, and
that for many weeks together: _Another_ in _Spring_, when the Forrests and
Fields are green. _Another_ in _Summer_, when whole Fields are yellow &c.
Me thinks, I say, that _these_ changes are considerable enough in the force
of the reflexions of Light to be observed, since we see so many differences
of Lights in the _Moon_. We have _Rivers_ considerable enough to be seen,
and they enter far enough {121} into the Land, and have a bredth capable to
be observed. There are _Fluxes_ in certain places, that reach into large
Countries, enough to make there some apparent change; & in some of our Seas
there float sometimes such bulky masses of Ice, that are far greater, than
the Objects, which we are assured, we can see in the _Moon_. Again, we cut
down whole Forrests, and drain Marishes, of an extent large enough to cause
a notable alteration: And men have made such works, as have produced
Changes great enough to be perceived. In many places also are _Vulcans_,
that seem big enough to be distinguish't, especially in the shadow: And
when Fire lights upon Forrests of great extent, or upon Towns, it can
hardly be doubted, but these Luminous Objects would appear either in an
Ecclipse of the Earth, or when such parts of the Earth are not illuminated
by the Sun. But yet, I know no man, who hath observed such things in the
_Moon_; and one may be rationally assured that no _Vulcans_ are there, or
that none of them burn at this time. This it is (_so he goes on_) which all
Curious men, that have good _Telescopes_, ought well to attend; and I doubt
not; but, if we had a very particular _Map_ of the _Moon_, as I had
designed to make one with a _Topography_, as it were, of all the
considerable places therein, that We or our Posterity would find some
changes in Her. And if the _Mapps_ of the _Moon_ of _Hevelius_, _Divini_,
and _Riccioli_ are exact, I can say, that I have seen there some places
considerable enough, where _they_ put _parts that are clear_, whereas _I_
there see _dark ones_. 'Tis true that if there be _Seas_ in the _Moon_, it
can hardly fall out otherwise, than it doth upon our _Earth_, where
_Alluvium's_ are made in some places, and the Sea gains upon the Land in
others. _I say_, if those Spots we see in the _Moon_, are Seas, as most
believe them to be; whereas I have many reasons, that make me doubt,
whether they be so; of which I shall speak elsewhere. And I have sometimes
thought, whether it might not be, that all the Seas of the _Moon_, if there
must be Seas, were on the side of the other _Hemisphere_, and that for this
cause it might be that the _Moon_ turns not upon its _Axis_, as our
_Earth_, {122} wherein the Lands and Seas are, as it were, ballanced: That
thence also may proceed the non-appearance of any Clouds raised there, or
of any Vapors considerable enough to be seen, as there are raised upon this
Earth; and that this absence of Vapors is perhaps the cause, that no
_Crepuscle_ is there, as it seems there is none, my selfe at least not
having hitherto been able to discerne any mark thereof: For, me thinks, it
is not to be doubted, but that the reputed Citizens of the _Moon_ might see
our _Crepuscle_, since we see, that the same is without comparison
stronger, than the _Light_ afforded us by the _Moon_, even when she is
_full_; for, a little after Sun-set, when we receive no more than the
_first_ Light of the _Sun_, the sky is far clearer, than it is in the
fairest night of the _full Moon_. Mean while, since we see in _the Moon_,
when she is increasing or decreasing, the Light she receives from the
Earth, we cannot doubt, but that the People of the _Moon_ should likewise
see in the _Earth_ that Light, wherewith the _Moon_ illuminates it, with
perhaps the difference, there is betwixt their bigness. Much rather
therefore should they see the Light of the _Crepuscle_, being, as we have
said, incomparably greater. In the mean time we see not any faint Light
beyond the _Section_ of the Light, which is every where almost equaly
strong, and we there distinguish nothing at all, not so much that cleerest
part, which is called _Aristarchus_, or _Porphyrites_, as I have often
tryed; although one may there see the Light, which the _Earth_ sends
thither, which is sometimes so strong, that in the _Moon's_ decrease I have
often _distinctly_ seen _all_ the parts of the _Moon_, that were _not
enlightned_ by the _Sun_, together with the difference of the clear parts,
and the Spots, so far as to be able to discern them all. The _Shaddows_
also of all the _Cavities_ of the _Moon_ seem to be stronger, than they
would be, if there were a _Second_ Light. For, although a far off, the
shaddows of our Bodies, environed with Light, seem to Us almost dark; yet
they doe not so appear so much, as the Shaddows of the _Moon_ doe; and
those that are upon the _Edge_ of the _Section_, {123} should not appear in
the like manner. But, I will determine nothing of any of these things. When
I shall hereafter have made more frequent Observations of the Moon with my
_great Telescopes_, in convenient time, I shall then perhaps learn more of
it, than I know at present, at least it will excite the _Curious_ to
endeavor to make the like Observations; and it may be, others, that I have
not thought of.

       *       *       *       *       *

_The Instance of the _same Person_ to Mr. _Hook_, for communicating his
Contrivance of making, with a Glass of a Sphere of 20 or 40 foot
_diameter_, a _Telescope_ drawing several hundred foot; and his offer of
recompensing that Secret with another, teaching To measure with a
_Telescope_ the _Distances of Objects_ upon the Earth._

In _Numb._ 4. Of these _Papers_, pag. 67. Mr. _Hook_ had intimated, that he
would shortly discover a way of his, with a _Plane-convex_ Glasse of a
Sphære of 20. or 40. feet _Diameter_, without _Veines_, and truly wrought
of that _Figure_, to make a _Telescope_, that with a single _Eye-glass_
should draw 300, 400, yea 1000 feet, _without_ at all _altering the
Convexity_: Monsieur _Auzout_ returns this consideration, and offer upon
it, which follows:

To perform (_saith he_) with a _lesser Object-glass_ the effect of a _great
Telescope_, we must find out a way to make such an _Object-glass_ to
receive as many Rayes as one will, without their being sensibly distant
from one another; to the end, that by applying to it a _stronger
Eye-glass_, there may be still Beams enough to see the Object, and to
obliterate the small specks and imperfections of the _Eye-glass_. And if
Mr. _Hook_ hath this Invention, I esteem it one of the greatest, that can
be found in the matter of _Telescopes_. If he please to impart it to us, we
shall be obliged to him; and {124} I wish, I had a secret in _Opticks_ to
encourage him to that communication. If I did believe, that this would be
esteemed one, To measure with a _great Telescope_ the _distance of Objects_
upon the _Earth_; which I have found long since, and proposed to some by
way of Paradox; _Locorum distantias ex unica statione, absque ullo
Instrumento Mathematico, metiri_; I doe here promise to discover it to him,
with the necessary Tables, as soon as He shall have imparted his to me;
which I will use, as he shall order me. For, although the _Practise_ doe
not altogether answer the _Theory_ of my Invention, because that the length
of the _Telescopes_ admits of some Latitude; yet one comes near enough, and
perhaps as Just, as by most of the wayes, ordinarily used with Instruments.
That, which I am proposing, I doubt not but M. _Hook_ will soon understand,
and see the determination of all Cases possible. I shall only say, that if
we look upon the sole _Theory_, we make use of an ordinary _Telescope_,
whereof the _Eye-glass_ is to be _Convexe_: for, by putting the Glasses at
a little greater distance, than they are, proportionably to the distance
for which it is to serve, and by adding to it a _new Eye-glass_, the Object
will be seen distinct, though obscure; and if the _Eye-glass_ be _Convexe_,
the Object will appear erect. They may be done two manner of ways; either
by leaving the _Telescope_ in its ordinary situation, the _Object-glass_
before the _Eye-glass_; or by inverting it, and putting _this_ before
_that_. But if any will make use of two _Object-glasses_, whereof the
_Focus's_ are known, the distance of them will be known. If it be supposed,
that the _Focus_ of the _first_ be B. and _that_ of the _second_ C, and the
distance given, B + 2D, and that D _minus_ C, be _equal_ to F; for, this
distance will be _equal_ to B + C + F - rF² - C². And if you have the
_Focus_ of the _first Object-glass_, equal to B, the distance, where you
will put the _second_ Glass equal to B + C + D, the _focus_ of the 2d
Glasse will be found equal to CD/{C+D}. And if you will that the Object
shall be magnified as much with these two Glasses, as it would be with a
single one, whereof the _Focus_ {125} should be of the distance given,
having the _Focus_ of the _Object-glass_ given equal to B, and the distance
to B + D; the distance between the first and the second Glass will be equal
to {2B² + 2BD}/{2B + D}, whence subducting B (the _Focus_ of the
_Object-glass_ given) there remains BD/{2B + D}; and if this sum be
supposed equal to C, we shall easily know, by the preceding Rule, the
_Focus_ of the _second_ Glass.

So far M. _Auzout_, who, I trust, will receive due satisfaction to his
desire, as soon as the happy end of the present Contagion shall give a
beginning and life again to the Studies and Actions of our retired
_Philosophers_.

I shall onely here adde, That the Secret he mentions [_Of measuring the
distance of Places by a Telescope (fitted for that purpose) and from one
Station_] is a thing already known (if I am not mis-informed) to some
Members of our Society; who have been a good while since considering of it,
and have contrived ways for the doing of it: Whether the same with those of
Mr. _Auzout_, I know not. Nor have I (at the distance that I am now from
them) opportunity of particular Information.

       *       *       *       *       *

_An Experiment of a way of preparing a Liquor, that shall sink into, and
colour the whole Body of _Marble_, causing a _Picture_, drawn on a surface,
to appear also in the _inmost_ parts of the Stone._

This _Experiment_, having been hinted at in the next foregoing _Papers_,
out of the _Mundus Subterraneus_ of _Athanasius Kircher_, and several
Curious Persons, who either have not the leisure to read Voluminous
Authors, or are not readily skilled in that Learned Tongue wherein the said
Book is written, being very desirous to have it transferred hither, it was
thought fit to comply with their desire herein.

The Author therefore of the _Mundus_, &c, having seen {126} some stones
reputed to be _natural_ that had most lively Pictures, not only upon them,
but passing _thorow_ their whole substance, and thereupon finding an
_Artist_; skilful to perform such rare workmanship, did not only pronounce
such stones to be _artificial_, but when that _Artist_ was unwilling to
communicate unto him his Secret, did joyn his study and endeavors with
those of one _Albertus Gunter_ a _Saxon_, to find it out themselves:
wherein having succeeded, it seems, they made the Experiments which this
Industrious and communicative _Jesuit_ delivers in this manner:

The Colours, saith he, are thus prepared; I take of _Aqua fortis_ and _Aqua
Regis_, two ounces _ana_; of _Sal Armoniack_ one ounce; of the best _Spirit
of Wine_, two drachms; as much _Gold_ as can be had for nine _Julio_'s (a
_Julio_ being about six pence English) of pure _Silver_, two drachmes.
These things being provided, let the Silver, when calcined, be put into a
Vial; and having powred upon it the two drachmes of _Aqua fortis_, let it
evaporate, and you shall have a Water yielding first a _blew_ Colour, and
afterwards a _black_. Likewise put the Gold, when calcin'd, into a Vial,
and having powred the _Aqua Regis_ upon it, set it by to evaporate: then
put the _Spirit of Wine_ upon the _Sal Armoniack_, leaving it also till it
be evaporated; and you will have a Golden coloured Water, which will afford
you divers Colours. And, after this manner, you may extract many
_Tinctures_ of Colours out of other Mettals. This done, you may, by the
means of these two Waters, paint what Picture you please upon white Marble,
of the _softer_ kind, renewing the Figure every day for several days with
some fresh superadded Liquor, and you shall find in time, that the Picture
hath penetrated the _whole_ solidity of the Stone, so that cutting it into
as many parts as you will, it will always represent unto you the same
Figure on both sides.

_So far he_, which how far it answers expectation, is referred to the Tryal
of Ingenious Artists. In the mean time there are not wanting Experienced
Men that scruple the Effect, but {127} yet are far from pronouncing any
thing positively against it, so that they doe not discourage any that have
conveniencies, from trying.

But whether the way there mentioned will succeed, or not, according to
expectation: Sure it is that a Stone-cutter in _Oxford_, Mr. _Bird_, hath
many years since found out a way of doing the same thing, in effect, that
is here mentioned; and hath practised it for many years. That is, he is
able so to apply a colour to the outside of polished Marble, as that it
shall sink a considerable depth into the body of the stone; and there
represent like figures or images as those are on the outside; (deeper or
shallower according as he continues the application, a longer, or lesser
while.) Of which kind there be divers pieces to be seen in _Oxford_,
_London_, and elsewhere. And some of them being shewed to his Majesty, soon
after his happy restauration, they were broken in his presence, and found
to answer expectation. And others may be dayly seen, by any who is curious,
or desirous to see it.

       *       *       *       *       *

_An Intimation of a Way, found in _Europe_ to make _China-dishes_._

Notice was lately given by an inquisitive _Parisian_ to a friend of his in
_London_, that by an Acquaintance he had been informed, that Signor
_Septalio_, a Canon in _Millan_, had the Secret of making as good
_Porcelane_ as is made in _China_ it self, and transparent; adding that he
had seen him make some.

This as it deserves, so it will be further inquired after, if God permit.

       *       *       *       *       *

_An Account of an odd _Spring_ in _Westphalia_, together with an
Information touching _Salt-Springs_ and the straining of salt-water._

An observing Gentleman did lately write out of _Germany_, that in
_Westphalia_ in the Diocess of _Paderborn_, is a Spring, which looses it
self twice in 24 houres; coming always, after 6 houres, back again with a
great noise, and so forcibly, as {128} to drive 3 Mills not far from its
source. The Inhabitants call it the _Bolderborn_, as if you should say, the
_Boysterous Spring_.

_The same Person_, having mentioned the many _Salt-Springs_ in _Germany_,
as those at _Lunenburg_, at _Hall_ in _Saxony_, at _Saltzwedel_ in
_Brandenburger Mark_, in _Tyrol_, &c. observes, that no Salt-water, which
contains any Metal with it, can well be sodden to Salt in a Vessel of the
same Metal, which it self contains, except _Vitriol_ in Copper Vessels.

_He adds_, that, to separate Salt from Salt-water, without Fire, if you
take a Vessel of Wax, hollow within, and every where tight; and plunge it
into the Sea, or into other Salt-water, there will be made such a
separation, that the vessel shall be full of sweet water, the Salt staying
behind: but, though this water have no saltish taste, yet, _he saith_,
there will be found a Salt in the Essay, which is the Spirit of Salt,
subtile enough with the water to penetrate the Wax.

       *       *       *       *       *

_An Account of the Rise and Attempts, of a Way to conveigh Liquors
immediately into the Mass of Blood._

Whereas there have lately appeared in publick some _Books_, printed beyond
the Seas, treating of the Way of _Injecting liquors into Veines_; in which
Books the _Original_ of the _Invention_ seems to be adscribed to others,
besides him, to whom it really belongs; It will surely not be thought
amiss, if something be said, whereby the true _Inventor's_ right may beyond
exception be asserted & preserved; To which end, there will need no more,
than barely to represent the _Time_ when, and the _Place_ where, & among
whom it was first started and put to tryal. To joyn all these circumstances
together, 'Tis notorious, that at least six years since (a good while
before it was heard off, that any one did pretend to have so much as
thought of it) the Learned and Ingenious Dr. _Christopher Wren_ did propose
in the _University_ of _Oxford_ (where he now is the Worthy Savilian
Professor of _Astronomy_, and where very many Curious Persons are ready to
{129} attest this relation) to that Noble Benefactor to Experimental
Philosophy, Mr. _Robert Boyle_, Dr. _Wilkins_, and other deserving Persons,
That he thought, he could easily contrive a Way to conveigh any liquid
thing immediately into the Mass of Blood; _videl_: By making Ligatures on
the Veines, and then opening them on the side of the Ligature towards the
Heart, and by putting into them slender Syringes or Quills, fastened to
Bladders (in the manner of Clyster-pipes) containing the matter to be
injected; performing that Operation upon pretty big and lean doggs, that
the Vessels might be large enough and easily accessible.

This Proposition being made, M. _Boyle_ soon gave order for an _Apparatus_,
to put it to Experiment; wherein at several times, upon several Doggs,
_Opium_ & the Infusion of _Crocus Metallorum_ were injected into that part
of the hind-legs of those Animals, whence the larger Vessels, that carry
the Blood, are most easy to be taken hold of: whereof the success was, that
the _Opium_, being soon circulated into the Brain, did within a short time
stupify, though not kill the Dog; but a large Dose of the _Crocus
Metallorum_, made another Dog vomit up Life and all: All which is more
amply and circumstantially delivered by Mr. _Boyle_ in his Excellent Book
of the _Usefulness of Experimental Philosophy_, Part 2. Essay 2. pag. 53.
54. 55. Where 'tis also mention'd, that the fame of this Invention and of
the succeeding Tryals being spread, and particularly coming to the
knowledge of a foreign _Ambassadour_, that was Curious, and then resided in
_London_, it was by him tryed with some _Crocus Metallorum_, upon a
Malefactor, that was an inferiour Servant of his; with this success, that
the Fellow, as soon as ever the Injection began to be made, did, either
really or craftily, fall into a swoon; whereby, being unwilling to
prosecute so hazardous an Experiment, they desisted, without seeing any
other effect of it, save that it was told the Ambassadour, that it wrought
once downwards with him: Since which time, it hath been frequently
practised both in _Oxford_ & _London_; as well before the _Royal Society_,
as elsewhere. And particularly that Learned {130} Physitian, Dr. _Timothy
Clerk_, hath made it part of his business, to pursue those Experiments with
much industry, great accurateness, and considerable observations thereon;
which above two years since, were by him produced and read before the
_Royal Society_, who thereupon desired him, as one of their Members, to
compleat, what he had proposed to himself upon that subject, and then to
publish the same: the Effect whereof 'tis hoped, will now shortly appear,
and not prove unwelcome to the Curious.

Some whereof, though they may conceive, that liquors thus injected into
Veines without preparation and digestion, will make odde, commotions in the
Blood, disturb Nature, and cause strange Symptoms in the Body, yet they
have other thoughts on Liquors, that are prepared of such things, as have
passed the Digestion of the Stomach; for example, of Spirit of Urine, of
Harts-horne, of Blood &c. And they hope likewise, that besides the
_Medical_ Uses, that may be made of this _Invention_, it may also serve for
_Anatomical_ purposes, by filling, after this way, the vessels of an Animal
as full, as they can hold, and by exceedingly distending them, discover
_New_ Vessels, &c: But not now to enlarge upon the Uses, the Reader may
securely take this Narrative, as the naked real Matter of Fact, whereby
'tis as clear, as Noon day (both from the Time, and irrefragable Testimony
of very many considerable Persons in that University, who can jointly
attest it; as well as from that particular unquestionable one of Mr.
_Boyle_ and his worthy Company, who were the first Eye-witnesses of the
Tryals made,) that to _Oxford_, and in it, to Dr. _Christopher Wren_, this
Invention is due; and consequently, that all others, who discourse or write
of it, doe either derive it from Him, or are fallen upon the same Devise
several years after Him.

       *       *       *       *       *


_Published with License._

Oxford, Printed by _A: & L: Lichfield_, for _Ric: Davis_. 1665.

{131}

       *       *       *       *       *




_Num._ 8.

PHILOSOPHICAL
_TRANSACTIONS._

       *       *       *       *       *

Munday, _Januar._ 8. 1665/6.

       *       *       *       *       *

The Contents.

    _An Account of the Tryals, made in _Italy_ of _Campani's_ new Optick
    Glasses. A further relation of the Whale-fishing about the _Bermudas_,
    and upon the Coast of _New England_, and _New Netherland_. Of a
    remarkable Spring of _Paderborn_ in _Germany_. Of some other uncommon
    Springs at _Basel_ and in _Alsatia_. Of the richest Salt-springs in
    _Germany_. Some Observations of Strange Swarms of _Insects_, and the
    mischiefs done by them: as also of the Brooding of Snakes and Vipers.
    Observations of odd Constitutions of humane Bodies. Of a way, used in
    _Italy_, of preserving Ice and Snow by _Chaffe_. Directions for Sea-men
    bound for far Voyages, drawn up by Master _Rook_, late _Geometry_
    Professour of _Gresham Colledge_. Some Observations of _Jupiter_;
    Eclipsed by one of his _Satellites_: and of his Conversion about his
    _Axis_. Of some Philosophical and Curious Books, that are shortly to
    come abroad._

       *       *       *       *       *

_An Account of the Tryalls, made in _Italy_ of _Campani's_ new _Optick
Glasses_._

An Inquisitive _Parisian_ writes to his Correspondent in _London_, as
follows;

We received lately news from _Rome_, from a very Curious Person of our
acquaintance, importing, that _Campani_ hath had the advantage of _Divini_.
The Great Duke of _Toskany_, and Prince _Leopold_, his Brother, upon Tryal,
made of both their Glasses, have found those of _Campani_ excel the other,
and with them they have been able, easily to distinguish people {132} at 4
Leagues distance: Of which I intend you more particulars hereafter.

Among them are expected the _Length_ of these _Telescopes_, and the
Largeness of the _Aperture_ of their _Object-glasses_. In the mean time,
the _Parabolical-glasses_, formerly mentioned to be in hand here at
_London_, are finishing with all possible care and industry.

       *       *       *       *       *

_A Further Relation of the _Whale-fishing_ about the _Bermudas_, and on the
Coast of _New-England_ and _New-Netherland_._

The same Person, that communicated the particulars about the new
Whale-fishing near the _Bermudas_, mentioned in the first of these
_Tracts_, gives this further Information; That there have been since taken
by order of the _Bermudas_ Company, sixteen of those Whales, the Oyle
whereof, to the quantity of 50 or 60 Tuns arrived in _Ireland_ at
_Limrick_, some few months agoe.

He adds, that about two years since, there stranded upon the Coast of
_New-England_ a dead Whale, of that sort, which they call _Trumpo_, having
Teeth resembling those of a Mill, and its mouth at a good distance from,
and under the Nose or Trunk, and several boxes or partitions in the Nose,
like those of the Tailes in Lobsters; and that that being open'd there run
out of it a thin oily substance, which would candy in time; after which,
the remainder, being a thick fatty substance, was taken out of the same
part, with a scoope. And this substance he affirmed to be the _Sperma
Ceti_; adding further, that the _Blubber_, as they call it, it self, of the
same sort of Whales, when stewed, yields on the top a creamy substance,
which taken off, and thrown upon white wine, lets fall a dirty
heterogeneous sediment, but what remains aloft, affords a
_Sperma-Ceti_-like matter. {133}

He concluded his relation with observing, that these whales were to be met
with, between the Coast of _New-England_, and _New-Netherland_, where they
might be caught eight or nine months in the year, whereas those about the
_Bermudas_ are to be found there only in the Months of _February_, _March_
and _April_.

Concerning the death of the Whale, which hath been related to have stranded
upon _New-England_, it is not very improbable, but, (that Fish having also
more than one Enemy, whereof a small Fish called the _Thresher_ is one,
who, by Mr. _Terry's_ Relation in his _East-Indian_ Voyage, with his
nimbleness vexes him as much, as a Bee does a great Beast on the land; and
a certain horny Fish another, who runs its horn into the Whal's belly) it
may have been kill'd by the latter of these two; which kind of Fish is
known, sometimes to run its horn into Ships (perhaps taking them for
Whales) and there snapping it asunder; as hapned not long since to an
English Vessel in the _West-Indian_ Seas; the broken piece of that Horn
being by the Master of that ship presented to the King, and now kept in His
Majesties Repository: the like whereof befel a _French_ Vessel, sailing
towards the _East-Indies_, according to the Relation, made by Monsieur
_Thevenot_ in his second _Tome_ of _Curious Voyages_.

       *       *       *       *       *

_Of a remarkable Spring, about _Paderborn_ in _Germany_._

An inquiring Gentleman of those parts writes to his Friend in _London_, as
follows;

In this Diocess of _Paderborn_, about 2 leagues from that Town, is a treble
Spring call'd _Metborn_, which has three streams, two wherof are not above
one foot and a half distant from one another, and yet of so differing
qualities, that whereas one of them is limpid, blewish, lukewarm, bubling,
and holding Sal-armoniack, Ochra, Iron, Vitriol, {134} Allum, Sulphur,
Niter, Orpiment, used against Epilepsie, bad Spleens, and the Wormes; the
other is Ice-cold, turbid and whitish, much stronger in tast, and heavier
than the former, holding much Orpiment, Salt, Iron, Niter, and some
Sal-Armoniack, Allum and Vitriol; Of this all Birds, observed to drink of
it, doe dye; which I have also privately experimented by taking some of it
home, and giving it to Hens, after I had given them Oates, Barly and
Bread-crums; For, soon after they had drunk of it, they became giddy,
reeled, and tumbled upon their backs, with convulsion-fitts, and so dyed
with a great extention of their leggs. Giving them common-salt immediatly
after they had drunk; they dyed not so soon; giving them vineger, they dyed
not at all, but seven or eight days after were troubled with the _Pipp_.
Those that dyed, being open'd, their Lungs were found quite shrivelled
together. Yet some men, that are troubled with Worms, taking a litle
quantity of it, and diluting it in common water, have been observed by this
means to kill the Worms in their bellies, so that a great number of worms
come from them; whereupon though they are sick, yet they dye not. As to the
third stream, that lyes lower than the other two, about 20 paces distant
from them, it is of a greenish colour, very clear, and of a sowre sweet
tast, pleasing enough. It hath about a middle weight between the other two;
whence wee guess, that it is mixed of them both, meeting there together: to
confirm which, we have mixed equal quantities, of those two, with an
addition of a litle common well-water, and have found that they, being
stirred together and permitted to setle, made just a water of the same
colour and tast of this third stream.

       *       *       *       *       *

_Of some other not-common Springs at _Basel_ and in _Alsatia_._

A Curious Person writes from those Places in manner following; {135}

At _Basel_ the Spring, running in the _Gerbergasse_ (or _Tanners-street_)
from St. _Leonard's_ Hill, is of a Blewish colour, and somewhat troubled,
holding Copper, Bitumen, and Antimony, about 3 parts of the first, one of
the second, and two of the last, as has been examined by skilful Persons.
Our Tanners do water their Skins in it; and being a well-tasted and
wholesome Water, it is both much drunk, and used to Bath in. It mingles
with another Spring water, call'd the _Birsick_, and with it, between the
_Salt-tower_ and the _Rhine-gate_ runs into the _Rhine_.

In the same Town (which abounds with Spring-waters) there are two, among
the rest, called _Bandulph's-well_, and _Brun Zum Brunnen_, that are more
observable then the other; the former of them having a _Camphory_ and
drying Quality, and used against Hydropical Distempers; the latter
containing some Sulphur, Saltpeter and Gold, and being an excellent Water
to drink, much used in the principal Tavern of the City, where the chief of
the Town do resort, and near which it runs.

In _Alsatia_ in the Valley, called _Leberthal_, near _Geesbach_ (an ancient
Mine-work) there runs out of a _Cavern_ a foul, fattish, oily Liquor,
which, though the Country-men of that place employ to the vile use of
greasing their Wheels, instead of ordinary Wheel-grease; yet doth it afford
an excellent Balsom, by taking a quantity of it, and putting it in an
Earthen Pot well luted, that no steam may exhale; and then with a gentle
Fire at first, but a stronger afterwards, boyling it for three hours
together; in which space it will boyl in a fourth part, and an Earthen
Matter, like Pitch, will settle it self at the bottom: but on the top
thereof, when cold, there will swim a fatty Substance, like Lyne-Oyl,
limped and somewhat yellowish, which is to be decanted from the thick
Sediment, and then gently distilled in an Alembick in _Arena_, by which
means, there will come over two differing Liquors, one Phlegmatick, the
other Oily, {136} which latter swimming on the Phlegm, is to be severed
from it. The Phlegm is used as an excellent Resister and Curer of all the
Putrefactions of the Lungs and Liver, and it heals all foul Wounds and
Ulcers. The Oily part, being diluted with double its quantity of distilled
Vineger, and brought three times over the Helm, yields a rare Balsom,
against all inward and outward Corruptions, stinking Ulcers, hereditary
Scurfs and Scabs: 'Tis also much used against Apoplexies, Palsies,
Consumptions, Giddinesses, and Head-aches. Inwardly they take it with
Succory-water against all corruptions of the Lungs. It is a kind of
_Petroleum_, and contains no other Mineral Juice, but that of _Sulphur_,
which seems to be thus distilled by _Nature_ under ground; the distillation
of an Oyl out of _Sulphur_ by Art, being not so easie to perform.

       *       *       *       *       *

_Of the richest _Salt-Springs_ in _Germany_._

An Account having been desired of those two chief _Salt-Springs_ in
_Germany_, at _Hall_ and _Lunenburg_, it was lately transmitted thus:

The _Salt-Springs_ at _Hall_ in _Saxony_ are four, called _Gutiaar_, the
_Dutch-Spring_, the _Mettritz_, and the _Hackel-dorn_; whereof the three
first hold near the same proportion of Salt; the last hold less, but yields
the purest Salt. The three first hold about seven parts of Salt, three of
Marcasit, and fourteen of water: They are, besides their Oeconomical use,
employed Medicinally to Bath in, and to draw a Spirit out of it, exhibited
with good success against Venom, and the putrefaction of the Lungs, Liver,
Reins, and the Spleen.

The _Salt Water_ at _Lunenburgh_, being more greenish then white, and not
very transparent, is about the same nature and hold with that of _Hall_. It
hath a mixture of Lead with it, whence also it will not be sod in Leaden
Pans, and if it held no Lead at all, it would not be so good, that Metal
being judged to _purifie_ the Water: whence also the Salt of {137}
_Lunenburg_ is preferred before all others, that are made of Salt Springs.

       *       *       *       *       *

_Some Observations of swarms of strange Insects, and the Mischiefs done by
them._

A great Observer, who hath lived long in _New England_, did upon occasion,
relate to a Friend of his in _London_, where he lately was, That some few
Years since there was such a swarm of a certain sort of Insects in that
_English_ Colony, that for the space of of 200 Miles they poyson'd and
destroyed all the Trees of that Country; there being found innumerable
little holes in the ground, out of which those Insects broke forth in the
form of _Maggots_, which turned into _Flyes_ that had a kind of taile or
sting, which they struck into the Tree, and thereby envenomed and killed
it.

The like Plague is said to happen frequently in the Country of the
_Cosacks_ or _Ukrani_, where in dry Summers they are infested with such
swarms of _Locusts_, driven thither by an _East_, or _South-East_ Wind,
that they darken the Air in the fairest weather, and devour all the Corn of
that Country; laying their Eggs in _Autumn_, and then dying; but the Eggs,
of which every one layeth two or three hundred, hatching the next Spring,
produce again such a number of Locusts, that then they do far more mischief
than afore, unless Rains do fall, which kill both Eggs and the Insects
themselves, or unless a strong _North_ or _North-West_ Wind arise, which
drives them into the _Euxin_ Sea: The Hogs of that Country loving these
Eggs, devour also great quantities of them, and thereby help to purge the
Land of them; which is often so molested by this Vermine, that they enter
into their Houses and Beds, fall upon their Tables and into their Meat,
insomuch that they can hardly eat without taking down some of them; in the
Night when they repose themselves upon the ground, they cover it three, or
four Inches thick, and if a Wheel pass {138} over them, they emit a stench
hardly to be endured: All which, and much more may be fully seen in the
_French_ Description of the Countries of _Poland_, made by _Monsieur de
Beauplan_, and by _Monsieur Thevenot_, in his Relation of the _Cosacks_,
contained in the First part of his _Curious Voyages_.

       *       *       *       *       *

_An Observation touching the Bodies of Snakes and Vipers._

Several have taken notice, that there is a difference between the brooding
of Snakes and Vipers, those laying their Eggs in Dung-hills, by whose
warmth they are hatched; but these (Vipers) brooding their Eggs within
their Bellies, and bringing forth live Vipers. To which may be added, That
some affirm to have seen Snakes lye upon their Eggs, as Hens sit upon
theirs.

       *       *       *       *       *

_Some Observations of odde Constitutions of Bodies._

A very curious Person, studying Physick at _Leyden_, to whom had been
imparted those Relations about a Milky Substance in Veins, heretofore
alledged in _Numb._ 6. returns, by way of gratitude, the following
Observations.

There was (saith he) not many Years since, in this Country a Student, who
being much addicted to the study of _Astronomy_, and spending very many
Nights in Star-gazing, had, by the Nocturnal wet and cold temper of the
Air, in such a manner obstructed the pores of his skin, that little or
nothing exhaled from his Body; which appeared hence, because that the
shirt, he had worn five or six weeks, was then as white as if he had worn
it but one day. In the mean while he gathered a subcutaneous Water, of
which yet he was afterwards well cured.

We have also (_saith the same_) seen here a young Maid, of about thirteen
Years of age, which from the time that she was but six Years old, and began
to be about her Mother in {139} the Kitchin, would, as often as she was bid
to bring her Salt, or could else come at it, fill her Pockets therewith,
and eat it, as other children doe Sugar: whence she was so dried up, and
grown so stiff, that she could not stirre her limbs, and was thereby
starved to death.

That Learned and Observing Doctor _John Beal_, upon the perusal of the
forementioned _Numb._ 6. was pleased to communicate this Note:

To your Observation, of Milk in Veines, I can add a _Phænomenon_ of some
resemblance to it, which I received above 20 years agoe from _Thomas Day_,
an Apothecary in _Cambridg_; _vid._ That himself let a man bloud in the
arme, by order of Doctor _Eade_, a Physitian there. The mans bloud was
white as Milk, as it run out of his arme, it had a little dilute redness,
but immediately, as it fell into the Vessel, it was presently white; and it
continued like drops of Milk on the pavement, where ever it fell. The
conjecture which the said Physitian had of the cause of this appearance,
was, that the Patient had much fed on Fish; affirming withall, that he had
soon been a Leper, if not prevented by Physick.

       *       *       *       *       *

_A way of preserving Ice and Snow by Chaffe._

The Ingenious Mr. _William Ball_ did communicate the relation hereof, as he
had received it from his Brother, now residing at _Livorne_, as follows;

The Snow, or Ice-houses are here commonly built on the side of a steep
hill, being only a deep hole in the ground, by which meanes, they easily
make a passage out from the bottom of it, to carry away all the water,
which, if it should remain stagnating therein, would melt the Ice and Snow:
but they thatch it with straw, in the shape of a Saucepan-cover, that the
rain may not come at it. The sides (supposing it dry) they line not with
any thing, as is done in St. _Jeames_'s Park, by reason of the moistness of
the ground. This Pit they fill {140} full of Snow or Ice (taking care that
the Ice be made of the purest water, because they put it into their wine)
over-spreading first the bottom very well with _Chaffe_; by which I mean
not any part of the straw, but what remains upon the winnowing of the Corn;
and I think, they here use Barley-chaffe. This done, they further, as they
put in the Ice, or the Snow, (which latter they ram down,) line it thick by
the sides with such Chaffe, and afterwards cover it well with the same; and
in half a years lying so, 'tis found not to want above an eight part of
what it weighed, when first put in. When ever they take it out into the
Aire, they wrap it in this Chaffe, and it keeps to admiration. The use of
it in _England_ would not be so much for cooling of drinks, as 'tis here
generally used; but for cooling of fruits, sweetmeats &c. _So far this
Author._

The other usual way both in _Italy_ and other Countries, to conserve Snow
and Ice with _Straw_ or _Reed_, is set down so punctually by Mr. _Boyle_ in
his _Experimental History of Cold_, pag. 408. 409. that nothing is to be
added. It seems _Pliny_ could not pass by these _Conservatories_, and the
cooling of drinks with Ice, without passing this severe, though elegant and
witty, Animadversion upon them: _Hi Nives, illi glaciem potant, poenásque
montium in voluptatem gulæ vertunt: Servatur algor æstibus, excogitatúrque
ut alienis mensibus nix algeat_, lib. 19. cap. 4. But the _Epigrammatist_
sports with it thus;

  _Non potare nivem, sed aquam potare rigentem_
  _De nive, commenta est ingeniosa sitis._ Martial. 14. _Ep._ 117.

       *       *       *       *       *

_Directions for Sea-men, bound for far Voyages._

It being the Design of the _R. Society_, for the better attaining the End
of their Institution, to study _Nature_ rather than _Books_, and from the
Observations, made of the _Phænomena_ and Effects she presents, to compose
such a {141} History of Her, as may hereafter serve to build a Solid and
Useful Philosophy upon; They have from time to time given order to several
of their Members to draw up both _Inquiries_ of things Observable in
forrain Countries, and _Directions_ for the Particulars, they desire
chiefly to be informed about. And considering with themselves, how much
they may increase their _Philosophical_ stock by the advantage, which
_England_ injoyes of making Voyages into all parts of the World, they
formerly appointed that Eminent Mathematician and Philosopher Master
_Rooke_, one of their Fellowes, and _Geometry_ Professor of _Gresham
Colledge_ (now deceased to the great detriment of the Common-wealth of
Learning) to think upon and set down some _Directions_ for _Sea-men_ going
into the _East_ & _West-Indies_, the better to capacitate them for making
such observations abroad, as may be pertinent and suitable for their
purpose; of which the said Sea-men should be desired to keep an exact
_Diary_, delivering at their return a fair Copy thereof to the _Lord High
Admiral_ of _England_, his Royal Highness the _Duke_ of _York_, and another
to _Trinity-house_ to be perused by the _R. Society_. Which _Catalogue_ of
_Directions_ having been drawn up accordingly by the said Mr. _Rook_, and
by him presented to those, who appointed him to expedite such an one, it
was thought not to be unseasonable at this time to make it publique, the
more conveniently to furnish Navigators with Copies thereof. They are such,
as follow;

1. To observe the Declination of the _Compass_, or its Variation from the
_Meridian_ of the place, frequently; marking withal, the _Latitude_ and
_Longitude_ of the place, wherever such Observation is made, as exactly as
may be, and setting down the _Method_, by which they made them.

2. To carry _Dipping Needles_ with them, and observe the Inclination of the
Needle in like manner.

3. To remark carefully the Ebbings and Flowings of the Sea, in as many
places as they can, together with all the Accidents, {142} Ordinary and
Extraordinary, of the Tides; as, their precise time of Ebbing and Flowing
in Rivers, at _Promontories_ or _Capes_; which way their Current runs, what
Perpendicular distance there is between the highest Tide and lowest Ebb,
during the Spring-Tides and Neap-Tides; what day of the _Moons_ age, and at
times of the year, the highest and lowest Tides fall out: And all other
considerable Accidents, they can observe in the Tides, cheifly neer Ports,
and about Ilands, as in St. _Helena_'s Iland, and the three Rivers there,
at the _Bermodas_ &c.

4. To make Plotts and Draughts of prospect of Coasts, Promontories, Islands
and Ports, marking the Bearings and Distances, as neer as they can.

5. To sound and marke the Depths of Coasts and Ports, and such other places
nere the shoar, as they shall think fit.

6. To take notice of the Nature of the Ground at the bottom of the Sea, in
all Soundings, whether it be Clay, Sand, Rock, &c.

7. To keep a Register of all changes of Wind and Weather at all houres, by
night and by day, shewing the point the Wind blows from, whether strong or
weak: The Rains, Hail, Snow and the like, the precise times of their
beginnings and continuance, especiall _Hurricans_ and _Spouts_; but above
all to take exact care to observe the _Trade-Winds_, about what degree of
_Latitude_ and _Longitude_ they first begin, _where_ and _when_ they cease,
or change, or grow stronger or weaker, and how much; as near and exact as
may be.

8. To observe and record all Extraordinary _Meteors_, Lightnings, Thunders,
_Ignes fatui_, Comets, &c. marking still the places and times of their
appearing, continuance. &c.

9. To carry with them good Scales, and Glasse-Violls of a pint or so, with
very narrow mouths, which are to be fill'd with Sea-water in different
degrees of _Latitude_, as often as {143} they please, and the weight of the
Vial full of water taken exactly at every time, and recorded, marking
withall the degree of _Latitude_, and the day of the Month: And that as
well of water near the Top; as at a greater Depth.

       *       *       *       *       *

_Some Observations concerning _Jupiter_. Of the shadow of one of his
_Satellites_ seen, by a Telescope passing over the Body of _Jupiter_._

I have received an Account from very good hands, That on the 26^{th.} of
_September_ last, at half hour after seven of the Clock, was seen, both in
_Holland_ and in _France_ (by curious Observers, with very good Telescopes)
the shadow of one of the _Satellites_ of _Jupiter_, passing over his Body.
One of those small Stars moving about his Body (which are therefore called
his _Satellites_) coming between the Sun and it, made a small Eclipse,
appearing in the Face of _Jupiter_ as a little round black Spot. The
Particulars of those Observations, when they shall come to our Hands, we
may (if need be) make them publik: Which Observations, as they are in
themselves very remarkable, and argue the Excellency of the Glasses by
which they were discovered; So are we, in part, beholding to Monsieur
_Cassini_ for them, who giving notice before hand of such Appearances to be
expected, gave occasion to those Curious Observers to look for them.

       *       *       *       *       *

_Of a permanent Spot in _Jupiter_: by which is manifested the conversion of
_Jupiter_ about his own Axis._

Besides that Transient Shadow last mentioned, there hath been observed, by
Monsieur _Cassini_, a permanent Spot in the Disque of _Jupiter_; by the
help whereof, he hath been able to observe, not onely that _Jupiter_ turns
about upon his own Axis, but also the Time of such conversion; which he
{144} estimates to be, 9 hours and 56 minutes.

For as _Kepler_ did before conjecture, from the motion of the Primitive
Planets about the Sun as their Center, that the Sun moved about its own
Axis, but could not prove it, till by _Galileo_ and _Shiner_ the Spots in
the Sun were discovered; so it hath been thought reasonable, from the
Secundary Planets moving about _Jupiter_, that _Jupiter_ is also moved
about his Axis; yet, till now, it hath not been evinced by Observation,
That it doth so move; much less, in what Period of Time. And the like
reason there is to judge so of _Saturn_, because of the Secundary Planet
discovered by Monsieur _Hugens de Zulichem_ to move about it; (though such
motion be not yet evinced from Observation:) as well as that of the
_Earth_, from its Attendant the _Moon_.

Whether the same may be also concluded of the other Planets, _Mars_,
_Venus_, and _Mercury_, (about whom have not yet been observed any
Secondary Planets to move,) is not so evident. Yet there may be somewhat of
like probability in those. Not onely, because it is possible they may have
Secundary Planets about them, though not yet discovered; (For, we know, it
was long after those of _Jupiter_, before that about _Saturn_ was
discovered; and who knows, what after times may discover about the rest?)
But because the Primary Planets being all in like manner inlightned by the
Sun, and (in all likely hood) moved by it; it is likely that they be moved
by the same Laws and Methods; and therefore, turn'd about their own Axis,
as it is manifest that some of them are.

But, as for the Secundary Planets, as well those about _Jupiter_, as that
about _Saturn_; it is most likely that they have no such Rotation upon
their Axis. Not so much because, by reason of their smalness, no such thing
hath been yet observed, (or, indeed, could be, though it were true;) But
because they being Analogical to our _Moon_, it is most likely that they
are moved in like manner. Now, though it be {145} true, that there is some
kind of _Libration_ of the Moon's body, so that we have not precisely just
the same part of it looking towards us; (as is evident by _Hevelius_
observations, and others;) yet is there no Revolution upon its Axis; the
same part of it, with very little alteration, always respecting us, as is
to be seen in _Hevelius_ his Tratise _de Motu Lunæ Libratorio_, and indeed,
by all those who have written particularly of the spots on the Moon; and is
universally known to all that have with any curiosity viewed it with
Telescopes.

       *       *       *       *       *

_Of some Philosophical and curious Books, that are shortly to come abroad._

1. Of the _Origine_ of _Forms_ and _Qualities_, deduced from _Mechanical_
Principles; by the Honorable _Robert Boyle_ Esq.

2. _Hydrostatical Paradoxes_, by the same. Both in _English_.

3. A Tract of the _Origine_ of the _Nile_, by Monsieur _Isaac Vossius_,
opposed to that of Monsieur _de la Chambre_, who is maintaining, That
_Niter_ is the principal cause of the Inundation of that River.

4. A Dissertation of _Vipers_, by _Signor Redi_, an _Italian_.

5. A Discourse of the _Anatomy_ of _a Lyon_, by the same.

6. Another, _De Figuris Salium_, by the same.

7. A Narration of the Establishment of the _Lyncei_, an _Italian_ Academy,
and of their Design and Statutes: the Prince _Cesi_ being the Head of them,
who did also intend to establish such Philosophical Societies in all parts
of the World, and particularly in _Africa_ and _America_, to be by that
means well informed of what considerable productions of Nature were to be
found in those parts. The Author yet _Anonymus_.

8. To these I shall add, a Book newly Printed in _Oxford_ (and not yet
dispersed) being, _A Catalogue of Fixed Stars_ with their _Longitudes,
Latitudes, and Magnitudes_, according to the _Observations_ of _Uleg-Beig_
(a King, and famous Astronomer, who was _Great-Grand-childe_ to the famous
{146} _Tamerlane_, and one of his Successors in some of his Kingdoms) made
at _Samarcand_, his cheief seat, (for the year of the Hegira 841, for the
year of Christ 1427), who not finding the _Tables_ of _Ptolemy_ to agree
sufficiently with the Heavens, did with great diligence, and expense, make
observations anew; as _Tycho Brahe_ hath since done. It is a small part of
a larger _Astronomical Treatise_ of his, whereof there be divers _Persian_
Manuscript Copies in _Oxford_. Out of which this is Translated and
Published, both in _Persian_ and _Latine_, by Mr. _Thomas Hyde_, now
Library Keeper to the _Bodleyan_ Library in _Oxford_: (with Commentaries of
his annexed:) Like as another part of it hath formerly been by Mr. _John
Graves_. And it were a desirable work that the whole were Translated, that
we might be the better acquainted with what was the Eastern Astronomy at
that time.

       *       *       *       *       *


_Published with License._

Oxford, Printed by _A: & L: Lichfield_, for _Ric: Davis_. 1666.

{147}

       *       *       *       *       *




_Num._ 9.

PHILOSOPHICAL
_TRANSACTIONS._

       *       *       *       *       *

_Munday_, _Feb._ 12. 1665/6.

       *       *       *       *       *

The Contents.

    _An _Apendix_ to the _Directions_ for Seamen, bound for far voyages. Of
    the judgment of some of the _English_ Astronomers, touching the
    difference between two learned men, about an Observation made of the
    first of the two late _Comets_. Of a _Correspondency_, to be procured,
    for the finding out of the _True_ distance of the _Sun_ and _Moon_ from
    the Earth. Of an Observation not long since made in _England_ of
    _Saturn_. An Account of some _Mercurial_ Observations, made with a
    _Barometer_, and their Results. Some Observations of _Vipers_, made by
    an _Italian_ Philosopher._

       *       *       *       *       *

_An _Appendix_ to the _Directions_ for Seamen, bound for far Voyages._

Whereas it may be of good use, both _Naval_ and _Philosophical_, to know,
both how to sound depths of the sea _without a Line_, and to fetch up water
from any depth of the same; the following waies have been contrived by Mr.
_Hook_ to perform both; (which should have been added to the lately printed
_Directions for Seamen_, if then it could have been conveniently done.)
{148}

[Illustration]

_First_, for the sounding of depths without a Cord, consider _Figure_ 1,
and accordingly take a Globe of _Firr_, or _Maple_, or other light Wood, as
A: let it be well secured by Vernish, Pitch, or otherwise, from imbibing
water; then take a piece of Lead or Stone, D, considerably heavier then
will sink the Globe: let there be a long Wire-staple B, in the Ball A, and
a springing Wire C, with a bended end F, and into the said staple, press in
with your fingers the springing Wire on the bended end: and on it hang the
weight D, by its ring E, and so let Globe and all sink gently into the
water, in the posture represented in the first _Figure_, to the bottom,
where the weight D touching first, is thereby stopt; but the Ball, being by
the _Impetus_, it acquired in descending, carried downwards a little after
the weight is stopt, suffers the springing wire to fly back, and thereby
sets it self at liberty to reascend. And, by observing the time of the
Ball's stay under water (which may be done by a Watch, having minuts and
seconds, or by a good Minut-glass, or best of all, by a Pendulum vibrating
seconds) you will by this way, with the help of some _Tables_, come to know
any depth of the sea.

Note, that care must be had of proportioning the weight and shape of the
Lead, to the bulk, weight, and figure of the Globe, after such a manner, as
upon experience shall be found most convenient.

In some of the Tryals already made with this Instrument, the Globe being of
Maple-wood, well covered with Pitch to hinder soaking in, was 5-13/16
inches in diameter, and weighed 2½ pounds: the Lead of 4½ pounds weight,
was of a _Conical_ figure, 11. inches long, with the sharper end downwards,
1-9/16 inches at the top, and 1/16 at the bottom in diameter. And in those
Experiments, made in the _Thames_, in the depth of 19. foot water, there
passed between the Immersion and Emersion of the Globe, 6. seconds of an
hour; and in the depth of 10. foot water, there passed 3½ seconds or
thereabout: From many of which kind of Experiments it will likely not be
hard to finde {149} out a method to calculate, what depth is to be
concluded from any other time of the like Globes stay under water.

[Illustration]

In the same Tryals, made with this Instrument in the said River of
_Thames_, it has been found, that there is no difference in time, between
the submersions of the Ball at the greatest depth, when it rose two
Wherries length from the place where it was let fall (being carried by the
Current of the _Tide_) and when it rose within a yard or so of the same
place where it was let down.

The _other_ Instrument, for Fetching up water from the depth of the sea, is
(as appears by _Figure_ 2.) a square woodden _Bucket_ C, whose bottoms
_EE_, are so contrived, that as the weight A, sinks the Iron B, (to which
the Bucket C, is fastned by two handles DD, on the ends of which are the
moveable bottoms or Valves EE,) and thereby draws down the Bucket, the
resistance of the water keeps up the Bucket in the posture C; whereby the
water hath, all the while it is descending, a clear passage through;
whereas, as soon as the Bucket is pulled upwards by the Line F, the
resistance of the water to that motion beats the Bucket downward, and keeps
it in the posture G, whereby the Included water is preserved from getting
out, and the Ambient water kept from getting in.

By the advantage of which Vessel, it may be known, whether sea water be
Salter at and towards the bottom, then at or near the top: Likewise,
whether in some places of the sea, any sweet water is to be found at the
bottom; the _Affirmative_ whereof is to be met with in the _East Indian_
Voyages of the industrious _John Hugh Van Linsckoten_, who page 16 of that
Book, as 'tis _Englished_, records, that in the _Persian Gulph_, about the
Island _Barem_, or _Baharem_, they fetch up with certain Vessels (which he
describes not) water out of the sea, from under the salt-water, four or
five fathom deep, as sweet, as any Fountain water. {150}

       *       *       *       *       *

_Of the Judgement of some of the _English_ Astronomers, touching the
difference between two learned men, about an Observation made of the First
of the two late _Comets_._

[Sidenote: _By _Telescopical_ Stars are understood such, as are not seen,
but by the help of a Telescope._]

Whereas notice has been taken in _Num._ 6. of these _Transactions_, that
there was some difference between those two deservedly celebrated
Philosophers, _Monsieur Hevelius_ and _Monsieur Auzout_, concerning an
Observation, made by the former of them, on the 8/18 of _February_ 1665. &
that thereupon some Eminent _English_ Astronomers, considering the
importance of the dispute, had undertaken the examination thereof; it will,
'tis conceived, not be unacceptable to such, as saw those Papers, to be
informed, what has been done and discerned by them in that matter. They
having therefore compared the Printed Writings of the two Dissenters, and
withall consulted the observations made with _Telescopes_ at home, by some
of the most intelligent Astronomers amongst them, who have attentively
observed the Position of that _Comet_ to the _Telescopical_ stars, that lay
in its way; Do thereupon Joyntly conclude, that, whatever that Appearance
was, which was seen near the _First Star_ of _Aries_, by _Monsieur
Hevelius_ (the truth of whose relation concerning the same, they do in no
wise question) the said _Comet_ did not come neer that _Star_ in the left
_Ear_ of _Aries_, where the said M. _Hevelius_ supposes it to have passed,
but took its course neer the _Bright Star_ in its _Left Horn_, according to
_Bayers_ Tables. And since that the Observations of judicious both _French,
Italian, & Dutch_ Astronomers (as many of them, as are come to the
knowledge of the _English_) do in the main fully agree with theirs, they do
not at all doubt, but that, there being such an unanimous {151} consent in
what has been just now declared, & the Controversie being about _Matter of
fact_, wherein Authority, Number, and Reputation must cast the Ballance,
Mons. _Hevelius_, who is as well known for his Ingenuity, as Learning, will
joyn and acquiesce in that sentiment.

       *       *       *       *       *

_Of a correspondency, to be procured, for the Finding out the _True_
distance of the _Sun_ and _Moon_ from the Earth, by the _Paralax_, observed
under (or neer) the same _Meridian_._

Seeing that the knowledge of this distance may prove of important Use, for
the Perfecting of Astronomy, and for the better establishing the doctrine
of _Refractions_, it is in the thoughts of some very curious Persons in
_England_, for the finding out the same, to settle a Correspondency with
some others abroad, that are understanding in Astronomical matters, and
live in places farr distant in _Latitude_, and under (or near) the same
_Meridian_.

To perform which, the following Method is proposed to be observed; _viz._
That at certain times agreed on by two Observatours, making use of
_Telescopes_, large, good and well fitted for this purpose, by a measuring
rod, placed within the Eye glass at a convenient distance, that it may be
distinctly seen, and serve for measuring small distances by minuts and
seconds (which is easie enough in large _Telescopes_) that, I say, each of
such observers, thus furnish't shall observe the visible way of the _Moon_
among the _Fixt Stars_, (by taking her exact distance from any _Fixt
Starr_, that lyes in or very near her way, together with the exact time of
her so appearing) and the then apparent Diameter of her Disk; continuing
these Observations every time for two or three hours; that so, {152} if
possible, two exact observations of her _Apparent_ place among the _Fixt
Stars_ being made, at two places thus distant in _Latitude_, and as near as
may be under the same _Meridian_, by these Observators concurring at the
same time, her true and exact distance may be hence collected, not onely
for that time, but at all other times, by any single Observator's viewing
her with a _Telescope_, and measuring exactly her _Apparent_ Diameter. It
were likewise desirable, that as often as there happens any considerable
_Eclipse_ of the _Sun_, that this also might be observed by them, noting
therein the exact measure of the greatest Obscuration compared with the
then _Apparent_ Diameter of his Disk. For by this means, after the distance
of the _Moon_ hath been exactly found, the distance of the _Sun_ will
easily be deduced.

As for the time, fittest for making Observations of the _Moon_, that will
be, when she is about a Quarter or somewhat less illuminated, because then
her light is not so bright, but that with a good _Telescope_ she may be
observ'd to pass close by, and sometimes over several _Fixt Stars_; which
is about four or five days before or after her Change: Or else at any other
time, when the _Moon_ passes near or over some of the bigger sort of _Fixt
Stars_, such as of the first or second _Magnitude_; which may be easily
calculated and foreseen: Or best of all, when there is any _Totall Eclipse_
of the _Moon_; for then the smallest _Telescopical Stars_ may be seen close
adjoyning to the very body of the _Moon_. Of all which particulars the two
Correspondents are to agree, as soon as he, that is to joyn abroad, shall
be found out; whereupon they are mutually to communicate to each other,
what they shall have thus observed in each place.

       *       *       *       *       *

_Of an Observation, not long since made in _England_, of _Saturn_._

[Illustration]

This Observation was made by Mr. _William Ball_, {153} accompanied by his
brother, Dr. _Ball_, _October_ 13. 1665. at six of the Clock, at _Mainhead_
near _Exeter_ in _Devonshire_, with a very good _Telescope_ near 38 foot
long, and a double Eye-glass, as the observer himself takes notice, adding,
that he never saw that _Planet_ more distinct. The observation is
represented by _Figure_ 3. concerning which, the Author saith in his letter
to a friend, as follows; This appear'd to me the present figure of
_Saturn_, somewhat otherwise, than I expected, thinking it would have been
decreasing, but I found it full as ever, and a little hollow above and
below. Whereupon the Person, to whom notice was sent hereof, examining this
shape, hath by Letters desired the worthy Author of the _Systeme of this
Planet_, that he would now attentively consider the present _Figure_ of his
_Anses_ or _Ring_, to see whether the appearance be to him, as in this
_Figure_, and consequently whether he there meets with nothing, that may
make him think, that it is not _one_ body of a Circular Figure, that
embraces his _Diske_, but _two_.

And to the end that other Curious men, in other places might be engaged, to
joyn their Observations with him, to see, whether they can find the like
appearance to that, represented here, especially such Notches or
Hollownesses, as at A and B, it was thought fit to insert here the newly
related Account.

       *       *       *       *       *

_A Relation of some _Mercurial_ Observations, and their Results._

Modern _Philosophers_, to avoyd Circumlocutions, call that Instrument,
wherein a Cylinder of Quicksilver, of between 28. and 31. Inches in
Altitude, is kept suspended after the manner of the _Torricellian_
Experiment, a _Barometer_ or _Baroscope_, first made publick by that Noble
Searcher of Nature, Mr. _Boyle_, and imployed by Him and others, to detect
all the minut variations in the Pressure and weight of the Air. For the
more {154} curious and nice distinguishing of which small changes, Mr.
_Hook_ in the _Preface_ to his _Micrography_, has described such an
Instrument with a _Wheel_, contrived by himself, and, by these two last
years trials of it, constantly found most exact for that purpose: which
being so accurate, and not difficult to be made, it were desirable, that
those who have a Genius and opportunities of making Observations of this
kind, would furnish themselves with such of these Instruments, as were
exactly made and adjusted according to the Method, delivered in the newly
mentioned place.

To say something of the Observations, made by this Instrument, and withal
to excite studious _Naturalists_ to a sedulous prosecution of the same, the
_Reader_ may _first_ take notice, that the lately named Mr. _Boyle_ hath
(as himself not long since did intimate to the Author of these _Tracts_)
already made divers Observations of this kind in the year 1659. and 1660.
before any others were publick, or by him so much as heard of; though he
has hitherto forborn to divulge them, because of some other Papers (in
whose Company they were to appear) which being hindred by other studies and
employments, he hath not as yet finished.

_Next_, that, besides several others, who, since have had the curiosity of
making such observations, the Worthy and Inquisitive Dr. _John Beal_, is
doing his part with much assiduity (of which he hath by several Letters
acquainted his Friends in _London_) both by observing himself, and by
procuring many Correspondents in several places in _England_ for the same
purpose; judging it of great importance, that Observations of this kind be
made in parts somewhat distant from one another, that so from many of
those, accurately made and then compared, it may be discovered, whether the
Aire gravitates more in the parts of the Earth lying more _East_ or _West_,
_North_ or _South_? whether on such as lie neerer to the _Sea_, or further
up into the _Mainland_? in hotter or colder weather? whether in {155} high
Winds or Calms? whether in wet weather or dry? whether most when a North,
or when a South, when an East or a West wind blows? and whether it keeps
the same seasons of Changes? and whether the seasons and changes of the Air
and Weather can be thereby discover'd, and the now hidden causes of many
other _Phænomena_ detected?

The said _Doctor_ is so much pleased with the discovery already made by the
help of this Instrument, that he thinks it to be one of the most wonderful
that ever was in the World, if we speak of strangeness, and just wonder,
and of Philosophical importance, separate from the interest of lucre. For
(_saith he in one of his Letters_) who could ever expect, that we men
should find an Art, to weigh all the Air that hangs over our heads, in all
the changes of it, and, as it were, to weigh, and to distinguish by weight,
the Winds and the Clouds? Or, who did believe, that by palpable evidence we
should be able to prove, the _serenest_ Air to be most heavy, and the
_thickest_ Air, and when darkest Clouds hang neerest to us, ready to
dissolve, or dropping, _then_ to be lightest. And though (_so he goes on_)
we cannot yet reach to all the Uses and Applications of it, yet we should
be entertain'd for a while, by the truly Honourable Mr. _Boyle_, as the
leading person herein, upon the delight and wonder. The _Magnet_ was known
many hundreds of years before it was applied to find out _New Worlds_. To
me (_saith he_) tis a wonderful delight, that I have alwaies in my Study
before my eye such a _Curious Ballance_.

Having thus in _General_ expressed his thoughts about this Invention, and
the singular pleasure, he takes in the Observations made therewith, he
descends to particulars, and in several Letters communicates them to his
Correspondent, as follows:

[Sidenote: _The Exclusion of _all_ Air is here necessary, because Air being
subject to the operation of Heat and Cold, if any of it remain in the
_Barometer_, it will cause it to vary from shewing the true Pressure of the
Air._]

1. My _Wheel-barometer_ I could never fill so exactly with _Mercury_ as to
exclude _all_ Air; and therefore I trust more {156} to a _Mercurial_ Cane,
and take all my Notes from it. This Cane is but 35. Inches long, of a very
slender Cavity, and thick Glass. This may easily be conveyed to any place,
for Trials. The Vessel for the stagnating _Mercury_, into which the said
Cane is immersed, is about two _Inches_ wide. The _Mercury_ so well fill'd,
that for some daies it would not subside, but hung to the top of the
Glass-cane. I keep it in a Closet pretty close, 9. foot high, 8. foot
broad, 15. foot long; neer a Window. This I note, because possibly the
closeness of the room may hinder, that it gives not the full of all
Changes, as it might in a more passable Air.

2. In all my Observations from _May_ 28. 1664 to this present (_December_
9. 1665.) the Quicksilver never ascended but very little above 30¼ Inches.

3. It ascended very seldom so high (_videl._ to 30¼ Inches) chiefly
_Decemb._ 13. 1664. the weather being fickle-fair, Evening.

4. I find by my _Calender_ of _June_ 22. 1664. at 5. in the Morning, in a
time of long setled fair weather, that the _Mercury_ had ascended about
half an Inch higher then 30: but I fear some mistake, because I then took
no impression of _wonder_ at it; yet for 3. or 4. daies, at that time it
continued high, in well-setled, fair and warm weather; most part above 30.
Inches. So that I may note, the _Mercury_ to rise as high in the hottest
_Summer_, as in the coldest _Winter-weather_.

[Sidenote: _Perhaps this is from some included Air._]

5. Yet surely I have noted it ascend a little higher for the Coldness of
the Weather; and very frequently, both in {157} Winter and Summer to be
higher in the cold Mornings and Evenings, then in the warmer Mid-day.

6. Generally in setled and fair weather both of Winter and Summer, the
_Mercury_ is higher, than a little _before_ or _after_, or _in_ Rainy
weather.

7. Again, generally it descended lower after Rain, than it was before Rain.

[Sidenote: _It seems these were _Easterly_ winds._]

8. Generally also it falls in great winds; and somewhat it seem'd to sink,
when I open'd a wide door to it, to let in stormy winds; yet I have found
it to continue very high, in a long stormy wind of 3. or 4. daies.

9. Again, generally it is higher in an _East_ and _North_-wind. (_Cæteris
paribus_) than in a _South_ and _West_-wind.

10. I tryed several times, by strong fumes and thick smoaks to alter the
Air in my Closet; but I cannot affirm, that the _Mercury_ yielded any more,
then might be expected from some increase of heat. Such as have exact
_Wheel-Barometers_, may try whether Odors or Fumes do alleviate the Air.

11. In this Closet I have not in all this time found the extreamest changes
of the Quicksilver to amount to more, than to 2¾, or to 2-7/8. inches, at
most.

12. Very often I have found great changes in the Air, without any
perceptible change in the _Barometer_; as in the dewy nights, when the
moisture descends in a great quantity, and the thickness sometimes seems to
hide the Stars from us: In the days foregoing, and following, the Vapors
have been {158} drawn up so _Invisibly_, that the Air and Sky seem'd very
clear all day long. This I account a great change between ascending and
descending Dews and Vapors (which import Levity and Weight,) and between
thick Air and clear Air: which changes do sometimes continue in the
Alternative course of day and night, for a week or fortnight together; and
yet the _Baroscope_ holding the same.

13. Sometimes (I say not often) the _Baroscope_ yields not to other very
great changes of the Air. As lately (_December_ 18.) an extraordinary
bright and clear day; and the next following quite darkened, some Rain and
Snow falling; but the _Mercury_ the same: so in high winds and calms the
same.

14. I do conceive, that such as converse much _Sub dio_, and walk much
abroad, may find many particulars much more exactly, then I, who have no
leisure for it, can undertake. To instance in one of many, _December_ 16.
last, was a clear cold day, very sharp and strong _East_ wind, the
_Mercury_ very near 30. inches high, about three in the afternoon, I saw a
large black cloud, drawing near us from the _East_ and _South-East_, with
the _East-wind_. The _Mercury_ changed not that day nor the day following;
the Stars and most of the sky were very bright and clear till Nine of the
Clock; and then suddenly all the sky was darkned, yet no change of weather
happened; _December_ 17. the frost held, and 'twas a clear day, till about
two of the clock in the afternoon; and then many thick clouds appear'd low
in the _West_; yet no change of the weather here; the Wind, Frost, and
Quick-silver, the same, _December_ 18. the _Mercury_ fell almost ¼ of an
inch, and the sky and Air so clear and bright and cold with an _East-wind_,
that I wondred what could cause the _Mercury_ to descend. I Expected, it
should have ascended, as usually it does in such clear skys. Casually I
sent my servant abroad, and he discovered the remote Hills, about 20. miles
off, cover'd with {159} snow, This seem'd to manifest, that the Air, being
discharged of the clouds by snow, became lighter.

15. I have seldom seen the change to be very great, at any one time. For,
though I do not now take a deliberate view of my Notes, yet I wonder'd once
to see, that in one day it subsided about ¾ of an inch.

16. Of late I have altered my Method upon the _Barometer_, observing it, as
it is before my Eyes, all day long, and much of the night, being watchful
for the moments of every particular change, to examine, what cause in the
Air and Heavens may appear for such changes. And now my wonder is, to see,
how slow it is, it holding most between the nine and twentieth and
thirtieth inch of late.

17. I must now (_January_ 13. 1665/6) tell you, that the _Mercury_ stands
at this time (as it did also yesterday) a quarter above 30. inches; yet
both days very dark and cloudy, sometimes very thick and misty Air; which
seldom falls out. For, for the most part, I see it higher in clearest
setled weather, than in such cloudy and misty Foggs. This thick Air and
darkness hath lasted above a week; lately more Cold, and _East_ and
_North-East_ wind.

[Sidenote: _This seems to be wished, because the motion of the _Mercury_
may be more free in a wider Cane._]

_Thus far_ the Notes of this Observing _Divine_; of which Mr. _Boyle_, to
whom they were also communicated, entertains these thoughts, that they seem
to him very faithfully made, and do for the main, agree well enough with
his observations, as far as he remembers, not having them, it seems, at
that time, when he wrote this, at hand; and though it be wished by him,
that the Observer's Glass-Cane had been somewhat bigger; yet his diligence
in fitting it so carefully, or rather so skilfully, as is above-mentioned,
is much by him commended. {160}

       *       *       *       *       *

_Some Observations of _Vipers_._

A curious _Italian_, called _Francesco Redi_, having lately had an
opportunity, by the great number of Vipers, brought to the _Grand Duke_ of
_Toscany_ for the composing of _Theriac_ or _Treacle_, to examine what is
vulgarly delivered and believed concerning the Poyson of those Creatures,
hath, (according to the account, given of it in the French _Journal des
Scavans_, printed _January_ 4. 1665/6) performed his undertaking with much
exactness, and published in an Italian tract, not yet come into _England_,
these Observations.

1. He hath observed, that the poyson of Vipers is neither in their _Teeth_,
nor in their _Tayle_, nor in their _Gall_: but in the two _Vesicles_ or
_Bladders_, which cover their teeth, and which coming to be compressed,
when the Vipers bite, do emit a certain yellowish Liquor, that runs along
the teeth and poysons the wound. Whereof he gives this proof, that he hath
rub'd the wounds of many Animals with the _Gall_ of Vipers, and pricked
them with their _Teeth_, and yet no considerable ill accident follow'd upon
it, but that as often as he rubbed the wounds with the said yellow Liquor,
not one of them escaped.

2. Whereas commonly it hath hitherto been believed, that the poyson of
Vipers being swallowed, was present death; this _Author_, after many
reiterated Experiments, is said to have observed, that in Vipers there is
neither Humour, nor Excrement, nor any part, not the _Gall_ it self, that,
being taken into the Body, kills. And he assures, that he hath seen men
eat, and hath often made Bruit Animals swallow all that is esteem'd most
poysonous in a Viper, yet without the least mischief to them. Whence he
shews, that it needs not so much to be wondred at, that certain _Empiricks_
swallow the juyce of the {161} most venomous Animals without receiving any
harm thereby; adding, that, which is ascribed to the vertue of their
_Antidote_, ought to be attributed to the nature of those kinds of Poysons,
which are no poysons, when they are swallow'd, (for which Doctrine he also
alledges _Celsus_) but onely when they are put into wounds. Which also has
been noted by _Lucan_, who introduces _Cato_ thus speaking;

  _Noxia serpentum est admisto sanguine pestis,_
  __Morsu_ virus habent, & fatum _dente_ minantur;_
  __Pocula_ morte carent._

And what also some Authors have affirm'd, _videl._ That it is mortal, to
eat of the Flesh of creatures killed by Vipers; or to drink of the Wine
wherein Vipers have been drowned; or to suck the wounds that have been made
by them, is by this Authour observed to be wide of truth. For he assures,
that many persons have eaten Pullets and Pigeons, bitten by Vipers, without
finding any alteration from it in their health. On the contrary, he
declares, That it is a soveraign Remedy against the biting of Vipers, to
suck the wound; alledging an Experiment, made upon a Dog, which he caused
to be bitten by a Viper at the nose, who by licking his own wound saved his
life. Which he confirms by the example of those people, celebrated in
_History_ by the name of _Marsi_ and _Psilli_, whose Employment it was, to
heal those, that had been bitten by Serpents, by sucking their wounds.

3. He adds, that although _Galen_ and many modern _Physitians_ do affirm,
that there is nothing, which causeth so much thirst, as Vipers-flesh, yet
he hath experimented the contrary and knows divers persons, who did eat the
flesh of Vipers at all their meals, and yet did assure him, they never were
less dry, then when they observed that kind of Diet.

4. As for the Salt of Vipers, whereof some _Chymists_ have {162} so great
esteem, he saith, that it hath no _Purging_ vertue at all in it; adding
that even of _All Salts_, none hath more vertue than another, as he
pretends to have shew'd in an other _Book_ of his, _De natura salium_;
which also hath not been yet transmitted into these parts.

5. He denies, what _Aristotle_ assures, and what _Galen_ saith to have
often tryed, that the _Spittle_ of a _Fasting_ person kills Vipers; and he
laughs at many other particulars, that have been delivered concerning the
_Antipathy_ of Vipers unto certain things; and their manner of Conception
and Generation, and several other properties, commonly ascribed to them;
which the alledged French Author affirms to be refuted by so many
experiments made by this _Italian_ Philosopher, that it seems to him, there
is no place left for doubting, after so authentick a testimony.

       *       *       *       *       *

_Advertisement._

The _Reader_ of these _Transactions_ is desired to correct these _Errata_
in _Number_ 8. _viz._ page. 132. line penult. read _Wine_ for _Lime_; and
page 133. line 10. read _Thresher_ for _Trepher_, as some _Copies_ have it;
and page 136. line ult. read _purifie_ for _putrifie_.

       *       *       *       *       *


_LONDON,_

Printed for _John Martyn_ and _James Allestree_, Printers to the Royal
Society. 1666.

{163}

       *       *       *       *       *




_Num._ 10.

PHILOSOPHICAL
_TRANSACTIONS._

       *       *       *       *       *

_Munday_, _March_ 12. 1665/6.

       *       *       *       *       *

The Contents.

    _Observations continued upon the _Barometer_, or _Ballance of the Air_.
    A Relation concerning the _Earth-quake_ neer _Oxford_; together with
    some Observations of the sealed _Weatherglass_ and _Barometer_
    thereupon by _Dr. Wallis_. A more full and particular Account of those
    Observations about _Jupiter_, that were mention'd in Numb. 8. An
    Account of some Books, lately publisht, _videl._ Mr. _Boyles_
    Hydrostatical Paradoxes; _Steno_ de Musculis & Gladulis; _De Graeff_ de
    Natura & Usu Succi Pancreatici._

       *       *       *       *       *

_Observations continued upon the _Barometer_, or rather _Ballance of the
Air_._

These _Transactions_ being intended, _not only_ to be (by parcels) brief
Records of the Emergent Works and Productions in the Universe; Of the
Mysteries of Nature of later discoveries; And, of the growth of Useful
Inventions and Arts; _but_ also, and chiefly, to sollicite in all parts
mutuall Ayds and Collegiate endeavours for the farther advancement thereof:
We shall begin this _Second_ year of our Publications in this kind (in
which, for 3-moneths the Printing-presses were interrrupted by the publick
Calamity) with a few more particular Observations upon the _Ballance of the
Air_, as they are most happily invented and directed by Mr. _Boyle_; and
deserve to be prosecuted with care and diligence in all places.

But it is to be premised, that the Worthy person, who was alledged as the
Author of the Observations, delivered of this kind in the last of these
_Tracts_ (Dr. _Beale_) gives notice, That {164} he did not pretend to
exactness, but only to excite the carefulness of others in the several
distant places, and chiefly such, as can have the assistance of a
_Wheel-ballance_ perfectly filled: without both which aids he hopes not to
obtain all the benefits and mysteries of this Invention.

This being thus briefly intimated, the Account of the Observations
themselves, as they were extracted out of a late Letter of the same Person,
are, as followes:

[Sidenote: __Hygroscopes_ are Instruments, to discover the degrees of
Moisture and Drought of the Air._]

1. As I have fitted and filled the _Single Cane_, I can say in the general,
That I have not yet found any such infallible Prognostick of these changes
of weather, which do follow a long serenity, or setled weather. And
perchance in brighter Climats it may be constantly infallible. In these
_Northern Islands_, the Clouds are so short, and narrow, and by fickle
changes are sometimes emptied upon us, sometimes so neer, as may make so
little variation in the weight of the whole Atmosphere of Air, as may
sometimes deceive us, or smother and hide from us the causes of fixedness,
or of changes. I wish I could see a good _Calendar_ or _Journal_ taken in
taken in _Tangier_, and in some of our _Northern_ and most _Southern_ parts
of _America_. I have store of _Hygroscopes_ of divers kinds; and I do
remark them, and the sweatings of Marble, and as many other famed
Prognosticks, as I can hear off; but can find nothing so neerly indicative
of the change of weather, as this _Ballance_. Those others are often
changed by Dews, which do not at all alter the _Ballance_, nor alter the
state of the weather: And the open Weather-glass is known to signifie
nothing at certainty, having a double obedience to two Masters, sometimes
to the _Weight of the Air_, sometimes to _Heat_, as the service is
commanded.

2. And in further confirmation of this Note, I may adde to the former, That
in _January_ last 1665/6, from the _fourth_, and more especially from the
_seventh_ day, for many daies it continued very dark, so that all men
expected daily great rain; yet the _Mercury_ held very high, neer to the
greatest height; And though in those daies sometimes thick mists arose, and
some small rain fell, yet the _Quick-silver_ held at a great height: which
did indicate to me, there could _then_ be no great change of weather. As
the small rain fell, it yeilded somewhat, not much; and that does more
{165} confirm the indication. And more lately, in very dark daies, I had
the same confidence upon the same ground, and I was not disappointed.

3. Again, if the _Mercury_ ascends to a good height after the fall of rain
(as sometimes, but less often it does) then I look for a setled serenity;
but if it proceeds after rain in a descending motion, then I expect a
continuance of broken and showry weather. But in all, as I only say, _For
the most part_, so I dare not positively declare it an affirmative result,
but do refer it to the remarks of others. And this may explicate the Notes
6. and 14 of _Num._ 9. into more clearness.

4. That we find the Weather and our Bodies more chill, cold, and drooping,
when the _Mercury_ is lowest, and the Air lightest, besides other causes, I
guess, That as Air is to us the breath of life, as water is to Fishes; so,
when we are deprived of the usual measure of this our food, 'tis the same
to us, as when the water is drawn ebb from Fishes. But I would much rather
be instructed by others, then offer much in this kind.

5. The lowest descent of the _Mercury_ in all the time, since I have
observed it, was _Octob._ 26. 1665. in the Evening, when it was very near
at 27½ Inches. Which I find thus circumstanced with the weather in my
notes.

    _Oct._ 25. Morning; _Mercury_ at 28½ Inch. Great storms and much rain.

    _Oct._ 26. Morning; _Merc._ at 28. winds quiet, thick dark clouds.

    _Oct._ 26. Evening; _Merc._ at 27½. That day, and some daies following,
    the weather was variable, frequent rain, and as you see, the _Mercury_
    lower, than usual.

6. Over the place, where this _Mercurial Cane_ stands, I have set a _Wind
vane_, with purpose of exactness, of a Streamer in Brass so large, and
pointing to a Board indented in the Margin, that I can at a sure Level upon
the _Vane_, take every of the 32. points of the Wind, half points, and
quarter points, at good distance. Otherwise we may find our guesses much
deceived, as the best guessers, upon trial, do acknowledge. And this
exactness may become the _Wheel-ballance_, which shews the minutest
variations almost beyond imagination. And thus any servant, at the approach
of a thick Cloud, or other _Meteor_, higher or lower, or at the rising of a
storm or fresh wind in the night, or day, may bring a report of the Weight
of the Air, as certainly and almost as {166} easily, as of the Sun from the
_Dial_ in a Sunshine. It were good to have an _Index_ of Winds, that
discover'd as well their Ascent and Descent, as their Side-coastings.

       *       *       *       *       *

_A Relation concerning the late _Earthquake_ neer _Oxford_; together with
some Observations of the sealed Weatherglass, and the Barometer both upon
that _Phænomenon_, and in _General_._

This Relation was communicated by the excellently learned Dr. _Wallis_, as
follows:

On the 19. of _January_ 1665. _Stylo Angliæ_ (or _Jan._ 29. 1666. _stylo
novo_) at divers places neer _Oxford_, was observed a small _Earthquake_
(as at _Blechington, Stanton-St. Johns, Bril_, &c.) towards evening. In
_Oxford_ it self, I doe not hear, that it was observ'd to be an Earthquake;
yet I remember about that time (whether precisely then or not; I cannot
say) I took notice of some kind of odde shaking or heaving I observed in my
study, but did impute it to the going of Carts or Coaches, supposed to be
not far off; though yet I did take notice of it, as a little differing from
what is usual on such occasions; (and wondered the more, that I did not
hear any:) But not knowing, what else to refer it to, I thought no more of
it. And the like account I have had from some others in _Oxford_, who yet
did not think of an Earth-quake; it being a rare thing with us. Hearing
afterwards of an Earthquake observed by others; I looked on my Notes
concerning my _Thermoscope_ and _Baroscope_, to see if any alteration
considerable had then happened.

My _Thermoscope_ consists of a round large Glass, containing about half a
pint or more; from whence issues a long Cylindrical neck of Glass, about
two foot and a half in length, and less than a quarter of an inch diameter;
which neck was _hermetically_ sealed at the top, to exclude communication
with the External Air; but before the sealing of it, the whole Glass was
filled with _Spirit of Wine_ (tinged with _Cochineel_, to make it the more
discernable to the Eye) so warmed, that it filled the whole content of the
Glass; but afterwards, as it cooled, did so subside, as to leave a void
space in the upper part of the Neck. Which Instrument, so prepared, doth by
the rising or falling of the tinged liquor in the neck (consequent upon the
expanding or contracting of the whole liquor contained in it and the Ball
below) give a very nice account of the Temperature of the Air, {167} as to
_Heat_ or _Cold_: Even so nice, as that my being or not being in my Study I
find to vary its hight sometimes almost a quarter of an inch.

My _Baroscope_, I call another Instrument for estimating the _Weight_ or
_Pressure_ of the Incumbent Air, consisting of a long _Glass-tube_ of about
4. foot in length, and about a quarter of an inch Bore: which tube
(_hermetically_ sealed at the one end) being filled with Quicksilver
(according to the _Torricellian_ Experiment) is inverted, so as to have the
open end of it immersed in Stagnant Quicksilver, contained in a larger
Glass under it, exposed to the pressure of the outward Air: Out of which
open end (after such immersion) the Quicksilver in the Tube being suffered
to run out, as much as it will, into the Stagnant Quicksilver, in which
that mouth or open end is immersed, there is wont to remain (as is commonly
known to those acquainted with this Experiment) a Cylinder of Quicksilver
suspended in the Tube, about 28, 29, or 30. inches high; measuring from the
surface of the Stagnant Quicksilver perpendicularly; (but more or less,
within such limits, according as the Weight or Pressure of the Air
incumbent on the External Stagnant Quicksilver exposed to it, is greater or
less:) leaving the upper part of the Tube void. (Both which Instruments
being the contrivance of the Honourable _Robert Boyle_, they are by him
more particularly described in his _Physico-Mechanical Experiments touching
the Air, Exper._ 17. and 18. and in his _Thermometrical Discourses_,
premised to his _History of Cold_.)

Now, according to both these Instruments, having kept a daily _Register_ of
Observations for more than a whole year (saving when I have been for some
short time absent from home) I find my Notes for that day to be these.

    _January._  |_Thermoscope._|_Baroscope._        1665/6.
    Day.  Hour. |   inches.    | inches.
   19. 8. Morn. |   14-1/16.   | 29-1/2.       Hard frost. Close.
       4. Even. |   14-3/8.    | 29-1/4.       Hard frost. Cloudy.
       9. Even. |   14-3/4.    | 29-3/4.       Rain.       Wind
   20. 8. Morn. |   15-1/4.    | 28-3/4.       Sunshine.   Wind.

So that, there being in the morning (_January_ 19.) a hard frost (which
began the day before about 4. of the Clock in the {168} afternoon (_Jan._
18.) and continued (with us) till about 5. of the Clock in the afternoon of
that day, _Jan_ 19. with some fierceness) and the weather, _Jan._ 19. being
in the morning, close; and cloudy all the day, with little of Sun-shine;
the Liquor in the _Thermoscope_ was very little raised, by 4. of the Clock
afternoon, that is, but 5/16 of an inch (which, had the Sun shone, would,
it's likely, have been near an Inch:) and after that time (or somewhat
before) had there been no considerable change of weather, it would upon the
Sun's setting have fallen (and probably so it did, till about 5. of the
Clock, though I took no Observation in the interim.) But, contrary to what
would have been expected, it was at 9. of the Clock at night, higher by 1/8
of an inch, than it had been at 4. occasioned by the change of weather, the
Frost suddenly breaking, with us, between 5. and 6. of the Clock; about
which time also it began to rain, and continued raining that Evening and
good part of the Night. And the next morning I found the Liquor yet higher
by half an inch, _vid._ 15¼ inches: (by reason of the Air that night being
so much warmer, than it had been the day before;) whereas commonly it is
considerably lower in the morning, than over night.

As to the _Baroscope_, for the Weight or Pressure of the Air; I find, that
for the 11, l2, 13, 14, 15, 16, and 17. dayes, the _Mercury_ in the Tube,
was (by the ballancing Pressure of the incumbent Air on the stagnant
Quicksilver, exposed to it) kept up to the height of near 30. Inches above
the surface of the External Quicksilver, (though with some little
variation, as 30, 29-15/16, 29-7/8, 29-13/16 but never so low, all that
time, as 29¾;) which is the greatest height I have know it at, (for I do
not find that I have ever, till then, observed it to be, in my Glasses,
full 30. Inches, though it have been very near it:) the Weather having been
almost continually Foggy, or very thick Mists, all that time. _January_ 18.
it came down to 29¾, in the forenoon; and afternoon, to 29-11/16. about the
time the frost began: And _Jan._ 19. it was, at 8. in the morning, come
down to 29½; at 4. in the afternoon, to 29¼. But at 9. in the evening (when
the Earth quake had intervened) it was risen half an inch, _vid._ to 29¾.
And, by the next morning, fallen again a whole inch, _vid._ to 28¾; which
fall I attribute (at least in part) to the rain that fell in the night.

This being what I observed out of my _Register_ of these Instruments,
(which, if I had then thought of an Earthquake, I {169} should have more
nicely watched) what I have further gathered from Reports, is to this
purpose.

I hear, it was observed at _Blechington_, above 5. miles to the _North_ of
_Oxford_, and so along by _Bostol_, _Horton_, _Stanton-St. Johns_, and so
towards _Whately_, which is about 4. miles _Eastward_ from _Oxford_. Not at
all these places at the same time, but moving forward from _Blechington_
towards _Whately_. For it was at _Stanton_ about 6. of the Clock or later
(as I understand from Mr. _Boyle_, who was there at that time;) but had
been at _Blechington_ a good while sooner. And I am told, that it was taken
notice of by Doctor _Holder_ (a Member of our _Society_) who was then at
_Blechington_, to be observed by those in the further part of the Garden,
some very discernable time before it was observed by those in the House;
creeping forward from the one place to the other. What other places in the
Country it was observed at, I have not been informed: but at _Oxford_
(which, it seems, was about the skirts of it) it was so small, as would
have been hardly noted at all, had not the notice, taken of it abroad,
informed us of it.

Upon this Occasion, it will not be unseasonable to give some General
accounts of what I have in my _Thermoscope_ and _Baroscope_ observed.

My _Thermoscope_, being fitted somewhat at adventures, I have found at the
lowest to be somewhat more than 12. inches high, in the fiercest time of
the long Frost in the beginning of the last year 1665. and about 27. Inches
high, at the highest, in the hottest time of the last Summer: (which I
mention, that it may appear at what temperature in proportion, the Air was
at the time above-mentioned.) But I must add withall, that this standing
so, as never to be exposed to the Sun, but in a room, that has a window
only to the North, it would have been raised much higher than 27. inches,
if it were put in the hot Sun-shine in Summer; this, as it is placed,
giving therefore an account onely of the Temperature of the Air in
_general_, not of the immediate heat of the Sun-shine.

This Instrument, thus situated, when it is about 15. inches, or lower, is
for the most part hard frost; but seldom a frost, if higher than 16. Yet
this I have often observed, that the Air by the _Thermoscope_ has appeared
considerably colder (and the liquor lower) at sometimes when there is no
Frost, than at some other times, when the Frost hath been considerably
hard. {170}

In my _Baroscope_, I have never found the Quicksilver higher than 30.
inches, nor lower than 28. (at least, scarce discernably, not 1/16 of an
inch higher than _that_, or lower than _this_;) which I mention, not only
to shew the limits, within which I have observed mine to keep, _vid._ full
2 inches, but likewise as an Estimate of the Clearness of the Quicksilver
from Air. For, though my Quicksilver were with good care cleansed from the
Air; yet I find that which Mr. _Boyle_ useth, much better: for, comparing
his with mine at the same times, and both in _Oxford_, at no great
distance; I find his Quicksilver to stand alwaies somewhat higher than mine
(sometimes neer a quarter of an Inch;) which I know now how to give a more
probable account off, than that my Quicksilver is either heavier than his;
or else, that his is better cleansed from Air, (unless, possibly, the
difference of the Bore, or other circumstances of the Tube, may cause the
alteration; mine being a taller Tube, and a bigger Bore, than his.) And
upon like reason, as his stands higher than mine; so another less cleansed
from Air, may at the same time be considerably lower, and consequently
under 28. Inches at the lowest.

In _thick foggy_ weather, I find my Quicksilver to rise; which I adscribe
to the heaviness of the Vapours in the Air. And I have never found it
higher, than in the foggy weather above-mentioned.

In _Sunshiny_ weather it riseth also (and commonly the clearer, the more;)
which, I think, may be imputed _partly_ to the Vapors raised by the Sun,
and making the Air heavier; and _partly_ to the Heat, increasing the
Elastick or Springy power of the Air. Which latter I the rather add,
because I have sometimes observed in Sunshiny weather, when there have come
Clouds for some considerable time (suppose an hour or two) the Quicksilver
has fallen; and then, upon the Suns breaking out again, it has risen as
before.

In _Rainy_ weather, it useth to fall (of which the reason is obvious,
because the Air is lightned, by so much as falls:) In _Snowy_ weather,
likewise, but not so much as in _Rain_. And sometimes I have observed it,
upon a _Hoar-frost_, falling in the night.

[Sidenote: * _The Author of these Observations intends hereafter more
particularly to observe, _from what points_ those Winds blow, that make the
Quicksilver thus subside._]

For _Windy_ weather, I find it _generally_ to fall; and that more
universally, and more discernably, than upon Rain: (which I attribute to
the Winds moving the Air _collaterally_, and thereby not suffering it to
press so much _directly_ downwards: the like of {171} which we see in
swimming, &c.) And I have never found it lower than in high Winds.*

I have divers times, upon discerning my Quicksilver to fall without any
visible cause at home, looked abroad; and found (by the appearance of
broken Clouds, or otherwise) that it had rained not far off, though not
with us: Whereupon, the Air being then lightened, our heavier Air (where it
rained not) may have, in part, discharged it self on that lighter.

       *       *       *       *       *

_A more particular Account of those Observations about _Jupiter_, that were
mentioned in _Numb. 8_._

Since the publishing of _Numb._ 8. of these _Transactions_, where, among
other particulars, some short Observations were set down touching both the
_shadow_ of one of _Jupiter's Satellits_, passing over his Body, and that
_Permanent Spot_, which manifests the Conversion of that Planet about his
own _Axis_; there is come to hand an _Extract_ of that Letter, which was
written from _Rome_, about those Discoveries, containing an ample and
particular Relation of them, as they were made by the Learned _Cassini_,
Professor of _Astronomy_ in the University of _Bononia_. That _Extract_, as
it is found in the _French Journal des Scavans_ of _Febr._ 22. 1666. we
thus _English_.

Monsieur _Cassini_, after he had discovered (by the means of those
Excellent Glasses of 50. _palmes_, or 35. _feet_, made by M. _Campani_) the
_Shadows_, cast by the 4 Moons or _Satellits_ of _Jupiter_ upon his Diske,
when they happen to be between the Sun and Him; after he had also
distinguished their Bodies _upon_ the Diske of _Jupiter_; made the last
year some Prædictions for the Months of _August_ and _September_, noting
the dayes and hours, when the Bodies of the said _satellits_ and their
_Shadows_ should appear upon _Jupiter_, to the end that the Curious might
be convinced of this matter by their own Observations.

Some of these Prædictions have been verified not only at _Rome_, and in
other places of _Italy_, but also at _Paris_ by M. _Auzout_, the most
Celebrated and the most Exact of our _Astronomers_; and in _Holland_, by M.
_Hugens_. And we can now doubt no longer, of the rotation of the
_Satellits_ about _Jupiter_, as the Moon turns about the Earth; nor
believe, that _Jupiter_ or his _Attendants_ have any other Light, than
that, which they receive from the Sun; as some did {172} assure before
these Observations. There remained to find by Experience, whether _Jupiter_
did turn about his _Axis_, as many believe, that the _Earth_ turns about
her's. And although most _Astronomers_ had conjectur'd, it did so, either
by this Analogy, or by other Congruities, yet it was much wish'd, that we
might be assured thereof by Observations. And this it is, for which we are
obliged to M. _Cassini_, who, having by the advantage of the same Glasses
discover'd several changes, as well in the three obscure _Belts_, commonly
seen in _Jupiter_, as in the rest of his _Diske_, and having also observed
Spots in the midst of that _Planet_, and sometimes _Brightnesses_, such as
have bin formerly seen in the _Sun_, hath at length discover'd a _Permanent
Spot_ in the _Northern_ part of the most _Southern_ Belt; by the means
whereof, he hath concluded, that _Jupiter_ turns about his _Axis_ in 9.
hours, 56. minutes, and makes 29. whole circumvolutions in 12 dayes 4.
minutes of ours, and 360 in 149. dayes. For he has found, that this _Spot_
was not caused by the Shadow of any _Satellit_, as well by reason of its
Situation, as because it appeared, when there could be no Shadow. Besides,
that its motion differed from that of the Shadows, which is almost equal,
as well towards the Edges as towards the Middle of _Jupiter_: Whereas, on
the contrary, this _Spot_ hath all the accidents, that must happen to a
thing, which is upon the surface of a round Body moving; for example, to
move much more slowly towards the Edges, than towards the Middle, and to
pass over that part, which is in the middle of the Diske, equal to the half
of the _Diameter_, in the sixth part of the time, it takes to make the
whole revolution: he having seen this half pass'd over, in 99 or 100
minutes just, as it must happen, supposing the whole circumrotation is made
in 9. hours 56. minutes.

He hath not yet been able to determine the Situation of the _Axis_, upon
which this motion is made, because the _Belts_, according to which it is
made, have for some years appeared streight, though in the precedent years,
other _Astronomers_ have seen them a little crooked: Which sheweth, that
the _Axis_ of the diurnal motion of _Jupiter_ is a little inclined to the
plain of the _Ecliptick_. But in time we may discover, what certainty there
is in this matter.

[Sidenote: _These _Tables_ are not yet sent over, but, 'tis hoped, will be,
ere long._]

After this excellent Discovery, he hath calculated many _Tables_, whereof
he gives the Explication and Use in the Letters by him addressed to the
Abbot _Falconieri_. By the means of them, one may know, _when_ this _Spot_
may be seen by us. For, having first {173} considered it in relation to the
_Sun_, in respect whereof, its motion is regular, he considers the same in
relation to the _Earth_, where _We_ observe it; and shews by the means of
his _Tables_, what is to be added or subtracted, to know, at what time the
said _Spot_ is to come into the middle of _Jupiter_'s Diske, according as
he is Oriental or Occidental. He hath also considered it in relation to an
unmovable point, which he has supposed to be the first point of _Aries_,
because we thither refer here upon Earth the beginning of all the Celestial
motions, and _there_ is the _Primum mobile_, that one would imagine, if we
were in _Jupiter_, as we do here imagine Ours of 24. hours.

The Discovery is one of the best, that have been yet made in the Heavens;
and those, that hold the Motion of the earth, find in it a full Analogy.
For, _Jupiter_ turning about the Sun, does nevertheless turn about his
_Axis_; and although he be much bigger than the Earth, he does nevertheless
turn much more swiftly than it, since he makes more than two Turns, and a
third part, for its one; and carries with him 4. Moons, as the Earth does
one.

This Observation ought to excite all Curious persons to endeavour the
perfecting of _Optick Glasses_, to the end that it may be discovered,
whether the other _Planets_, as _Mars_, _Venus_ and _Mercury_, about whom
no Moon hath as yet been discovered, do yet turn about their _Axes_, and in
how much time they do so; especially _Mars_, in whom some _Spot_ is
discover'd, and _Venus_, wherein M._Burattini_ hath signified from
_Poland_, he has observ'd Inequalities, as in the Moon.

It will be worth while, to watch for the seeing of _Jupiter_ again this
Spring, that this happy Observation may be confirmed in divers places, and
endeavours used to make new ones.

       *       *       *       *       *

_An Account of some Books, lately published._

I. _Hydrostatical Paradoxes, made out by New Experiments (for the most part
Physical, and Easie) by the Honourable Robert Boyle._ This Treatise,
promised in _Numb._ 8. of these Papers, is now come forth: And was
occasioned by the perusal of the Learned Monsieur _Paschalls_ Tract, _Of
the Æquilibrium of Liquors_, and of the _Weight of the Air_: Of which two
Subjects, the _latter_ having been more clearly made out in _England_ by
Experiments, which could not be made by Monsieur _Paschal_ and others, that
wanted the advantage of such Engines and Instruments, as have here been
frequently made use {174} off; Our Noble Author insists most upon giving us
his thoughts of the former, _videl._ the _Æquilibrium of Liquors_: Which
Discourse consisting partly of _Conclusions_, and partly of _Experiments_,
the _former_ seem to Him to be almost all of them consonant to the
Principles and Laws of the _Hydrostaticks_; but as for the _latter_, the
Experimental proofs, offered by M. _Paschall_ for his Opinions, are by our
Author esteemed such, that he confesses, he hath no mind to make use of
them: for which he alledges more reasons than one; which, doubtless, will
appear very satisfactory to Intelligent _Readers_.

Wherefore, instead of the those _Paschalian_ Experiments, there is in this
_Treatise_ deliver'd a far more Expeditious way, to make out, _not only_
most of the _Conclusions_, agreed on these two Authors, _but_ others also,
that M _Paschall_ mentions not: and that with so much more ease and
clearness, that persons, but ordinarily versed in the common principles of
_Hydrostaticks_, may readily apprehend, what is deliver'd, if they will but
bring with them a due Attention, and Minds disposed to prefer Reason and
Experience to Vulgar opinions and Authors.

It not being our _Authors_ present Task, to deliver a Body of
_Hydrostaticks_, but only some _Paradoxes_, which he conceives to be
proveable by his New way of making them out, he delivers them in as many
distinct Propositions; after each of which, he endeavours, in a Proof, or
an Explication, to show, both that it is true, and why it ought to be so.

The _Paradoxes_ themselves (after a premised _Postulatum_) are these:

1. That in Water, and other Fluids, the Lower parts are pressed by the
Upper.

2. That a lighter Fluid may gravitate or weigh upon a heavier.

3. That, if a Body, contiguous to the Water, be altogether, or in part,
lower than the highest level of the said Water, the lower part of the Body
will be pressed upward by the Water, that touches it beneath.

4. That in the Ascension of Water in Pumps, &c. there needs nothing to
raise the Water, but a Competent weight of an External Fluid.

5. That the pressure of an External Fluid is able to keep an Heterogeneous
Liquor suspended at the same height in several Pipes, though these Pipes be
of very different Diameters.

{175}

6. If a Body be placed under Water, with its uppermost Surface parallel to
the Horizon; how much Water soever there may be on this or that side above
the Body, the direct pressure susteined by the Body (for we now consider
not the Lateral nor the Recoyling pressure, to which the Body may be
exposed, if quite environed with Water) is no more, than that of a Column
of water, having Horizontal Superficies of the Body for its Basis, and the
Perpendicular depth of the Water for its height.

    And so likewise,

If the Water, that leans upon the Body, be contained in Pipes open at both
ends, the pressure of the Water is to be estimated by the weight of a
pillar of Water, whose Basis is equal to the lower Orifice of the Pipe
(which we suppose to be parallel to the Horizon) and its height equal to a
perpendicular, reaching thence to the top of the Water; though the Pipe be
much inclined towards the Horizon, or though it be irregularly shap'd, and
much broader in some parts, than the said Orifice.

7. That a Body, immersed in a Fluid, sustains a Lateral pressure from the
Fluid; and that increased, as the depth of the immersed Body, beneath the
Surface of the Fluid, increaseth.

8. That Water may be made as well to depress a Body lighter than it self,
as to buoy it up.

9. That, whatever is said of Positive Levity, a parcel of Oyl lighter than
Water, may be kept in Water without ascending in it.

10. That the cause of the Ascension of Water in Syphons, and of its flowing
through them, may be explicated without having a recourse to Nature's
abhorrency of a _Vacuum_.

11. That a Solid Body, as ponderous as any yet known, though near the Top
of the water it will sink by its own weight; yet if it be placed at a
greater depth, than that of twenty times its own thickness; it will not
sink, if its descent be not assisted by the weight of the incumbent Water.

These are the _Paradoxes_, evinced by our Authour with much evidence and
exactness, and very likely to invite Ingenious men to cultivate and to make
further disquisitions in so excellent a part of Philosophy, as are the
_Hydrostaticks_; and Art deserving great _Elogiums_, not only, upon the
account of the _Theorems_ and _Problems_, which are most of them pure and
handsome productions of Reason, very delightful and divers of them
surprising, and besides, much conducing to the clear explication and {176}
thorow-understanding of many both familiar and abstruse _Phænomena_ of
Nature; but also, upon the score of its _Practical_ use, since the
Propositions, it teaches, may be of great importance to Navigation, and to
those that inquire into the Magnitudes and Gravities of Bodies, as also to
them, that deal in Salt-works: Besides, that the _Hydrostaticks_ may be
made divers waies serviceable to _Chymists_, as the Author intimates, and
intends to make manifest, upon several occasions, in his yet unpublisht
part of the _Usefulness of Natural and Experimental Philosophy_.

These Propositions are shut up by two important _Appendixes_, whereof the
_one_ contains an Answer to seven Objections by a late learned Writer, to
evince, that the upper parts of water press not upon the lower; the
_other_, solves that difficult _problem_, why _Urinators_ or _Divers_, and
others, who descend to the bottom of the Sea, are not oppressed with the
weight of the incumbent water? where, among other solutions, _that_ is
examined, which occurs in a printed Letter of Monsieur _des Cartes_, but is
found unsatisfactory.

II. _Nicolai Stenonis de Musculis & Glandulis Observationum Specimen; cum
duabus Epistolis Anatomicis_. In the _Specimen_ it self, the Author, having
described in _general_, both the _Structure_ and the _Function_ of the
_Muscles_, applies that description to the _Heart_, to demonstrate that
_that_ is also a _true Muscle_: Observing _first_, that in the substance of
the _Heart_ there appears nothing but _Arteries, Veins, Nerves, Fibres,
Membrans_; and that that, & nothing else is found in a _Muscle_; affirming
withall, that which is commonly taught of the _Muscles_, and particularly
of the _Heart's Parenchyma_, as distinct from _Fibres_, is due, not to the
_Senses_, but the _Wit_ of _Anatomists_: so that he will not have the
_Heart_ made up of a substance peculiar to it self, nor considered as the
principle of _Innate heat_, or of _Sanguification_, or of _vital spirits_.
He observes _next_, that the _Heart_ performs the like _operation_ with the
_Muscles_, to wit, to contract the Flesh; which action how it can have a
different cause from that of the Contraction made in the _Muscles_, where
there is so great a parity and agreement in the _Vessels_, he sees not. And
as for the _Phænomena_, that occur, of the _Motion_ of the Heart, he
undertakes to explicate them all, from the _Ductus_ or _Position_ of the
_Fibres_; but refers for the performance of this undertaking to another
_Treatise_, he intends to publish.

[Sidenote: __Conglobate_ Glanduls are called those, that do consist, as it
were, of one continued substance, having an _even_ superficies; whereof
there are many in the _Mesentery_, and in other places: contra distinguisht
to those, that bear the name of _Conglomerate_ Glanduls, which are made up
of several small Kernels, such as the _Pancreas_, the _Salivating
Glanduls_, &c._]

As to his Observations about _Glanduls_, he affirms, that he has been the
First, that has discover'd that Vessel, which by him is call'd {177}
_Salivare Exterius_, passing from the _Parotides_ (or the two chief
Arteries that are on the right and left side neer the Throat) into the
Mouth, and conveying the _Spittle_: Where he also gives an account of
several other Vessels and Glanduls, some about the _Lips_; others under the
_Tongue_; others in the _Pallate_ &c. To which he adds the Vessels of the
_Eye-lids_, which have their root in the _Glanduls_ that are about the
Eyes, and serve for the _shedding of Tears_. He mentions also several
things about the _Lymphatick vessels_, and is of opinion, that the
knowledge thereof may be much illustrated by that kind of _Glanduls_ that
are called _Conglobatæ_, and by their _true_ insertion into the veins; the
mistake of the latter whereof, he conceives to have very much misled the
Noble _Ludovicus de Bills_, notwithstanding his excellent method of
_dissection_. And here he observes _first_, that all the _Lymphatick
vessels_ have such a commerce with the _Glanduls_, that none of them is
found in the body, which either has not its origine _from_, or is inserted
_into_ a _Glandule_: And _then_, that _Glanduls_ are a kind of _Strainers_,
so form'd, that whilst the Blood passes out of the Arteries into the Veins
through the small _Capillary_ vessels, the _Serous_ parts thereof, being
freed from the _Sanguineous_, are by vertue of the beat expell'd through
fit pores into the _Capilaries_ of the _Lymphaticks_, the direction of the
_Nerves_ concurring.

Of the two annex'd _Epistles_, the _First_ gives an account of the
dissection of two _Raja's_ or _Skates_, and relates that the Author found
in the bellies of these Fishes a _Haddock_ of 1½ span long, and a _Sole_, a
_Plaise_, and nine middle-sized _Sea crafishes_; whereof not only the three
former had their flesh, in the fishes stomack, turn'd into a _fluid_, and
the Gristles or Bones into a _soft_ substance, but the _Crafishes_ had
their shels comminuted into very small particles, tinging here and there
the _Chyle_ near the _Pylorus_; which he judges to be done not so much by
the heat of the Fishes stomack, as by the help of some digesting juyce.
Coming to the _Uterus_ of these Fishes, he takes occasion to examine, with
what ground several famous _Naturalists_ and _Anatomists_ have affirm'd,
that Eggs are the _uterus_ exposed or ejected out of the body of the
Animal. Taking a view of their _Heart_, he there finds but _one_ ventricle,
and discourses of the difficulty arising from thence. As for the _Lungs_,
he saw no clearer footsteps of them in these, than he had done in other
Fishes: but within the mouth he trac'd several _gaping fissures_, and found
the recesses of the _Gills_ so form'd, that the water taken in at the
mouth, being let out by these dores, cannot by them re-enter, by reason of
a skin outwardly passing over every hole, and covering it. Where he
intimates, that though Fishes have not _true_ Lungs, yet they want not a
_Succedaneum_ thereto, to wit, the _Gills_; and if _water_ may be to
Fishes, what _Air_ is to terrestrial Animals, for Respiration: affecting,
that whereas nothing is so necessary for the conservation of Animal life as
a reciprocal Access and Recess of the _Ambient_ to the sanguineous vessels,
tis all one, whether that be done by receiving the Ambient _within_ the
body, or by its gentle passing _by_ the _Prominent_ vessels of the _Gills_.

The other _Epistle_, contains some Ingenious Observations, touching the
way, by which the Chicken, yet in the shell, is nourish't, _videl._ not by
the conveyance of the _Yolk_ into the _Liver_ by the _Umbilical_ vessels,
nor into the _Stomack_ by the {178} _Mouth_, but by a Peculiar _ductus_, by
him described, into the _Intestins_, where, according to his alledged
experience, it is turn'd into _Chyle_: which he affirms, he hath
discover'd, by taking an Egge from under a brooding Hen, when the Chicken
was ready to break forth, and when he was looking for the passage of the
_Yolk_, out of its integument into the _Liver_, by finding it pass thence
into the _Intestins_, as he found the _White_ to do by the _mouth_ into the
_belly_. Whence he inclines to infer, that, since every _fætus_ takes in at
the mouth the liquor it swims in, and since the Chicken receives the
_white_ of the Egge into the _mouth_, and the _yolk_ by the new discover'd
_ductus_ into the _Intestins_, it cannot be certainly made out, that a
_part_ of the _Chyle_ is conveyed into the _Liver_, before it passes into
the _Heart_; Exhorting in the mean time the _Patrons_ of the _Liver_, that
they would produce Experiments to evince their Ratiocinations.

III. _Regneri de Graeff, de Succi Pancreatici Natura & usu, Exercitatio
Anatomico-medica._ In this Tract, the Industrious Author, after he has
enumerated the various opinions of _Anatomists_ concerning the use of that
kernelly substance; call'd _Pancreas_ (in _English_, the _Sweetbred_)
endeavours to prove experimentally that this _Glandule_ was not form'd by
Nature, to separate any _Excrementitious_ humor, and to convey it into the
_Intestins_, but to prepare an _useful_ juyce out of the Blood and Animal
Spirits, of a somewhat _Acid_ taste, and to carry the same into the Gut,
call'd _Duodenum_, to be there mixt with the Aliment, that has been in some
degree already fermented in the Stomack, for a further fermentation, to be
produced by the conflux of the said acid _Pancreatick_ juyce and some
_Bilious_ matter, abounding with volatile Salt, causing an Effervescence;
which done, that juyce is, together with the purer part of the nourishment,
carried into the _Milkie_ veins, thence into the _common receptacle_ of the
_Chyle_ and _Lymphatick liquor_, and so through the _ductus Thoracicus_
into the right Ventricle of the Heart.

This Assertion, first advanced (saith the _Author_) partly by _Gothofredus
Mobius_, partly by _Franciscus de le Boe Sylvius_, he undertakes to prove
by experiments; which, indeed, he has with much industry, tried upon
several Animals, to the end that he might collect some of this juyce of the
_Pancreas_ for a taste: which having at last obtained, and found it
somewhat _acid_, he thereupon proceeds to deliver his opinion both of the
_constitution_ and quantity of this _Succus_ in _healthy_ Animals, and the
vices thereof, in the _unhealthy_: deriving most diseases _partly_ from its
too great Acidity, or from its saltness, or harshness; _partly_ from its
paucity or redundancy: but especially, endeavouring to reduce from thence,
as all _intermittent Feavers_ (of all the _Phænomena_ whereof he ventures
to assign the causes from this _Hypothesis_) so also the _Gout, Syncope's,
Stranguries, Oppilations, Diarrhæas, Dysenteries, Hysterical_ and _Colick
passions_, &c. All which he concludes with mentioning the waies and
remedies to cure the manifold peccancy of this juyce by Evacuations and
Alterations.

This seeming to be a _new_ as well as a _considerable_ discovery, it is
hop'd, that others will by this intimation be invited to prosecute the same
by further experiments, either to confirm what this Author has started, if
true, or to rectifie it, if he be mistaken.

       *       *       *       *       *


_NOTE._

In _Fig._ 1. of _Num._ 9 of these Tracts the Graver hath placed the bended
_end_ of the _Springing Wire_ C F, above the _Wire-staple_ B, between it
and the _Ring_ E, of the _Weight_ D; whereas _that_ end should have been so
expressed, as to pass _under_ the _Wire-staple_, betwixt its two Wires,
into the said _Ring_.

       *       *       *       *       *


_London_, Printed for _John Martyn_, and _James Allestry_, Printers to the
Royal Society. 1666.

{179}

       *       *       *       *       *




_Num._ 11.

PHILOSOPHICAL
_TRANSACTIONS._

       *       *       *       *       *

_Munday_, _April._ 2. 1666.

       *       *       *       *       *

The Contents.

    _A Confirmation of the former Account, touching the late _Earth-quake_
    near _Oxford_, and the Concomitants thereof, by Mr. _Boyle_. Some
    Observations and Directions about the _Barometer_, communicated by the
    same Hand. General Heads for a _Natural History_ of a Country, small or
    great, proposed by the same. An Extract of a Letter, written from
    _Holland_, about _Preserving Ships from being Worm-eaten_. An Account
    of Mr. _Boyle's_ lately publish't Tract, entituled, _The Origine of
    Forms and Qualities_, illustrated by Considerations and Experiments._

       *       *       *       *       *

_A Confirmation of the former Account touching the late _Earth-quake_ near
_Oxford_, and the Concomitants thereof._

This Confirmation came from the Noble Mr. _Boyle_ in a Letter, to the
_Publisher_, as followeth:

[Sidenote: * _See_ Num. 10. Phil. Transactions p. 166-171; _at the time of
the printing whereof, this Relation of Mr._ Boyle _was not yet come to
hand._]

As to the _Earth-quake_, your curiosity about it makes me sorry, that,
though I think, I was the first, that gave notice of it to several of the
_Virtuosi_ at _Oxford_; yet the Account, that I can send you about it, is
not so much of the _Thing_ it self, {180} as of the _Changes of the Air_,
that accompanied it. To inform you of which, I must relate to you, that
riding one Evening somewhat late betwixt _Oxford_ & a Lodging, I have at a
place, 4 miles distant from it, the weather having been for a pretty while
Frosty, I found the Wind so very cold, that it reduced me to put on some
defensives against it, which I never since, nor, if I forget not, all the
foregoing part of the Winter was obliged to make use off. My unwillingness
to stay long in so troublesome a Cold, which continued very piercing, till
I had got half way home-ward, did put me upon galloping at no very lasy
rate; and yet, before I could get to my Lodgings, I found the Wind turned,
and felt the Rain falling; which, considering the shortness of the time,
and that this Accident was preceded by a setled Frost, was surprising to
me, and induced me to mention it at my return, as one of the greatest and
suddainest Alterations of Air, I have ever observ'd: And what changes I
found, have been taken notice of in the _Gravity_ of the _Atmosphere_ at
the same time by that Accurate Observer * Dr. _Wallis_, who then suspected
nothing of what follow'd; as I suppose, he has ere this told you himself.
Soon after, by my guess about an hour, there was a manifest _Trembling_ in
the House where I was (which stands high in comparison of _Oxford_.) But it
was not there so great, but that I, who chanced to have my thoughts busied
enough on other matters, than the weather, should not have taken notice of
it as an _Earth-quake_, but have imputed it to some other cause, if one,
that you know, whose hand is employed in this Paper, and begins to be a
diligent observer of Natural things, had not advertis'd me of it; as being
taken notice of by him and the rest of the people of the House. And soon
after there hapned a brisk Storm: whereupon I sent to make inquiry at a
place call'd _Brill_, which standing upon a much higher ground, I supposed
might be more obnoxious to the effects of the _Earth-quake_ (of which, had
I had any suspition of it, my having formerly been in one neer the _Lacus
Lemanus_, would have made me the more observant:) But the person I sent to,
being {181} disabled by sickness to come over to me (which he promis'd to
do, as soon as he could) writ me only a _Ticket_, whose substance was, That
the _Earth-quake_ was there much more considerable, than where I lodged,
and that at a Gentlemans house, whom he names (the most noted Person, it
seems, of the neighbourhood) the House trembled very much, so as to make
the Stones manifestly to move to and fro in the Parlour, to the great
amazement and fright of all the Family. The Hill, whereon this _Brill_
stands, I have observ'd to be very well stor'd with Mineral substances of
several kinds; and from thence I have been inform'd by others, that this
Earth-quake reach'd a good many miles; but I have neither leasure, nor
inclination to entertain you with uncertain reports of the Extent and other
Circumstances, especially since a little further time an inquiry may enable
me to give you a better warranted account.

       *       *       *       *       *

_Some Observations and Directions about the _Barometer_, communicated by
the same Hand, to the _Author_ of this _Tract_._

These shall be set down, as they came to hand in another Letter; _videl._

[Sidenote: * _See _Num. 9_. of the _Phil. Transact_. p. 159 the last
_paragraph_._]

As to the _Barometrical_ Observations (as for brevities sake I use to call
them) though you * guessed aright, that, when I saw those of the Learned
and Inquisitive Dr. _Beale_, I had not Mine by me, (for I left them, some
years since, in the hands of a _Virtuoso_, nor have I now the leasure to
look after those Papers;) yet since by the Communication, you have made
publick, 'tis probable, that divers Ingenious men will be invited to
attempt the like Observations, I shall (notwithstanding my present haste)
mention to you some particulars, which perhaps will not appear
unseasonable, that came into my mind upon the reading of what you have
presented the Curious.

[Sidenote: * _Some whereof have been since invited by the _Publisher_, to
give their concurrence herein_.]

When I did, as you may remember, some years agoe, publickly express and
desire that some Inquisitive men would {182} make _Baroscopical_
Observations in several parts of _England_ (if not in forrain Countries *
also;) and to assist them, to do so, presented some of my Friends with the
necessary Instruments: The declared reason of my desiring this
Correspondence was (among other things) that by comparing Notes, _the
Extent of the Atmospherical Changes, in point of Weight, might be the
better estimated_. But not having hitherto received some account, that I
hoped for, I shall now, without staying for them, intimate thus much to
you: That it will be very convenient, that the Observers take notice not
only of the _day_, but as near as they can, of the _Houre_ wherein the
height of the _Mercurial Cylinder_ is observ'd: For I have often found,
that within less than the compass of one day, or perhaps half a day, the
Altitude of it has so considerably vary'd, as to make it in many cases
difficult, to conclude any thing certainly from Observations, that agree
but in the day.

It will be requisite also, that the Observers give notice of the
_Scituation of the place_, where their _Barometers_ stand, not only,
because it will assist men to Judge, whether the Instruments were duely
perfected, but principally, because, that though the _Baroscope_ be good
(nay, because it is so) the Observations will much disagree, even when the
_Atmosphere_ is in the same state, as to Weight, if one of the Instruments
stand in a considerably higher part of the Countrey, than the other.

To confirm _both_ the foregoing admonitions, I must now inform you, that,
having in these parts two Lodgings, the one at _Oxford_, which you know
stands in a bottom by the _Thames_ side, and the other at a place four
miles thence, seated upon a moderate _Hill_, I found, by comparing two
_Baroscopes_, that I made, the one at _Oxford_, the other at _Stanton St.
Johns_, that, though the former be very good, and have been noted for such,
during some years, and the latter was very carefully fill'd; yet by reason,
that in the _Higher_ place, the incumbent part of the _Atmosphere_ must be
lighter, than in the _Lower_, there is almost {183} always between 2 and 3
Eights of an Inch difference betwixt them: And having sometimes order'd my
servants to take notice of the Disparity, and divers times carefully
observ'd it my self, when I pass'd to and fro between _Oxford_ and
_Stanton_, I generally found, that the _Oxford Barometer_ and the _other_,
did, as it were by common consent, rise and fall together so, as that in
the former the _Mercury_ was usually 3/8 higher, than in the latter.

Which Observations may teach us, that the Subterraneous steams, which
ascend into the Air, or the other Causes of the varying Weight of the
_Atmosphere_, do, many times, and at least in some places, uniformly enough
affect the Air to a greater height, than, till I had made this tryall, I
durst conclude.

But, as most of the _Barometricall_ observations are subject to exception,
so I found the formerly mentioned to be. For (to omit lesser variations)
riding one evening from _Oxford_ to _Stanton_, and having, before I took
horse, look't on the _Baroscope_ in the former of these 2. places, I was
somewhat surprised, to find at my comming to the latter, that in places no
farther distant, and notwithstanding the shortness of the time (which was
but an hour and a half, if so much) the _Barometer_ at _Stanton_ was short
of its usual distance from the _other_, near a quarter of an _Inch_,
though, the weather being fair and calm, there appear'd nothing of manifest
change in the Air, to which I could adscribe so great a Variation; and
though also, since that time, the _Mercury_ in the two Instruments hath,
for the most part, proceeded to rise and fall as before.

And these being the only Observations, I have yet met with, wherein
_Baroscopes_, at some _Distance of Place_, and _Difference of Height_, have
been compar'd (though I cannot now send you the Reflexions, I have else
where made upon them;) as the opportunity I had to make them my self,
rendred them not unpleasant to me, so perhaps the Novelty will keep them
from being unwelcome to you. And I confess, I have had some flying
suspicions, that the odd _Phænomena_ of the _Baroscope_, which have
hitherto more pos'd, than instructed us, may in time, if a {184} competent
number of Correspondents do diligently prosecute the Inquiries (especially
with _Baroscopes_, accommodated with Mr. _Hooks_ ingenious additions) make
men some _Luciferous_ discoveries, that possibly we do not yet dream off.

[Sidenote: * _This hath been inquired into, and is found, that several
Accurate and Curious persons (as the Most Noble _President of the Royal
Society_, the Lord Viscount _Brounker_, _Doctor Beale_, _Mr. Hook_ _&c._)
have observed the same._]

I know not, whether it will be worth while to add, that since I was oblig'd
to leave _London_, I have been put upon so many lesser removes, that I have
not been able to make _Baroscopical_ Observations with such a constancy, as
I have wished, but, as far as I remember, the _Quick-silver_ has been for
the most part, so high, as to invite me to take notice of it; and to desire
you to do me the favour to inquire among your correspondents whether they
have observ'd the same thing. * For, if they have, this lasting (though not
uninterrupted) Altitude of the _Quick-silver_, happening, when the Seasons
of the year have been extraordinary dry (so much as to become a grievance,
and to dry up, as one of the late _Gazettes_ informs us, some springs near
_Waymouth_, that used to run constantly) it may be worth inquiry, whether
these obstinate Droughts, may not be cleaving of the ground too deep, and
making it also in some places more porous and as it were, spungy, give a
more copious Vent, than is usual, to subterraneal steams, which adscending
into the Air, increase the gravity of it. The inducements I have to propose
this inquiry, I must not now stay to mention. But perhaps, if the
Observation holds, it may prove not useless in reference to some Diseases.

[Sidenote: * _See Number 9. _Phil. Transact._ p. 157. 5. 8 & 9. where the
Word, _Generally_, signifies no more, than _for the most part_._]

Perhaps it will be needless to put you in mind of directing those
_Virtuosi_, that may desire your Instructions about _Baroscopes_, to set
down in their Diarys not only the day of the month, and the hour of the
day, when the _Mercuries_ height is taken, but (in a distinct _Columne_)
the weather, especially the Winds, both as to the Quarters, whence they
blow (though that be not always so easy nor necessary,) and as to the
Violence or Remisness, wherewith they blow. For, though it be more
difficult, {185} than one would think, to settle any general rule about the
rising and falling of the _Quick-silver_; yet in these parts one of those,
that seem to hold oftnest, is, * that when high winds blow, the _Mercury_
is the lower; and yet that it self does sometimes fail: For, this very day
(_March_ 3.) though on that hill, where I am, the somewhat Westerly Winds
have been blustering enough, yet ever since morning the _Quick-silver_ has
been rising, and is now risen near 3/8 of an _Inch_.

I had thoughts to add something about another kind of _Baroscope_ (but
inferiour to that in use) whereof I have given some intimation in one of
the _Præliminaries_ to the _History of Cold_. But you have already too much
of a letter, and my occasions, &c.

[Sidenote: * _Dr. _Beale_ concurs with this Observation, when he saith, in
a late _Letter_ of _March 19_. to his Correspondent in _London_;_ By change
of Weather and Wind, the _Mercury_ is sunk more than an Inch, since I wrote
to you on _Munday_ last. _March_ 12. This last night, by Rain and South
wind, 'tis sunk _half an Inch_.]

_So far that Letter._ Since which time, another from the same Noble
Observer intimates, That, as for that cause of the height of the
_Quick-silver_ in Droughts, which by him is suspected to be the elevation
of steams from the _Crust_ or Superficial parts of the Earth, which by
little and little may add to the Weight of the _Atmosphere_, being not, as
in other seasons, carried down from time to time by the falling Rain, it
agrees not ill with what he has had since occasion to observe. For, whereas
about _March_ 12^{th}, at _Oxford_, The _Quick-silver_ was higher, than,
for ought he knew, had been yet observ'd in _England_, viz. above 5/16
above 30. _Inches_, upon the first considerable showers, that have
interrupted our long Drought, as he affirms, he foretold divers hours
before that the _Quick-silver_ would be very low, (a blustering Wind
concurring with the Rain) so he found it at _Stanton_ to fall 3/8 beneath
29. _Inches_.*

{186}

       *       *       *       *       *

_General Heads for a _Natural History of a Countrey_, Great or Small,
imparted likewise by Mr. _Boyle_._

It having been already intimated (_Num. 8 of Phil. Transact._ p. 140. 141.)
that divers _Philosophers_ aime, among other things, at the Composing of a
good Natural History, to superstruct, in time, a _Solid_ and _Useful_
Philosophy upon; and it being of no slight importance, to be furnisht with
pertinent Heads, for the direction of Inquirers; that lately named
_Benefactour to Experimental Philosophy_, has been pleased to communicate,
for the ends abovesaid, the following _Articles_, which (as himself did
signifie) belong to one of his _Essays_ of the unpublisht part of the
_Usefulness of Nat. and Experimen. Philosophy_.

But first he premises, that what follows, is design'd only to point at the
more _General_ heads of Inquiry, which the proposer ignores not to be
Divers of them very comprehensive, in so much, that about some of the
_Subordinate_ subjects, perhaps too, not the most fertile, he has drawn up
_Articles_ of inquisition about particulars, that take up near as much
room, as what is here to be deliver'd of this matter.

The _Heads_ themselves follow;

The things, to be observ'd in such a History, may be variously (and almost
at pleasure) divided: As, into _Supraterraneous, Terrestrial_, and
_Subterraneous_; and otherwise: but we will at present distinguish them
into those things, that respect the _Heavens_, or concern the _Air_, the
_Water_, or the _Earth_.

1. To the _First_ sort of Particulars, belong the Longitude and Latitude of
the Place (that being of moment in reference to the observations about the
Air &c.) and consequently the length of the longest and shortest days and
nights, the Climate, parallels &c. what fixt starrs are and what not seen
there: What Constellations 'tis said to be subject to? Whereunto may be
added other Astrological matters, if they be thought worth mentioning.
{187}

2. About the _Air_ may be observ'd, its Temperature, as to the first four
Qualities (commonly so call'd) and the Measures of them: its Weight,
Clearness, Refractive power: its Sublety or Grossness: its abounding with,
or wanting an _Esurine_ Salt: its variations according to the seasons of
the year, and the times of the day; What duration the several kinds of
Weather usually have: What _Meteors_ it is most or least wont to breed; and
in what order they are generated; and how long they usually last:
Especially, what Winds it is subject to; whether any of them be stated and
ordinary, &c. What diseases are Epidemical, that are supposed to flow from
the Air: What other diseases, wherein _that_ hath a share, the Countrey is
subject to; the Plague and Contagious sicknesses: What is the usual
salubrity or insalubrity of the Air; and with what Constitutions it agrees
better or worse, than others.

3. About the _Water_, may be observ'd, the Sea, its Depth, degree of
Saltness, Tydes, Currents, &c. _Next_, Rivers, their Bigness, Length,
Course, Inundations, Goodness, Levity (or their Contraries) of Waters, &c.
_Then_, Lakes, Ponds, Springs, and especially Mineral waters, their Kinds,
Qualities, Vertues, and how examined. To the _Waters_ belong also _Fishes_,
what kinds of them (whether Salt or Fresh-water fish) are to be found in
the Country; their Store, Bigness, Goodness, Seasons, Haunts, Peculiarities
of any kind, and the wayes of taking them, especially those that are not
purely _Mechanical_.

4. In the _Earth_, may be observed,

    1. _It self._

    2. Its _Inhabitants_, and its _Productions_, and these _External_, and
    _Internal_.

_First_, in the Earth _it self_, may be observ'd, its dimensions,
scituation, East, West, North, and South: its Figure, its Plains, and
Valleys, and their Extent; its Hills and Mountains, and the height of the
tallest, both in reference to the neighbouring Valleys or Plains, and in
reference to the Level of the Sea: As {188} also, whether the Mountains lye
scattered, or in ridges, and whether those run North and South, or East and
West, &c. What Promontories, fiery or smoaking Hills, &c. the Country has,
or hath not: Whether the Country be coherent, or much broken into Ilands.
What the Magnetical Declination is in several places, and the Variations of
that Declination in the same place (and, if either of those be very
considerable, then, what circumstances may assist one to guess at the
Reason as Subterraneal fires, the Vicinity of Iron-mines, &c.) what the
Nature of the Soyle is, whether Clays, Sandy, &c. or good Mould; and what
Grains, Fruits, and other Vegetables, do the most naturally agree with it:
As also, by what particular Arts and Industries the Inhabitants improve the
Advantages, and remedy the Inconveniences of their Soyl: What hidden
qualities the Soyl may have (as that of _Ireland_, against Venemous Beasts,
&c.)

_Secondly_, above the ignobler _Productions_ of the Earth, there must be a
careful account given of the _Inhabitants_ themselves, both _Natives_ and
_Strangers_, that have been long settled there: And in particular, their
Stature, Shape, Colour, Features, Strength, Agility, Beauty (or the want of
it) Complexions, Hair, Dyet, Inclinations, and Customs that seem not due to
Education. As to their Women (besides the other things) may be observed
their Fruitfulness or Barrenness; their hard or easy Labour, &c. And both
in Women and Men must be taken notice of what diseases they are subject to,
and in these whether there be any symptome, or any other Circumstance, that
is unusual and remarkable.

As to the _External_ Productions of the Earth, the Inquiries may be such as
these: What Grasses, Grains, Herbs, (Garden and Wild) Flowers, Fruit-trees,
Timber-trees (especially any Trees, whose wood is considerable) Coppices,
Groves, Woods, Forrests, &c. the Country has or wants: What peculiarities
are observable in any of them: What Soyles they most like or dislike; and
with what Culture they thrive best. What _Animals_ the Country has or
wants, both as to wild Beasts, Hawks, and other Birds of Prey; and as to
Poultrey, and {189} Cattle of all sorts, and particularly, whether it have
any _Animals_, that are not common, or any thing, that is peculiar in
those, that are so.

The _Internal_ Productions or Concealments of the Earth are here understood
to be, the riches that ly hid under the Ground, and are not already
referr'd to other Inquiries.

Among these _Subterraneal_ observations may be taken notice of, what sorts
of Minerals of any kind they want, as well as what they have; _Then_, what
Quarries the Country affords, and the particular conditions both of the
Quarries and the Stones: As also, how the Beds of Stone lye, in reference
to North and South, &c. What Clays and Earths it affords, as
Tobacco-pipe-clay, Marles, Fullers-earths, Earths for Potters wares,
Bolus's and other medicated Earths: What other Minerals it yields, as
Coals, Salt-Mines, or Salt-springs, Allom, Vitrial, Sulphur, &c. What
Mettals the Country yields; and a description of the Mines, their number,
scituation, depth, signs, waters, damps, quantities of ore, goodness of
ore, extraneous things and ways of reducing their ores into Mettals, &c.

To these General Articles of inquiries (saith their _Proposer_) should be
added; 1 _Inquiries_ about _Traditions_ concerning all particular things,
relating to that Country, as either peculiar to it, or at least, uncommon
elsewhere, 2 _Inquiries_, that require _Learning_ or _Skill_ in the
Answerer: to which should be subjoyned _Proposals_ of ways, to enable men
to give Answers to these more difficult inquiries.

_Thus far_ our Author, who, as he has been pleased to impart these
_General_ (but yet very _Comprehensive_ and greatly _Directive_) Articles;
so, 'tis hoped from his own late intimation, that he will shortly enlarge
them with _Particular_ and _Subordinate_ ones. These, in the mean time,
were thought fit to be publisht, that the Inquisitive and Curious, might,
by such an Assistance, be invited not to delay their searches of matters,
that are so highly conducive to the improvement of _True Philosophy_, and
the wellfare of _Mankind_. {190}

       *       *       *       *       *

_An Extract of a Letter, Written from _Holland_, about _Preserving of Ships
from being Worm-eaten_._

This _Extract_ is borrowed from the _French journal des Scavans_ of _Febr._
15. 1666. and is here inserted, to excite Inventive heads _here_, to
overtake the Proposer in _Holland_. The letter runs thus:

Although you have visited our Port (_Amsterdam_) I know not whether you
have noted the ill condition, our ships are in, that return from the
_Indies_. There is in those Seas a kind of small worms, that fasten
themselves to the Timber of the ships, and so pierce them, that they take
water every where; or if they do not altogether pierce them thorow, they so
weaken the wood, that it is almost impossible to repair them. We have at
present a Man here, that pretends to have found an admirable secret to
remedy this evil. That, which would render this secret the more important,
is, that hitherto very many ways have been used to effect it, but without
success. Some have imployed Deal, Hair and Lime, &c. and therewith lined
their ships; but, besides that this does not altogether affright the worms,
it retards much the ship's Course. The _Portugals_ scorch their ships,
insomuch that in the quick works there is made a coaly crust of about an
_Inch_ thick. But as this is dangerous, it happening not seldom, that the
whole vessel is burnt; so the reason why worms eat not thorow _Portugal_
ships, is conceived to be the exceeding hardness of the Timber, employed by
them.

We expect with impatience the nature and effect of this Proposition. Many
have already ventur'd to give their thoughts concerning it. Some say, there
needs no more, but to build Ships of a harder kind of Wood, than the usual.
Others having observed, that these Worms fasten not to a kind of wild
_Indian_ Pear-tree, which is highly bitter, do thereupon {191} suggest,
that the best Expedient would be, to find out a Wood having that quality.
But certainly there being now no Timber, fit for Ships, that is not known,
'tis not likely that any will be found either more hard, or more bitter,
than that, which has been hitherto employed. Some do imagine, that the
Proposer will, by certain _Lixiviums_, give to the ordinary Wood such a
quality and bitterness, as is found in the already mention'd _Indian_
Pear-tree. But this also will hardly succeed, since it will be requisite
not only to make _Lixiviums_, in great quantities at an easie rate, and
strong enough to penetrate the thick sides of a Ship, but also to make them
durable enough, not to be wash't out by the Sea. Yet notwithstanding, in
these matters one ought to suspend on's judgement, untill experience do
shew, what is to be believed of them.

_So far the Extract._ To which it may perhaps not be unseasonable to add,
that a very worthy person in _London_, suggests the Pitch, drawn out of Sea
coles, for a good Remedy to scare away these noysome insects.

       *       *       *       *       *

_An Account of a Book, very lately publish't, entituled, _The Origine of
Forms and Qualities_, illustrated by Considerations and Experiments, by the
Honourable _Robert Boyle_._

This Curious and Excellent Piece, is a kind of _Introduction_ to the
_Principles_ of the _Mechanical Philosophy_, explicating, by very
Considerable Observations and Experiments, what may be, according to such
Principles, conceived of the _Nature and Origine of Qualities and Forms_;
the knowledge whereof, either makes or supposes the Fundamental and Useful
part of _Natural Philosophy_. In doing of which, the Author, to have his
way the clearer, writes rather for the _Corpuscularian_ Philosophers (as he
is pleased to call them) in _General_, than any {192} _Party_ of them,
keeping himself thereby disengaged from adopting an _Hypothesis_, in which
perhaps he is not so throughly satisfied, and of which he does not conceive
himself to be necessitated to make use here; and accordingly forbearing to
employ Arguments, that are either grounded on, _or_ suppose _Atoms_, _or_
any _Innate Motion_ belonging to them; _or_ that the Essence of Bodies
consists in Extension; _or_ that a _Vacuum_ is impossible; _or_ that there
are such _Globuli Cælestes, or_ such a _Materia Subtilis_, as the
_Cartesians_ imploy to explicate most of the _Phænomena_ of Nature.

The _Treatise_ consisting of a _Speculative_, and an _Historical_ part, the
Author, with great modesty leaves the _Reader_ to judge; _Whether_ in the
_First_ part he hath treated of the _Nature_ and _Origine of Forms and
Qualities_ in a more Comprehensive way, than others; _Whether_ he has by
fit Examples, and other means, rendred it more intelligible, than they have
done: _Whether_ he has added any considerable number of Notions and
Arguments towards the compleating and confirming of the proposed
_Hypothesis_: _Whether_ he has with reason dismissed Arguments unfit to be
relied on; and _Whether_ he has proposed some Notions and Arguments so
warily, as to keep them from being liable to Exceptions and Evasions,
whereto they were obnoxious, as others have proposed them. And, as to the
_Second_ and _Historical_ part, he is enclin'd to believe that the _Reader_
will grant, he hath done that part of _Physicks_, he is treating of, some
service, by strengthning the doctrines of the _New Philosophy_ (as 'tis
call'd) by such particular Experiments, whose Nature and Novelty will
render them as well Acceptable as Instructive.

The _summe_ of the _Hypothesis_, fully and clearly explicated in the
_First_ Part, is this;

That all Bodies are made of _one Catholick matter_, common to them all, and
differ but in _Shape, Size, Motion_ or _Rest_, and _Texture_ of the small
parts, they consist off; from which {193} Affections of Matter, the
_Qualites_, that difference particular Bodies, result: whence it may be
rationally concluded, that one kind of Bodies may be transmuted into
another; _that_ being in effect no more, than that one Parcel of the
Universal Matter, wherein all Bodies agree, may have a _Texture_ produced
in it, like the _Texture_ of some other Parcel of Matter, common to them
both.

To this _Hypothesis_, is subjoin'd an Examination of the _Scholastick_
opinion of _Substantial Forms_; where the Author, _first_, States the
Controversie; _next_, gives the Principal reasons, that move him to oppose
that Opinion; _then_, answers the Main arguments employed to evince it;
_further_, assigns both the _First_ Cause of Forms (_God_;) and the Grand
_Second_ Cause thereof (_Local Motion_:) and _lastly_, proves the
_Mechanical_ Production of _Forms_; grounding his proof, _partly_ upon the
Manner, by which such a _Convention of Accidents_, as deserve to pass for a
_Form_, may be _produced_; as that the Curious Shapes of _Salts_ (believed
to be the admirablest Effects and strongest Proofs of _Substantial Forms_)
may be the Results of _Texture_; _Art_ being able to produce Vitriol, as
well as _Nature_: _partly_, upon the possibility of _Reproducing_ Bodies by
skill, that have been deprived of their reputed _Substantial Forms_: Where
he alledges the _Redintegration of Saltpetre_, successfully performed by
himself; though his Attempts, made upon the dissipation and re-union of
_Amber_, _Allum_, _Sea-Salt_, and _Vitriol_, proved (by reason of
_accidental_ hindrances rather, than of any impossibility in the Nature of
the Thing) less successful.

In the _Second_ and _Historical_ Part, the Author, appealing to the
Testimony of Nature, to verifie his Doctrine, sets down, _both_ some
_Observations_, of what Nature does without being over-ruled by the power
and skill of man; and some _Experiments_, wherein Nature is guided, and as
it were, mastered by Art.

The _Observations_ are four.

1. The _First_ is taken from what happens in the _Hatching of_ {194} _an
Egge_; out of the _White_ whereof, which is a substance Similar, insipid,
soft, diaphanous, colourless, and readily dissoluble in cold water, there
is by the _New_ and _Various_ contrivement of its small parts, caused by
the Incubation of the Hen, an Animal produced, some of whose parts are
opacous, some red, some yellow, some white, some fluid, some consistent,
some solid and frangible, others tough and flexible, some well, some
ill-tasted, some with springs, some without springs, &c.

2. The _Second_ is fetcht from _Water_, which being fluid, tastless,
inodorous, diaphanous, colourless, volatile, &c. may by a _Differing
Texture_ of its parts, be brought to constitute Bodies, having qualities
very distant from these, as _Vegetables_, that have firmeness, opacity,
odors, tasts, colours, Medicinal vertues; yielding also a true _Oyle_, that
refuses to mingle with _Water_, &c.

3. The _Third_, from _Inoculation_; wherein, a small _Bud_ is able to
transmute all the sap, that arrives at it, as to make it constitute a Fruit
quite otherwise qualified, then that, which is the _genuine_ production of
the Tree, so that the same sap, that in one part of the Branch constitutes
(for Instance) a _Cluster of Haws_, in another part of the same Branch, may
make a _Pear_. Where the Author mentions divers other very considerable
Effects of Inoculations, and inserts several Histories, all countenancing
his doctrine.

4. The _Fourth_, from _Putrified Cheese_; wherein, the _rotten_ part, by
the alteration of its Texture, will differ from the _Sound_, in colour,
odor, taste, consistence, vermination, &c.

The Experiments are ten.

1. _A Solution of Vitriol and Camphire_; in which by a change of Texture,
appear'd the Production of a deep colour from a {195} white Body, and a
clear Liquor without any external heat: The destruction of this Colour, by
adding only some fair water: The change of an Odorous Body, _as Camphire_,
into an Inodorous, by mixing it with a Body, that has scarce any sensible
odour of its own: The sudden restauration of the _Camphire_ to its native
scent and other qualities, by common water, &c.

2. _Sublimate, distill'd from Copper and Silver_, which both did wholly
loose their Metalline forms, and were melted into brittle lumps, with
colours quite differing from their own; both apt to imbibe the moisture of
the Air, &c.

3. _A solution of silver into Luna Cornea_: Whereby the opacous, malleable
and hardly fusible Body of _Silver_, was, by the addition of a little
spirit of salt, reduced into Chrystals, differing from those of other
Mettals; diaphanous also, and brittle, and far more easily fusible, than
Silver; wholly unlike either a Salt or a Mettal, but very like to a piece
of _Horn_, and withall insipid, though the Solution of Silver, be very
bitter, and the spirit of salt, highly sowre, &c.

4. _An Anomalous Salt_; (which the Author had not, it seems the liberty to
teach the Preparation off) whose Ingredients were purely Saline, and yet
the Compound, made up only of salt, sowre, and strongly tasted Bodies, was
rather _really_ sweet, than of any other taste , and when a little urged
with heat, its odour became stronger, and more insupportable than that of
_Aqua fortis_, _distilled Urine_ and even _spirit of salt Ammoniack_; but
yet when these Fumes settled again into salt, their odour would again prove
inoffensive, if not pleasant &c.

5. _A Sea-salt, whence Aqua fortis had been distilled_: Where the Liquor,
that came over, proved an _Aqua Regis_: the substance in the bottom, had
not onely a mild taste, and {196} affected the Pallat much more like
salt-peter, than Common salt; but was also very fusible, and inflammable,
though produced of two un-inflammable bodies: and the same substance,
consisting of _Acid_ salts, by a certain way of the Author, produced a
_Fixt_ salt.

6. _Oyle of Vitriol poured upon a Solution of Bay-salt:_ whence was
abstracted a liquor, that by the smell and Taste appeared to be a spirit of
salt. In which operation, the mixture, by working a great change of
Texture, did so alter the nature of the compounding Bodies, that the
sea-salt, though a considerably fixt Body, was distill'd over in a moderate
Fire of sand, whilst the Oyl of Vitriol, though no such gross salt, was by
the same operation so fixt, as to stay behind: Besides that the same, by a
competent heat yeilded a substance, though not insipid, yet not at all of
the taste of Sea-salt, or of any other pungent one, much less having the
highly corrosive acidity of oyl of Vitriol, &c.

7. _A dissolvent, made by pouring a strong spirit of Nitre on the rectified
Oyl of the Butter of Antimony, and then distilling off all the liquor, that
would come over, &c._ This _Menstruum_ (called by the Author _Peracutum_)
being put to highly refined Gold, destroyed its Texture, and produced,
after the method prescribed in the book, a _true Silver_, as its whiteness
in colour, dissolublenes in _Aqua fortis_, and odious Bitterness, did
manifest: which change of a Mettal, commonly esteemed to be absolutely
indestructible by Art, though it be far from being _Lucriferous_, is yet
exceedingly _Instructive_; as is also the way, the Author here adds, of
_Volatilizing_ Gold, by the power of the same _Dissolvent_.

8. _Aqua fortis, concoagulated with differing Bodies_, produced very
differing Concretes: And the same Numeral Saline Corpuscles, that being
associated with those of one Mettal, had already produced a Body eminent in
one Taste, did {197} afterwards, being freed from that Body, compose a
Liquor of a very differing taste; and after _that_ too, being combin'd with
the parties of another Mettal, did with them constitute a Body of a very
eminent Taste, as opposite as any one can be to both the other Tasts; and
yet these Saline Corpuscles, being instead of this second Mettal,
associated with such a one as that, they are driven from, did therewith
exhibite again the first of the three mention'd Tasts.

9. _Water transmuted into Earth_, though the Author saith of this
Transmutation, that it was not so perfect, as he wish'd, and as he hopes to
make it.

10. _A mixture of Oyle of Vitriol and Spirit of Wine._ These two Liquors,
being of odd Textures in reference to each other, their conjunction and
distillation made them exhibite these _Phænomena_: _vid._ That, whereas
Spirit of Wine has no great, nor good scent, and moderately dephlegm'd Oyl
of Vitriol is wont to be inodorous; the Spirit, that first came over from
their mixture, had a scent not only very differing from Spirit of Wine, but
from all things else, that the Author ever smelt; the Odor being very
fragrant & pleasant, and so subtle, that in spight of the care taken in
luting the Glasses exactly together, it would perfume the neighbouring
parts of the _Laboratory_, and afterwards smell strongly at some distance
from the Viol, wherein it was put, though stopt with a close Cork covered
with two or three several Bladders. But, after this volatile and
odoriferous Spirit was come over, and had been follow'd by an Acid Spirit,
it was at last succeeded by a strongly stinking Liquor, &c.

But _Manum de Tabula_: the Book it self will certainly give a satisfaction
far beyond what here can be said of it. {198}

       *       *       *       *       *

_Some New observations about the Planet _Mars_, communicated since the
Printing of the former sheets._

There was very lately produced a Paper, containing some observations, made
by Mr. _Hook_, about the Planet _Mars_; in the _Face_ whereof he affirmed
to have discovered, in the late months of _February_ and _March_, that
there are several _Maculæ_ or _Spotted parts_, changing their place, and
not returning to the same Position, till the next ensuing night near about
the same time. Whence it may be collected, that _Mars_ (as well as
_Jupiter_, and the _Earth_, &c.) does move about his own _Axis_, of which a
fuller account will be given hereafter, God permitting. This short and
hasty intimation of it, is intended onely to invite others, that have
opportunity, timely to make Observations, (either to confirm, or rectify)
before _Mars_ gets out of sight.

       *       *       *       *       *


Printed with Licence for _John Martyn_, and _James Allestry_, Printers to
the Royal Society. 1666.

{199}

       *       *       *       *       *




_Num._ 12.

PHILOSOPHICAL
_TRANSACTIONS._

       *       *       *       *       *

_Munday_, _May_ 7. 1666.

       *       *       *       *       *

The Contents.

    _A way of Preserving Birds taken out of the Egge, and other small
    _Fetus's_; communicated by _Mr. Boyle_. An Extract of a Letter, lately
    sent to _Sr. Robert Moray_ out of _Virginia_, concerning an unusuall
    way of Propagating Mulberry-trees there, for the better improvement of
    the _Silk-Work_; together with some other particulars, tending to the
    good of that _Royall_ Plantation. A Method, by which a Glass of a small
    Plano-Convex Sphere may be made to refract the Rayes of Light to a
    _Focus_ of a far greater distance, than is usuall. Observations about
    _Shining Worms_ in Oysters. Observations of the Effects of _Touch_ and
    _Friction_. Some particulars, communicated from forrain Parts,
    concerning the Permanent _Spott_ in _Jupiter_; and a contest between
    two Artists about _Optick-Glasses_, &c. An Account of a Book written by
    _Dr. Thomas Sydenham_, entituled, _Methodus Curandi Febres, propriis
    Observationibus superstructa_._

       *       *       *       *       *

_A way of preserving Birds taken out of the Egge, and other small
_Fætus's_; communicated by _Mr. Boyle_._

This was imparted in a Letter, as follows;

[Sidenote: * _In the Usefulness of Experimental Philosophy._]

The time of the year invites me to intimate to you, that among the other
Uses of the Experiment, I long since presented the _Society_, of preserving
Whelps taken out of the Dams womb, and other _Fætus's_, or parts of them,
in _Spirit of Wine_; I {200} remember, I did, when I was sollicitous to
observe the Processe of Nature in the Formation of a Chick, open Hens Eggs,
some at such a day, and some at other daies after the beginning of the
Incubation, and carefully taking out the _Embryo's_, embalmed each of them
in a distinct Glass (which is to be carefully stopt) in _Spirit of Wine_:
Which I did, that so I might have them in readinesse, to make on them, at
any time, the Observations, I thought them capable of affording; and to let
my Friends at other seasons of the year, see, _both_ the differing
appearances of the Chick at the third, fourth, seventh, fourteenth, or
other daies, after the Eggs had been sate on, _and_ (especially) some
particulars not obvious in Chickens, that go about; as the hanging of the
Gutts out of the _Abdomen_, &c. How long the tender _Embryo_ of the Chick
soon after the _Punctum saliens_ is discoverable, _and_ whilst the Body
seems but a little Organized Gelly, _and_ some while after _That_, will be
this way preserv'd, without being too much shrivel'd up, I was hindred by
some mischances to satisfie my self: but when the _Fætus's_, I took out,
were so perfectly formed as they were wont to be about the seventh day, and
after, they so well retain'd their shape and bulk, as to make me not repent
of my curiosity: And some of those, which I did very early this Spring, I
can yet shew you. I know I have mention'd to you an easie application of
what I, some year since, made publick enough; but not finding it to have
been yet made by any other, and being perswaded by Experience, that it may
be extended to other _Fætus's_, which this season (the _Spring_) is time to
make provision off, I think the _Advertisement_ will not seem unseasonable
to some of our Friends; though being now in haste, and having in my
thoughts divers particulars, relating to this way of Preserving Birds taken
out of the Egge, and other small _Fætus's_, I must content my self to have
mention'd that, which is _Essential_, leaving divers other things, which a
little practise may teach the Curious, unmention'd. Notwithstanding which,
I must not omit these two Circumstances; the _one_, that when the Chick was
grown big, before I took it out of the Egge, I have (but not constantly)
{201} mingled with the _Spirit of Wine_, a little Spirit of _Sal
Armoniack_, made (as I have elsewhere delivered) * by the help of
_Quick-lime_: which Spirit I choose, because, though it abounds in a Salt
not Sowre, but Urinous, yet I never observed it (how strong soever I made
it) to coagulate Spirit of Wine. The _other_ circumstance is, that I
usually found it convenient, to let the little _Animals_, I meant to
imbalme, lie for a little while in ordinary Spirit of Wine, to wash off the
looser filth, that is wont to adhere to the Chick, when taken out of the
Egge; and then, having put either the same kind of Spirit, or better upon
the same Bird, I suffer'd it to soak some hours (perhaps some daies, _pro
re nata_) therein, that the Liquor, having drawn as it were what Tincture
it could, the _Fætus_ being remov'd into more pure and well dephlegm'd
Spirit of Wine, might not discolour it, but leave it almost as limpid, as
before it was put in.

       *       *       *       *       *

_An Extract of a Letter, sent lately to Sir _Robert Moray_ out of
_Virginia_, concerning an _unusual_ way of propagating _Mulberry trees_
there, for the better improvement of the _Silk-Work_; together with some
other particulars, tending to the good of that _Plantation_._

I am disappointed at this time of some Rarities of Minerals, Mettals, and
Stones; but you may have them any other time, as conveniently, &c. I have
planted here already ten thousand _Mulberry trees_; and hope, within two or
three years, to reap good silk of them. I have planted them in a way
unusual here, which advances them two or three years growth, in respect of
their being sown in seed: And they are now, at writing hereof all holding
good, although this has been a very long and bitter winter with us, much
longer and colder, than ever I did find it in _Scotland_ or _England_. I
intend likewise to plant {202} them all, as if they were _Currants_ or
_Goos-berries_, so thick as hedges; whereby one man may gather as many of
them, as otherwise, when they are planted in trees at distance, four
persons my do. Expedient is the benefit of this Trade. Having discoursed of
this new way to all here; they are generally inclinable to it; considering
that the Planting their Trees, as before, at distance, and letting them
grow high, has been the main obstruction of that work hitherto, and the
loss of their time and gain: but being in hedges, they will be always young
tender plants; and consequently will be easily cut in great quantities with
a pair of Garden Sizzers. But there may be suggested yet another, and
perhaps a better way; which is, to sowe some Acres with _Mulberry seed_,
and to cut it with a sith, and ever to keep it under. I have also bethought
my self of a new way, for a few hands to serve many Worms, and that more
cleanly than before: which also will be a means, without more trouble or
pains, to separate unhealthy worms from healthful; and by which a great
many more may be kept in a room, than otherwise upon shelves, as is usual
here. Besides this, I have sown a little _French Barley_ and _Rice seed_,
and am thinking on a way of un-husking them with expedition, and so
preparing them for the Merchant, as they use to be: But if you can inform
me, how they are prepared, you may save me some labour. If I had any
_Coffee_ in husks, or any other vegetable commodity, from the Streights to
try, I would here make tryal with them. Its like, that some of those
Merchants that are of your _Society_, and keep a Correspondency there, may
assist in procuring them. By the latter ships I intend to send you a New
sort of sweet sented _Tobacco_, which I have not yet had time to improve.

       *       *       *       *       *

_A Method, by which a Glass of a small Plano-convex Sphere may be made to
refract the Rayes of light to a _Focus_ of a far greater distance, than is
usual._

This is proposed by Mr. _Hook_, in consequence of what was {203} mention'd
from him in _Numb._ 4 _pag._ 67, of these _Transactions_.

Prepare (_saith he_) two Glasses, the one exactly flat on both sides, the
other flat on the one side, and convex on the other, of what Sphere you
please. Let the flat Glass be a little broader than the other. Then let
there be made a Cell or Ring of Brass, very exactly turn'd, into which
these two Glasses may be so fastened with Cement, that the plain surfaces
of them may lye exactly paralell, and that the Convex-side of the
Plano-convex-Glass may lye inward; but so, as not to touch the flat of the
other Glass. These being cemented into the Ring very closely about the
edges, by a small hole in the side of the Brass-ring or Cell, fill the
interposed space between these two with _Water_, _Oyl of Turpentine_,
_Spirit of Wine_, _Saline Liquors_, _&c;_ then stop the hole with a screw:
and according to the differing refraction of the interposed Liquors, so
shall the _Focus_ of the compound Glass be longer or shorter.

But this (adds the _Proposer_) I would only have look't upon, as one
instance of many (for there may be others) of the _Possibility_ of making a
Glass, ground in a smaller Sphere, to constitute a Telescope of a much
greater length: Though (not to raise too great exspectation) I must add,
That of _Spherical_ object glasses, those are the best, which are made of
the greatest Sphere, and whose substance hath the greatest refraction.

       *       *       *       *       *

_Observations about _Shining Worms_ in Oysters._

These Observations occur in the _French journal_ of _April_ 12. 1666. in
two letters, written by M. _Auzout_ to M. _Dela Voye_; whereof the
substance may be reduced to the following particulars.

1. That M. _Dela Voye_ having observed, as he thought, {204} some shining
Worms in Oysters; M. _Auzout_, being made acquainted with it, did first
conceive, they were not Worms (unless they were crushed ones) that shin'd,
as having not been able then to discern any parts of a Worm; but only some
shining clammy moysture; which appeared indeed like a little Star of a
blewish colour, and stuck to the Oyster-shell; being drawn out, shone in
the Air its whole length (which was about four or five lines,) and when put
upon the _Observers_ hand, continued to shine there for some time.

2. That M. _Auzout_ afterwards, causing more than 20. douzen of Oysters to
be open'd at Candle-light, really saw, in the dark, such shining worms in
them; and those of three sorts. _One_ sort was whitish, having 24. or 25.
feet on each side, forked; a black speck on one side of the head (taken by
him for a _Chrystallin_) & the back like an Eele, stript off her skin. The
_second_, red, and resembling the common _Glow-worms_, found at Land, with
folds upon their backs, and feet like the former; and with a nose like that
of a dog, and one eye in the head. The _third_ sort was speckled, having a
head like that of a Sole, with many tufts of whitish hair on the sides of
it,

3. That, besides these, the _Observer_ saw some much bigger, that were
grayish, with a big head, and two horns on it, like those of a Snayl, and
with 7. or 8. whitish feet, but these, though kept by him in the night,
shin'd not.

4. That the two first sorts are made of a matter easily resoluble, the
least shaking or touch turning them in into a viscous and aqueous matter;
which falling from the shell, stuck to the _Observers_ fingers, and shone
there for the space of 20. seconds: and if any little part of this matter,
by strongly shaking the shell, did fall to the ground, it appear'd like a
little piece of a flaming Brimstone; and when shaken off nimbly, it became
like a small shining Line, which was dissipated before it came to the
ground.

{205} 5. That this shining matter was of different colour; some, whitish,
some, reddish; but yet that they afforded both, a light which appear'd a
violet to his eye.

6. That it is very hard to examine these worms entire (especially the white
ones) because that at the least touch they doe burst, and resolve into a
glutinous moysture; whence also if it were not for their feet, that are
discover'd in their matter, none would judge them to be Worms.

7. That among those, which he observed, he saw two more firm, than the
rest, which shone all over; and when they fell from the Oyster, twinkled
like a great star, shining strongly, and emitting rays of a violet-light by
turns, for the space, (as touch't above) of 20. seconds. Which
Scintillation the _Observer_ imputes to this, that those worms being alive,
and sometimes raising their head, sometimes their tayle, like a Carpe, the
light increased and lessened accordingly; seeing that, when they shone not,
he did, viewing them by a Candle, find them dead.

8. That forcibly shaking the Oyster-shells in the dark, he sometimes saw
the whole shell full of lights, now and then as big as a fingers end; and
abundance of this clammy matter, both red and white, (which he judges to
have been Worms) burst in their holes.

9. That in the shaking he saw all the Communications of these little
Verminulous holes, like to the hole of Worms in Wood.

10. That in more than 20 douzen of Oysters he shook no shell (10. or 12.
excepted) but it emitted light: And found some of this light in sixteen of
the Oysters themselves.

11. That this light occurs more frequently in big, than small Oysters; in
those that are pierced by the Worm, oftner, than {206} in those that are
not, and rather upon the Convex-side, than the other; and more in fresh
ones; than in the stale.

12. That having somewhat scaled the Convex-side of the shell, and
discover'd the Communication of the holes, wherein the often-mention'd
viscous moysture, that has any form of insects, is found; he smelt a scent,
that was like the water of a squeesed Oyster.

13. That the Worms give no light, when irritated, but if they do, the light
lasts but a very little time, whereas that which appears in those, that
were not angred before, continues a great while; the _Observer_ affirming
to have kept of it above 2 hours.

So far the _Journal des Scavans_; which intimates withal, that if the
_Observers_ had had better _Microscopes_, they could have better examin'd
this matter.

But since the curious here in _England_ are so well furnish with good ones,
'tis hoped, that they will employ some of them for further and more minute
Observations of these Worms; it being a matter, which, joyned with other
Observations, already made by some excellent persons here, (especially Mr.
_Boyle_) upon this subject of Light, may prove very luciferous to the
doctrine of it, so much yet in the dark.

       *       *       *       *       *

_Some Observations of the Effects of _Touch_ and _Friction_._

The Operations and Effects of _Touch_ and _Friction_ having been lately
much taken notice off, and being lookt upon by some, as a great _Medical_
Branch, for the curing of many diseases and infirmities; it will perhaps
not be unseasonable to mention (here also) some Observations relating
thereunto; which may give an occasion to others, to consider this subject
more, than has been done heretofore, and to make {207} further Observations
and Tryals concerning the power of the same.

And _First_, the Illustrious Lord of _Verulam_, in his _History of Life and
Death_, Histor. 6. §. 3. observes, That _Motion_ and _Warmth_ (of which
two, _Friction_ consists) draws forth, into the parts, New Juyce and
Vigour. And _Canon._ XIII. he affirms, That _Frictions_ conduce much to
_Longevity_. See the same, _Connex._ ix. §. 26. &c.

_Secondly_, The Honourable _Robert Boyle_, in his _Usefulness of
Experimental Philosophy_, _sect_ 2. _ch._ 15. considering the Body of a
Living man or any Animal, as an Engine, so composed, that there is a
conspiring communication betwixt its parts, by vertue whereof a very slight
impression of adventitious matter upon some one part, may be able to work,
on some other distant part, or perhaps on the whole Engine, a change far
exceeding, what the same adventitious matter could do upon a Body not so
contrived: Representing, I say, an Animal in this manner, and thence
inferring, how it may be alter'd for the better or worse by motions or
impulses, confessedly _Mechanicall_, observes, How some are recover'd from
swouning fits by pricking; others grow faint and do vomit by the bare
motion of a Coach; others fall into a troublesome sickness by the agitation
of a Ship, and by the Sea-air (whence they recover by rest, and by going a
shore.) Again, how in our Stables a Horse well-curried is half-fed: How
some can tell by the Milk of their Asses, whether that day they have been
well curried or not: Arguing hence, that if in _Milk_ the alteration is so
considerable, it should be so likewise in the _Blood_, or other Juyces, of
which the Blood is elaborated, and consequently in divers of the principal
parts of the Body. Where also (upon the authority of _Piso_) he refers the
Reader to the _Brasilian_ Empiricks, whose {208} wild _Frictions_, as
unskilfully as they order them, do strange things, both in _preserving
health_, and _curing diseases_; curing Cold and _Chronical_ ones by
_Friction_, as they do _Acute_ ones, by _Unction_.

_Thirdly_, The learned Dr. _John Beale_, did not long since communicate by
some Letters; _First_, that he could make good proof of the curing or
killing a very great and dangerous _Wen_ (that had been very troublesome
for two or three years,) by the application of a dead mans hand, whence the
Patient felt such a cold stream pass to the Heart, that it did almost cause
in him a fit of swouning. _Secondly_, that, upon his brothers knowledge, a
certain Cook in a Noble Family of _England_ (wherein that brother of his
then lived) having been reproached for the ugliness of his _Warty_ hands,
and return'd for answer, that he had tried many remedies, but found none,
was bid by his Lord, to rub his hand with that of a dead man; and that this
Lord dying soon after, the Cook made use both of his Lords advise and hand,
and speedily found good effect. (Which is also confirm'd by what Mr.
_Boyle_ relates in his lately mentioned _Book_, of Dr. _Harvey's_
frequently succesfull triall, of curing some Tumors or Excrescencies, by
holding on them such a Hand.) Here is _Friction_ or _Touch_, to mortifie
Wens, to drive away swellings and Excrescencies: And why not to repell or
dissipate Spirits, that may have a dangerous influence upon the Brain, or
other parts; as well as to call forth the retired ones into the habit of
the Body, for Invigoration? _Thirdly_, that a Gentleman, who came lately
out of _Ireland_, lay at his House, and inform'd him of an aged Knight
there, who having great pain in his feet, insomuch that he was unable to
use them, suffered, as he was going to bed, a loving _Spaniell_ to lick his
feet; which was for the present very pleasing to him, so that he used it
mornings and evenings, till he found the pain appeased, and the use of his
feet restored. This, saith {209} the _Relater_, was a gentle touch, and
transpiration; for he found the Spirits transpire with a pleasing Kind of
Titillation. _Fourthly_, that he can assure of an honest Blacksmith, who by
his healing hand converted his Barrs of Iron into Plates of Silver; and had
this particular faculty, that he caused Vomitings by stroaking the Stomack;
gave the Stool by stroaking the Belly; appeased the Gout, and other paines,
by stroaking the parts affected.

       *       *       *       *       *

_Some particulars, communicated from forraign parts, concerning the
Permanent _Spott_ in _Jupiter_; and a Contest between two Artists about
_Optick Glasses_, &c._

[Sidenote: _See _Numb. 1_. of these _Transactions_; by the date whereof it
will appeare, that that _Spot_ was observed in _England_, a good while
before any such thing was so much as heard of._]

_Eustachio de Divinis_ (saith the _Informer_,) has written a large Letter,
wherein he pretends, that the Permanent Spot in _Jupiter_ hath been first
of all discovered with _his_ Glasses; and that the P. _Gotignies_ is the
first that hath thence deduced the Motion of _Jupiter_ about his _Axis_;
and that Signior _Cassini_ opposed it at first; to whom the said
_Gotignies_ wrote a letter of complaint thereupon.

The same _Eustachio_ pretends likewise, that his great Glasses excell those
of _Campani_; and that in all the tryals, made with them, they have
performed better; and that _Campani_ was not willing to do, what was
necessary for well comparing the one with the other. _viz._ To put equall
_Eye-glasses_ in them, or to exchange the same Glasses.

The said _Divini_ affirms also, that he hath found a way to {210} know,
whether an Object glass be good or not, onely by looking upon it, without
trying. This would be of good use, especially if it should extend so far as
to discerne the goodness of such a glass, whilst it is yet on the Cement.

       *       *       *       *       *

_An Account of Dr. _Sydenham's_ Book, entituled, _Methodus Curandi Febres,
Propriis observationibus superstructa_._

This _Book_ undertakes to deliver a more certain and more genuine Method of
curing Feavers and Agues, than has obtained hitherto: And it being
premised, _First_, that a Fever is Natures Engine, she brings into the
field, to remove her enemy; or her handmaid, either for evacuating the
impurities of the blood, or for reducing it into a New State: _Secondly_,
that the true and genuine cure of this sickness consists in such a
tempering of the Commotion of the Blood, that it may neither exceed, nor be
too languide: This, I say, being premised by the Author, he informs the
Reader;

In the _First Section_, of the different Method, to be employed in the cure
of Feavers, not only in respect of the differing constitutions and ages of
the patients, but also in regard of the differing seasons of one and the
same year, and of the difference of one year from another. As to the
_Former_, he shews, in what sorts of _Patients_, and at what time of the
Feaver, Phlebotomy, or Vomiting, or both, are to be used; and when and
where not: In what space of time the _Depuration_ if nature be not
disturbed or hindred in her work, will be perform'd: When _Purgatives_ are
to be administred: How that _Diarrhea's_ happen, if the _Patient_ had in
the {211} beginning of the Feaver an inclination to vomit, but no vomit was
given; and that those symptoms, which commonly are imputed to a malignity,
do, for the most part, proceed from the Relaxation of the tone of the
Bloud, caused by Medicines too refrigerating, or by the unseasonable use of
Glisters in the declination of the disease. As to the _Latter_, he
observes, that one of the chief causes, rendring the Cure of Feavers so
uncertain and unsuccessfull, is, that _Practitioners_ do accommodate their
observations, they take from the successful cure of some Feavers in one
season or the year, or in some one year, to that of all Feavers in any
season, or in any year whatsoever. And here he observes, _first_, how
vigorous the blood is in the _Spring_, and how dispirited in _Autumn_; and
thence regulates the letting of bloud, and Vomiting, and the giving of
Glisters. _Next_, how difficult it is, to assign the cause of the
difference between the Feavers of _Several years_; and to prognosticate of
the salubrity or insalubrity of the following part of the year: where yet
he insinuates, that, when _Insects_ do swarm extraordinarily, and when
Feavers and Agues (especially _Quartans_) appear very early, as about
_Midsummer_, then _Autumn_ commonly proves very sickly. _Lastly_, what
method and Cautions are to be used in the Cure of _Epidemical_ Feavers.

In the _Second Section_, he treats of the _Symptoms_, accompanying
_Continued_ Feavers; as _Phrensies_, _Pleurisies_, _Coughs_, _Hicoughs_,
_Fluxes_, &c. Shewing, both whence they are caused, and how they are to be
cured: Where having inserted a considerable _Paragraph_, touching a certain
_Symptomatical_ Feaver in the _Spring_, to be cured like Plurisies; he
mentions among many Observables, this, as a chief one, that _Laudanum_, or
any other _Narcotick_ given against the _Phrensy_, in the beginning,
progress, or height of a Feaver, does rather hurt, than good, but in the
declination thereof, is used with good success. To all which he subjoins a
particular {212} accompt of the _Iliac Passion_ (esteem'd by him to be
sometimes a _Symptome_ also of Feavers;) not only discoursing of its cause
(a preposterous inversion of the Intestins, proceeding either from
Obstruction, or Irritation,) but adding also a very plain way of Curing the
same; and that not by the use of _Quick-silver_ or _Bullets_ (by him judged
to be frequently noxious) but only by _Mint-water_; and the application of
a Whelp to the Patients stomach; to strengthen the same, and to reduce it
again to its natural motion.

In the _Third Section_, he treats of _Intermittent_ Feavers, or of _Agues_:
Where he discourses of the times of the _Cold_ and _Hot_ fits, and of
_that_ of the _Separation_ of the subdued aguish matter: Finds difficulty
in giving a satisfactory accompt of the _return of Fits_: distinguishes
Agues into _Vernal_ and _Autumnal_: Takes notice, that as there are few
_Continued_ Feavers, so generally there are only _Quotidians_ and
_Tertians_, in the _Spring_; and only _Tertians_ and _Quartans_ in
_Autumn_; Of which having offered Reasons, that seem considerable, he
proceeds to his Method of curing them; and, laying much weight upon the
said difference, he prescribes and urges different ways to be used in that
cure: Interserting among other things these notes; _First_, that the Period
of Fermentation in Feavers, both _Continued_ and _Intermittent_, is (if
left to Natures own conduct, and well regulated, if need be, by Art)
perform'd in about 336. hours or 14 dayes, subducting in _Intermittent_
ones, the hours of intermission, and counting 5½ hours for every Paroxism;
and imputing the excursion beyond that time to the disturbance given to
nature by the error of Practitioners. _Secondly_, that whoever hath had a
_Quartan_ formerly, though many years be pass'd, shall, if he chance to
have another, be _soon_ freed from it; and that a Physician knowing _that_,
may confidently predict _this_. {213}

In the _Fourth Section_, the Author, in conformity to the Custom of those
that write of Feavers, discourses of the _Small-pox_; and _First_,
examining the cause of this sickness and its universality, delivers his
peculiar opinion of the bloud's endeavouring a Renovation or a New Texture
(once at least in a Mans life) and is inclin'd to preferr the same to the
received doctrine of its malignity. _Then_, having laid down, for a
foundation of the Cure, the two times, of _Separation_ and _Expulsion_, he
argues as well against too high an Ebullition or too hasty a separation (by
a hot diet or high Cordials) as against too languid a one (by Blooding,
Purges, and Cooling medicines.) The like he does to the Time of
_Expulsion_, forbidding _both_ immoderate Heat (whereby Nature's expelling
operation is disturbed by a precipitated and too thick a crowd of the
protruded pustuls,) _and_ too much Cooling, whereby due Expulsion is
hindred. In short, he advises, to permit Nature to do her own work,
requiring nothing of the Physician, but to regulate her, when she is
exorbitant, and to fortifie her, when she is too weak. He concludes all,
with delivering a Model of the Method, he would use for his own only Son,
if he should fall into this Sickness.

       *       *       *       *       *

Advertisement.

_Whereas 'tis taken notice of, that several persons perswade themselves,
that these_ Philosophical Transactions _are publish't by the_ Royal
Society, _notwithstanding many circumstances, to be met with in the already
publish't ones, {214} that import the contrary; The Writer thereof hath
thought fit, expresly here to declare, that that perswasion, if there be
any such indeed, is a meer mistake; and that he, upon his_ Private _account
(as a Well-wisher to the advancement of usefull knowledge, and a Furtherer
thereof by such Communications, as he is capable to furnish by that
Philosophical Correspondency, which he entertains, and hopes to enlarge)
hath begun and continues both the composure and publication thereof: Though
he denies not, but that, having the honour and advantage of being a_ Fellow
_of the said_ Society, _he inserts at times some of the Particulars that
are presented to them; to wit, such as he knows he may mention without
offending them, or transgressing their Orders; tending only to administer
occasion to others also, to consider and carry them further, or to Observe
or Experiment the like, according as the nature of such things may
require._

       *       *       *       *       *


Printed with Licence for _John Martyn_, and _James Allestry_, Printers to
the Royal Society. 1666.

{215}

       *       *       *       *       *




_Numb._ 13.

PHILOSOPHICAL
_TRANSACTIONS._

       *       *       *       *       *

_Munday_, _June_ 4. 1666.

       *       *       *       *       *

The Contents.

    _Certain _Problems_ touching some Points of Navigation: Of a new
    Contrivance of _Wheel-Barometer_, much easier to be prepar'd, than
    others. An account of _Four Suns_ which lately appear'd in _France_;
    and of two, unusually posited, _Rainbows_, seen in the same Kingdom. A
    Relation of an Accident, by Thunder and Lightning, in _Oxford_. An
    Experiment, to examine, what _Figure_ or Celerity of Motion begetteth
    or increaseth _Light_ and _Flame_. Some Considerations touching a
    Letter in the _Journal des Scavans_ of _May__ 24. 1666.

       *       *       *       *       *

_Certain _Problems_ touching some Points of _Navigation_._

These _Problems_ are presented by the Learned and Industrious _Nicolaus
Mercator_, for the advancing of that Excellent and Beneficial Science,
_Navigation_, as follows:

The line of _Artificial Tangents_, or the _Logarithmical Tangent-line_,
beginning at 45 deg. and taking every half _degree_ for a whole one, is
found to agree pretty near with the _Meridian-line_ of the _Sea-Charte_;
they both growing, as it were, after the same Proportion. But the Table of
_Meridional_ degrees being calculated only to every _Sexagesimal_ minute of
a degree, shews some small difference from the said _Logarithmical
Tangent-line_. Hence it may be doubted, whether that difference do not
arise from that little errour, which is committed by calculating the Table
of _Meridional_ degrees _only_ to every minute. {216}

Mr. _Oughtred_ in the VI. _Chap._ of his _Navigation_, annexed to the Book,
entituled, _The Circles of Proportion, and the Horizontal Instrument_ &c.
mentions an Artifice, by himself discover'd, by which it may be effected,
that the small Parts of the _Meridian_ be not _one_ minute (which on the
face of the _Earth_ answers to above an _English_ Mile) but the
hundred-thousanth, or, if need be, the millioneth part of a minute, scarce
exceeding one fifteenth part of an Inch: Which thing, _he saith_, he is
able to perform in _Tables_ unto the _Radius_ 10000000; yet nothing at all
differing either in their form or manner of working from those that are now
commonly in use.

But which way this is to be done, this _Author_ hath not made known to the
Publick. And, though such _Tables_ unto the _Radius_ 10000000, had been
brought to light, yet would they not be sufficient to prove the identity or
sameness of the said two Lines, as to continue the comparison between them
as far, as the one of them, _videl._ the _Logarithmicall Tangent-line_, is
already calculated, that is; to Ten places, besides the _Charactoristick_.

Now therefore, if a certain Rule could be produced, by which the Agreement
or Disagreement of the said two Lines might be shew'd, not only to that
Extent of places, to which that _Tangent Line_ is already calculated, but
also to as many more, as the same may be yet further extended unto, in
_infinitum usque_; surely that rule would not only save us the labour of
making _Tables_ unto the _Radius_ 10000000; but also the _Helix_ or Spiral
Line of the Ships Course would be reduced to a more precise exactness, than
ever was pretended by Him: and this most Noble and Useful Science (as He
justly calls it) which is the Bond of most disjunct Countries, and the
Consociation of Nations farthest remote, would attain its full lustre and
perfection.

Besides, that the same Rule would also discover a far easier way of making
_Logarithmes_, than ever was practised or known; and therefore might serve,
when ever there should be occasion, to extend the _Logarithmes_ beyond that
number of places, that is already extant.

Moreover such a rule would enable men to draw the _Meridian_ line
_geometrically_, that is, without _Tables_ or _Scales_: which indeed {217}
might also be done, by setting of the _Secants_ of every whole or half
degree, if there were not this Inconveniency in it (which is not in my
Rule:) That a Line composed of so many small parts, would be subject to
many errours, especially in a small compass.

The same Rule also will serve, to find the Course and Distance between two
Places assigned, as far, as practice shall require it; and that, without
any Table of _Meridional_ parts, and yet with as much ease and exactness.

And seeing all these things do depend on the solution of this Question,
_Whether the Artificial Tangent-line be the true Meridian-line?_ It is
therefore, that I undertake, by God's assistance, to resolve the said
Question. And to let the world know the readiness and confidence, I have to
make good this undertaking, I am willing to lay a _Wager_ against any one
or more persons that have a mind to engage, for so much as _another
Invention_ of mine (which is of less subtlety, but of far greater benefit
to the publick) may be worth to the Inventor.

For, the great advantage, that all Merchants, Mariners, and consequently
the Common-wealth, may receive from this _other Invention_, is, in my
judgment, highly valuable; seeing it will oftentimes make a ship sail,
though, according to the common way of sailing, the wind be quite contrary,
and yet as near to the place intended, as if the wind had been favourable:
Or, if you will, it will enable one to gain something in the intended way,
whether the wind be good or no (except only when you go directly South or
North) but the advantage will be most, where there is most need of it, that
is, when the Wind is contrary: So that one may very often gain a fifth,
fourth, third part, or more of the intended voyage; according as it is
longer or shorter, _viz._ always more in a longer Voyage, where the gain is
more considerable, and more welcome; not only by saving Time, but also
Victuals, Water, Fuel, Mens health, and so much Room in the ship.

All this, which is here pretended, the Proposer is to make good by the
Verdict of some able Men, who also may give a guess, what this latter
Invention may be worth to the owner: And for so much, and no more, he will
stand engaged against {218} any one or more Persons, that he will and shall
resolve the _Question_ above-mention'd, _viz. Whether the Artificial
Tangent-line be the true Meridian-line, yea or no?_ And if he do not, that
then he will loose, and transport to the other Party the whole benefit of
the last mentioned invention. But if, on the contrary, he do prove or
disprove the Identity of the said two lines, to the Judgment of some able
_Mathematicians_, That then so much money be paid him by the other Party,
as the said Invention was valued.

And, whereas there are often Wagers laid about things that concern the
Engagers little or nothing; 'tis thought, that it would concern all
Merchants, Mariners, and all Lovers of the common good, rather to lay
wagers against one another about Things of this nature, where the Gainer
doth gain as well, as if he had laid his wager about something else, and
the Looser hath so far the benefit as well as the Gaine, That he seeth
thereby promoted the thing, that concerns them both alike.

Now therefore, to the end, that the Looser may have his benefit by it, as
well as the Gainer, it would not be amiss, that the condition were made
thus, that the latter should grant the moity of his gain to the Proposer;
that thereby he might be enabled to bring to light both those, and some
other useful inventions, for the Service of Mankind. And to manifest, that
it is not for his own interest only, that the _Proposer_ mentions this; he
is willing to impart from that moity, so received, the full moity again to
any other person within his Majesty's Dominions, who shall first of all
give notice of his Undertaking to prove or disprove the said Identity, and
perform it accordingly within the space of two Months, to be computed from
the present Date. Those that have a mind to engage, may repair to the
Printers of these _Tracts_, where they may know further.

[Illustration]

       *       *       *       *       *

_A new Contrivance of _Wheel-Barometer_, much more easy to be prepared,
than that, which is described in the _Micrography_; imparted by the Author
of that Book._

This is only an easy way of applying an _Index_ to any _Common Barascope_,
whether the Glass be only a Single Cane, or have a round Bolthead at the
top. And by the means thereof, the {219} Variation of the Altitude of the
_Mercurial_ Cylinder, which at most is hardly three Inches, may be made as
distinguishable, as if it were three Foot, or three Yards, or as much more,
as is desired.

The manner hereof is visible enough by _Figure_ I: where A B C represents
the Tube, which may be either Blunt, or with a Head, as A B C (by which
latter shape, more room is allow'd for any remainder of Air, to expand the
better.) This is to be filled with Quick-silver, and inverted as commonly;
but into a Vessel of Stagnant Mercury, made after the fashion of I K, that
is, having its sides about 3 or 4 inches high, and the Cavity of it equally
big both above and below; and if it can be (besides that part, which is
fill'd by the end of the _Mercurial_ Tube, that stands in it) of equal
capacity with the hollow of the Cane about B: For then the Quicksilver
rising as much in the hollow of I, as it descends at B, the difference of
the height in the Receiver I, will be just half the usual difference, And
if the receiving Vessel I K have a bigger Cavity, the difference will be
less, but if less, the difference will be greater: But, whether the
difference be hereby made bigger or less, 'tis no great matter, since by
the contrivance of the _Wheel_ and _Index_ (which is more fully described
in the _Preface_ to the _Micrography_) the least variation may be made as
sensible as is desired, by diminishing the bigness of the Cylinder E, and
lengthening the _Index_ F G, according to the Proportion requisite.

       *       *       *       *       *

_An Account of _Four Suns_, which very lately appear'd in _France_, and of
two _Raine-bows_, unusually posited, seen in the same Kingdom, somewhat
longer agoe._

These _Phænomena_ are thought worthy to be inserted here, for the
Speculation of the Curious in those Kingdoms; as they were publisht in the
French _Journal des Scavans_, of May 10, 1666. _viz._

The 9th of _April_ of this present year, about half an hour past nine,
there appear'd three Circles in the Sky. _One_ of them was very great, a
little interrupted, and white every where, without {220} the mixture of any
other colour. It passed through the midst of the Sun's _Disk_, and was
parallel to the _Horizon_. Its _Diameter_ was above a hundred degrees, and
its _Center_ not far from the _Zenith_.

The _Second_ was much less and defective in some places, having the Colours
of a Rainbow, especially in that part, which was within the great Circle.
It had the true Sun for its Center.

The _Third_ was less, than the first, but greater than the second; it was
not entire, but only an Arch or Portion of a Circle, whose Center was far
distant from that of the Sun, and whose circumference did, by its middle,
join to that of the least Circle, intersecting the greatest Circle by its
two extreams. In this Circle were discerned also the Colours of a Rainbow,
but they were not so strong, as those of the _Second_.

At the place, where the circumference of this _Third_ Circle did close with
that of the _Second_, there was a great brightness of Rainbow-Colours, mixt
together: And at the two extremities, where this _Second_ Circle
intersected the _First_, appear'd two _Parhelia's_ or Mock-suns; which
shone very bright, but not so bright, nor were so well defined, as the true
Sun. The False Sun, that was towards the _South_, was bigger, and far more
luminous, than that towards the _East_. Besides those two _Parhelia's_,
which were on the two sides of the true Sun, in the intersection of the
_First_ and _Third_ Circle, there was also upon the _First_ great Circle, a
_third_ Mock-sun, situated to the _North_, which was less and less bright,
than the two others. So that at the same time there were seen _Four_ Suns
in the Heavens.

[Illustration]

[Illustration]

_Figure_ II. will illustrate the Position of this _Phænomenon_.

A. _The Zenith or the Point Vertical to the place of Observation._

B. _The true Sun._

S C H N. _The great Circle, altogether White, almost parallel to the
Horizon, which pass'd through the true Sun's Diske, and upon which were the
false Suns._

D E B O. _A Rain-bow about the Sun, forming an entire Circle, but
interrupted in some places._

H D N. _A portion of a Circle, that was Excentrick to the Sun, and greater
than the Circle_ D E B O, _which touch'd_ D E B O, _and was confounded with
it in the point_ D. {221} H N. _The two Mock-Suns, in the intersection of
the Semicircle_ H D N, _and the Circle_ S C H N: _The midst of which two
False-Suns was white and very luminous; and their Extremities towards_ D I
_were tinged with the Colours of a Rainbow. The False Sun, mark'd_ N, _ was
fainter than that, which is mark'd_ H.

C. _The Mock-Sun, all white, and far less shining, than the two others._

I. _A space very dark betwixt_ R. _and_ D.

[Sidenote: * _Those _Five_ Suns, that appear'd the 29 _March_, A. 1629. at
_Rome_, between 2 or 3 of the Clock, in the afternoon, were thus posited;
that the two of them, which were in the intersection of two Circles,
appear'd in that of a Circle, which passed through the Sun's Diske, with
another, that was _Concentrick_ to the Sun: as may be seen in _Figure III_.
borrow'd (for the easier comparing them together) out of _Des-Cartes_ his
_Meteors_, cap. X._]

This Appearance is look't upon as one of the notablest, that can be seen,
by reason of the _Excentricity_ of the Circle H D N, and because that the
_Parhelia_ * were not in the Intersection of the Circle D E B O with the
great Circle S C H N, but in that of the Semi-circle H D N.

As for the two odd _Rainbows_; they appear'd at _Chartres_ the 10. of
_August_, 1665. about half an hour past six in the Evening; and did cross
one another almost at right Angles, as may be seen by _Fig._ IV.

[Illustration]

The Rainbow, which was opposite to the Sun, in the usual manner, was more
deeply colour'd, than that, which cross'd it; though even the Colours of
the first _Iris_ were not so strong, as they are now and then seen at other
times.

The greatest height of the stronger Rainbow, was about 45. degrees; the
feebler Rainbow lost one of its Legs, by growing fainter, about 20 degrees
above the stronger; and the Leg below appear'd continued to the _Horizon_.

These Rainbows did not _Just_ decussate one another at right Angles; there
was some 6 or 7 degrees difference. The fainter, seem'd to be a Portion of
a great Circle; and the stronger was but a Portion of a small Circle, as
usually.

The Sun, at their appearance, was about 6 degrees high above the _Horizon_,
and towards the 17 _Azimuth_ of the West, Northward.

{222}

The Observer, M. _Estienne_, notes, that, when he made this Observation,
the River of _Chartres_, which runs very near from _South_ to _North_, was
betwixt him and the Rainbow; and that he stood Level with this River,
whence he was distant not above 150 paces: which he adds, that the Curious
may the better judge of this Observation.

       *       *       *       *       *

_A Relation of an Accident by Thunder and Lightning, at _Oxford_._

This was imparted by Dr. _Wallis_ in a Letter, written at _Oxford_, May 12,
1666. to the _Publisher_, as follows:

I should scarce have given you so soon the trouble of another Letter, were
it not for an Accident which hapn'd here _May_ 10. I had that afternoon,
about 4 of the clock heard it thunder at some distance. About 5 of the
clock the Thunder coming nearer to us; it began to rain, and soon after
(the rain withal increasing) the Thunder grew very loud, and frequent, and
with long ratling Claps (though not altogether so great, as I have some
other times heard:) and the Lightning with flashes very bright
(notwithstanding the clear day-light) and very frequent, (when at the
fastest, scarce a full minute between one flash and another; many times not
so much, but a second flash before the Thunder of the former was heard:)
The Thunder for the most part began to be heard about 8 or 10 second
minutes after the flash; as I observ'd for a great part of the time by my
Minute-Watch: but once or twice I observ'd it to follow (in a manner)
immediately upon it, as it were in the same moment; and the lightning
extream red and fiery. I do not use to be much apprehensive of Thunder and
Lightning, but I was at this time (I know not well, why?) very
apprehensive, more than ordinary, of mischief to be done by it, for it
seem'd to me to be very low and near us (which made me so particular, as to
observe the distance of the flash by the noise) and very frequent, and
bright, so that, had it been by night as it was by day, it would have been
very terrible. And, though I kept within doors, yet I sensibly discover'd a
stinking sulphureous smell in the Air. About 7 of the clock it ended,
before which time I had news brought me of a Sad Accident upon the {223}
water at _Medley_ about a Mile or somewhat more distant from hence. Two
Schollars of _Wadham_-Colledge, being alone in a Boat (without a Water-man)
having newly thrust off from shore, at _Medley_, to come homewards,
standing near the Head of the Boat, were presently with a stroke of Thunder
or Lightning, both struck off out of the Boat into the Water, the one of
them stark dead, in whom, though presently taken out of the Water (having
been by relation, scarce a minute in it) there was not discerned any
appearance of life, sense, or motion: the other was stuck fast in the Mud
(with his Feet downwards, and his upper parts above water) like a post not
able to help himself out; but, besides a present stonying or numness, had
no other hurt; but was for the present so disturb'd in his senses, as that
he knew not, how he came there out of the Boat, nor could remember either
Thunder or Lightning, that did effect it: and was very feeble and faint
upon it; which (though presently put into a warm Bed) he had not thoroughly
recover'd by the next Night; and whether since he have or no, I know not.

Others in another Boat, about 10 or 20 yards from these (as by their
description I estimate) felt a disturbance and shaking in their Boat, and
one of them had his Chair struck from under him, and thrown upon him; but
had no hurt. Those immediately made up to the others, and (some leaping
into the Water to them) presently drew them either into the Boat or on
Shore; yet none of them saw these two fall into the Water (not looking that
way) but heard one of them cry out for help presently upon the stroke, and
smelt a strange stinking smell in the Air; which, when I asked him, that
told it me, what kind of stink? he said, like such a smell, as is perceived
upon the stricking of Flints together.

He that was dead (when by putting into a warm Bed, and rubbing, and putting
strong waters into his Mouth, &c. no life could be brought into him) was
the next morning brought to town; where, among the multitudes of others,
who came to see, Dr. _Willis_, Dr. _Mellington_, Dr. _Lower_, and my self,
with some others, went to view the Corps: where we found no wound at all in
the skin, the face and neck swart and black, but not more, than might be
ordinary, by the settling of the blood: On the right side of the neck was a
little blackish spot about an inch long, and {224} about a quarter of an
inch broad at the broadest, and was, as if it had been sear'd with a hot
iron; and, as I remember, one somewhat bigger on the left side of the neck,
below the Ear. Streight down the breast, but towards the left side of it,
was a large place about three quarters of a Foot in length, and about two
inches in breadth, in some places more, in some less, which was burnt and
hard, like Leather burnt with the fire, of a deep blackish red Colour, not
much unlike the scorch'd skin of a rosted Pig. And on the fore-part of the
left Shoulder such another spot about as big as a Shilling; but that in the
neck was blacker and seem'd more sear'd. From the top of the right
shoulder, sloping downwards towards that place in his Breast, was a narrow
Line of the like scorched skin; as if somewhat had come in there at the
neck, and had run down to the breast, and there spread broader.

The buttons of his _Doublet_ were most of them off; which, some thought
might have been torn off with the blast, getting in at the neck, and then
bursting its way out: for which the greatest presumption was (to me) that,
besides 4 or 5 buttons wanting towards the bottom of the Breast, there were
about half a dozen together clear off from the bottom of the collar
downwards, and I do not remember, that the rest of the buttons seem to be
near worn out, but almost new. The collar of his doublet just over the
fore-part of the left shoulder was quit broken asunder, cloth and
stiffening, streight downwards, as if cut or chop'd asunder, but with a
_Blunt_ tool; only the inward linnen or fustian lineing of it was whole, by
which, and by the view of the ragged Edges, it seem'd manifest to me, that
it was by the stroak inward (from without) not outwards from within.

His _Hat_ was strangely torn, not just on the Crown, but on the side of the
hat, and on the brim. On the side of it was a great hole, more than to put
in ones fist through it: some part of it being quite struck away, and from
thence divers gashes every way, as if torn, or cut with a _Dull_ tool, and
some of them of a good length, almost quite to the edges of the brim. And,
beside these, one or two gashes more, which did not communicate with the
hole in the side. This also I judged by a stroke inwards; not so much from
the view of the edges of those gashes (from which there was scarce any
judgement to be made either way) but {225} because the lining was not torn,
only ript off from the edge of the hat (where it was sow'd on) on that
side, where the hole was made. But his hat not being found upon his head,
but at some distance from him, it did not appear, against what part of the
head that hole was made.

Upon the rest of his Cloaths, I do not know of any further effect, nor did
we smell any sulphurous scent about them: which might be, _Partly_ because
it was now a good while after the time, and _Partly_ by reason of their
being presently drenched in the water into which he fell.

The night following, the three _Doctors_ above mentioned, and my self, with
some Chirurgions (besides a multitude of others) were present at the
opening of the head, to see if any thing could be there discover'd; but
there appear'd no sign of contusion; the brain full and in good order; the
nerves whole and sound, the vessels of the brain pretty full of Blood. But
nothing was by any of them discern'd to be at all amiss. But it was by
candle-light, and they had not time to make very nice Observations of it
(the Body being to be buried by and by) and the croud of People was a
further hindrance. But if any thing had been considerably out of order to
the view, it would surely have been by some of them discover'd. Some of
them thought, they discern'd a small fissure or crack in the skull; and
some who held it, while it was sawing off, said, they felt it Jarring in
their hands, and there seem'd to the eye something like it, but it was so
small, as that by candle-light we could not agree it certainly so to be.

Some of the _Hair_ on the right Temple was manifestly singed, or burnt; and
the lower part of that Ear blacker, than the parts about it, but soft; and
it might be only the settling of the Blood. The upper part of the left
shoulder, and that side of the neck, were also somewhat blacker than the
rest of the Body, but whether it were by the blow, which broke the collar,
and scorch'd the round red spot thereupon, or only by settling of the
Blood, I cannot say; yet I think, it might very well be, that both on the
head, and on this side of the neck, there might be a very great blow, and a
contusion upon it (and seems to have been so, by the tearing of the hat,
and breaking the collar, if not also cracking of the skull) and yet no sign
of such contusion, because dying so immediately, there was not time for the
Blood to gather {226} to the part and stagnate there (which in bruises is
the cause of blackness) and it was but as if such a blow had been given on
a Body newly dead; which does not use to cause such a symptom of a bruise,
after the Blood ceases to circulate.

Having done with, the Head, they open'd the _Breast_, and found that
burning to reach quite through the skin, which was in those scorch'd places
hard and horney, and shrunk up, so as it was not so thick as the soft skin
about it: but no appearance of any thing deeper than the skin; the Muscles
not at all disorder'd or discolour'd (perhaps, upon the reason, that was
but now said of the Head, Neck and Shoulder). Having then taken off the
_Sternum_, the Lungs and Heart appear'd all well, and well-colour'd without
any disorder.

This is the sum of what was observ'd; only that the whole Body was, by
night, very much swell'd, more than in the morning; and smelt very strong
and offensively: Which might be by the hotness of the weather, and by the
heat of the place occasion'd by the multitude of People.

       *       *       *       *       *

_An Experiment to examine, what _Figure_, and _Celerity_ of _Motion_
begetteth, or encreaseth _Light_ and _Flame_._

This was communicated by Dr. _Beale_, as follows;

_May_ 5. 1665. fresh Mackrels were boyl'd in Water, with salt and sweet
herbs; and, when the Water was perfectly cold, the next morning, the
Mackrels were left in the Water for pickle.

_May_ 6. more fresh Mackrels were boyl'd in like Water; and _May_ 7. both
Water and Mackrels were put into the former Water, together with the former
Mackrels. (Which circumstances I do particularize, because, whether, the
mixture of the pickle of several ages, and a certain space of time, or
whatever else was necessary, and wanting, the trial did not succeed with
like effect at other times).

But now on the next _Munday_ (_May_ 8). evening, the Cook stirring the
Water, to take out some of the Mackrels, found the Water at the first
motion become very luminous, and the Fish shining through the Water, as
adding much to the Light, which the water yielded. The water by the mixture
of Salt and Herbs, {227} in the boyling, was of it self thick and rather
blackish, than of any other clear colour: yet being stirr'd, it shin'd, and
all the fish appear'd, more brightly luminous in their own shapes.

Wherever the drops of this water (after it was stirr'd) fell on the Ground,
or Benches, they shin'd: And the Children took drops in their hands, as
broad as a penny, running with them about the house, and each drop, both
near and at distance, seem'd by their shining as broad as a six pence, or a
shilling, or broader.

The Cook turn'd up the side of the Fish, which was lowest, and thence came
no shining: and after the water was for some good time settled, and fully
at rest, it did not shine at all.

On _Tuesday_ night (_May_ 9). we repeated the same Trial, and found the
same effects. The water, till it was stirr'd, gave no light, but was thick
and dark, as we saw by day-light, and by candle-light. As soon as the
Cook's hand was thrust into the water, it began to have a glimmering; but
being gently stirr'd by the hand moving round (as the Dairy-maid do to
gather the Curds for Cheese) it did so shine, that they, who look'd on it
at some distance, from the farther end of another room, thought verily, it
was the shining of the Moon through a Window upon a Vessel of Milk; and by
brisker Circulation it seem'd to flame.

The Fish did then shine as well from the Inside, as the Outside, and
chiefly from the Throat, and such places, as seem'd a little broken in the
boyling.

I took a piece that shin'd most, and fitted it as well as I could devise in
the night, both to my great _Microscope_, and afterwards to my little one;
but I could discern no light by any of these Glasses; nor from any drops of
the shining water, when put into the Glasses. And _May_ 10. in the
brightest rayes of the Sun, I examin'd, in my great _Microscope_, a small
broken piece of the Fish, which shin'd most the night before. We could find
nothing on the surface of the Fish very remarkable. It seem'd whitish, and
in a manner dried, with deep inequalities. And others, as well as my self,
thought, we saw a stream, rather darkish, than luminous, arising like a
very small dust from the Fish: And rarely here and there, a very small; and
almost imperceptible sparkle in the Fish. Yet of these _sparkles_ we are
_certain_; we numbered them, and agreed in the number, order and place. Of
the _steam_ I am not confident, but do suspect our Eyes in the {228} bright
Sun, or that it might be some dust in the Aire.

The great _Microscope_ being fitted in the day-light for this piece of
Fish, we examin'd it that night, and it yielded no light at all, either by
the view of the Glass, or otherwise.

Finding it dry, I thought that the moisture of Spittle, and touching of it,
might cause it to shine: and so it did, though but a very little, in a few
small sparks, which soon extinguish'd. This we saw with the bare eye; not
in the Glass.

The Fish were not yet fetide, nor insipid to the best discerning palats:
And I caused two Fish to be kept for further Tryal, two or three days
longer, till they were fetide in very hot weather; and then I expected more
brightness, but could find none, either in the water, by stirring it, or in
the Fish, taken out of the water.

And some Trials I made afterwards with other boyl'd Mackrels (as is above
said) with like pickle, but failed of the like success.

This season serves for many Trials in this kind, and by better
_Microscopes_, or better ordered. And in these Vulgarities we may perhaps
as well trace out the cause and nature of Light, as in Jewels of greatest
value, &c.

       *       *       *       *       *

_Some Considerations touching a Letter in the _Journal des Scavans_ of _May
24. 1666_._

In _Num._ 9. of these _Transactions_ were publish'd the _Schemes_ and
_Descriptions_ of certain Ways of _Sounding the Depth of the Sea without a
Line_; and of _Fetching up Water from the bottom of it_; together with some
Experiments already made with the former of these two Contrivances. The
Author of the French _Journal des Scavans_ found good, to insert them both
in his _Journal_ of _May_ 3. but in another of _May_ 24. intimates, that
the said _Schemes_ and their _Descriptions_ are not very clear and
intelligible (he means, that they were not well understood by _French_
Readers) proposing also some Difficulties, relating to that Subject, and
esteemed by him necessary to be satisfied, before any use could be made of
the said Instruments.

Upon this occasion, the Author of these _Tracts_ thinks fit, here to
represent, {229}

_First_, That _Englishmen_ and such others, as are well versed in the
_English_ tongue, find no difficulty in understanding the descriptions of
these _Engines_, nor in apprehending their structure, exhibited by the
_Figures_, especially if notice be taken of the Emendation, expressed at
the end of _Num._ 10. about the misgraving the _Bended end_ of the
_Springing Wire_ (which it seems has not been noted in _France_, tho' the
said _Num._ 10 is known to have been seen there a pretty while before their
_Journal_ of _May_ 24. was publish'd). And as for the particular of the
_Bucket_, fetching water from the bottom of the Sea, both the _Figure_ and
the annexed _Description_ thereof are so plain and clear, that 'tis some
wonder here, that any difficulty of understanding them is pretended by any,
that hath but ordinary skill in _Cutts_ and the _English_ language. Mean
while, that way, which the _French_ Author recommends for this purpose as
more simple, _Videl. a Brass-Pump with double Valves_, is not at all
unknown in _England_, nor has bin left untried there; but was found
inconvenient, in respect that the Valves in descending did not fully open,
and give the water a free passage through the Cavity of the Vessel, nor in
ascending shut so close, as to hinder the water from coming in at the top:
Whereas by the way proposed in _Num._ 9. both is perform'd with great ease
and security.

_Secondly_, Whereas the _French_ Author is of opinion, that 'tis unknown,
how much time a Heavy Body requires to sink in water, according to a
certain depth; he may please to take notice, that that hath been made out
in _England_ by frequent Experiments; by which, several Depths, found by
this Method of sounding _without_ a Line, were examin'd by trying them over
again in _the same_ place _with_ a Line, after the common way. And as to
that _Quære_ of his, Whether a heavy Body descends in the same _Proportion_
of swiftness in _Water_, that it would do in _Air_? The Answer is, that it
does not; but that, after it is sunk one or two fathoms into the Water, it
has there arrived to its greatest swiftness, and keeps, after that, an
equal degree of velocity; the _Resistance_ of the water being then found
equal to the _Endeavour_ of the heavy Body downwards.

_Thirdly_, When the same _Author_ alledges that it must be known, when a
Light Body reascends from the bottom of the water to {230} the top, in what
proportion of time and swiftness it rises. He seems not to have considered,
that in this Experiment, the times of the descent and assent are both taken
and computed together; so that for this purpose, there needs not that
nicety, he discourses of.

_Fourthly_, Whereas it is further excepted, That this way of Sounding
Depths is no new Invention; The answer is ready, that neither is it
pretended to be so, in the often quoted _Tract_; it being only intimated
there, that the manner of performing it, as it is in that place represented
and described, is new.

_Lastly_, To rectifie the said Author's mistake, as if the instrument of
fetching up Water from the bottom of the Sea, were chiefly contriv'd, to
find out, Whether in some places of the Sea any _Sweet_ Water is to be met
with at the bottom: There will need no more, than to direct him to the Book
it self _Num._ 9. where p. 149. towards the end, the _First_ use of this
_Bucket_ is express'd to be, to know the _degrees of Saltness_ of the Water
according to its nearness to the top or bottom; or rather to know the
constitution of the Sea-water in several depths of several _Climates_,
which is a matter, much better to be found out by _Trial_, than
_Discourse_. Neither is it any where argued in that Book (as the _French
Journal_ insinuates) that, because sweet water is found at the Bottom of
the Sea of _Baharem_, therefore it _must_, but only that it _may_, be found
so elsewhere. And since the same _Journal_ admits, that those Sweet
water-springs, which yield the sweet water, that is found at the said
place, have been formerly on the _Continent_, far enough from the Sea,
which hath afterwards covered them. It will be, it is presumed, lawful to
ask, Why in many other places there may not be found the like? And besides,
how we do know, but that there may be in other parts, Eruptious of large
Springs at the bottom of the Sea, as well as there?

       *       *       *       *       *


Printed with Licence for _John Martyn_, and _James Allestry_, Printers to
the Royal-Society. 1666.

{231}

       *       *       *       *       *




_Num._ 14.

PHILOSOPHICAL
_TRANSACTIONS._

       *       *       *       *       *

_Munday_, _July_ 2. 1666.

       *       *       *       *       *

The Contents.

    _An Account of a _New_ kind of _Baroscope_, which may be call'd
    _Statical_; and of some Advantages and Conveniencies it hath above the
    _Mercurial_; communicated by Mr. _Boyle_. The Particular Observations
    of the Planet _Mars_, formerly intimated to have been made by Mr.
    _Hook_ in _February_ and _March_ last. Some Observations, made in
    _Italy_, confirming the former; and withall fixing the _Period_ of the
    said Planet's Revolution. Observations, lately made at _London_, of the
    Planet _Jupiter_: as also of _Saturn_. A Relation of a sad Effect of
    Thunder and Lightning. An Account of some Books, lately publish'd;
    _videl_. The Relations of divers Curious Voyages, by Mons. _Thevenot_:
    A Discourse about the Cause of the Inundation of the _Nile_, by Mons.
    _de la Chambre_, both _French_: De Principiis & Ratiocinatione
    Geometrarum, Contra Fastum Professerum Geometriæ, by Mr. _Hobbes_: King
    _Salomons_ Pourtraiture of Old Age, by_ J. Smith, M. D.

       *       *       *       *       *

_An Account of a _New_ kind of _Baroscope_, which may be called _Statical_;
and of some Advantages and Conveniencies it hath above the _Mercurial_:
Communicated, some while since, by the Honourable _Robert Boyle_._

[Sidenote: * See _Num. 11. p. 185. Phil. Transactions._]

As for the _New_ kind of _Baroscopes_, which, not long agoe, * I intimated
to you, that my haste would not permit me to give you an account off; since
your Letters acquaint me, that you still design a Communicating to the
{232} Curious as much Information, as may be, in reference to _Baroscopes_;
I shall venture to send you some Account of what I did but name (in my
former Letter) to you.

[Sidenote: * _The Scales here meant were before competent Eyewitnesses made
to turn manifestly with the thousandth part of a grain._]

Though by a Passage, you may meet with in the 19th and 20th Pages of my
_Thermometrical Experiments and Thoughts_, you may find, that I did some
years agoe think upon this New kind of Baroscope; yet the Changes of the
Atmosphere's Weight not happening to be then such, as I wish'd, and being
unwilling to deprive my self of all other use of the exactest Ballance *,
that I (or perhaps any man) ever had, I confess to you, that successive
avocations put this attempt for two or three years out of my thoughts; till
afterwards returning to a place, where I chanc'd to find two or three pairs
of Scales, I had left there, the sight of them brought it into my mind; and
though I were then unable to procure exacter, yet my desire to make the
Experiment some amends for so long a neglect, put me upon considering, that
if I provided a _Glass-buble_, more than ordinary large and light, even
such Ballances, as those, might in some measure perform, what I had tried
with the strangely nice ones above-mention'd.

I caused then to be blown at the Flame of a Lamp some _Glass-bubles_ as
large, thin and light, as I could then procure, and choosing among them,
one, that seem'd the least unfit for my turn, I counterpoised it in a pair
of Scales, that would loose their _Æquilibrium_ with about the 30th part of
a Grain, and were suspended at a Frame. I placed both the Ballance and the
Frame by a good Baroscope, from whence I might learn the present weight of
the Atmosphere. Then leaving these Instruments together; though the Scales,
being no nicer than I have express'd, were not able to shew me all the
Variations of the Air's weight that appear'd in the _Mercurial_ Baroscope,
yet they did what I expected, by shewing me variations no greater, than
alter'd the height of Quicksilver half a quarter of an Inch, and perhaps
much smaller than those: Nor did I doubt, that, if I had had either tender
Scales, or the means of supplying the experiment with convenient
accommodations, I should have {233} discerned far smaller Alterations of
the Weight of the Air, since I had the pleasure to see the Buble sometimes
in an _æquilibrium_ with the counterpoise; sometimes, when the Atmosphere
was high, preponderate so manifestly, that the Scales being gently stirr'd,
the Cock would play altogether on that side, at which the Buble was hung;
and at other times (when the Air was heavier) that, which was at the first
but the Counterpoise, would preponderate, and, upon the motion or the
Ballance, make the Cock vibrate altogether on its side. And this would
continue sometimes many daies together, if the Air so long retain'd the
same measure of gravity; and then (upon other changes) the Buble would
regain an _æquilibrium_, or a preponderance; so that I had oftentimes the
satisfaction, by looking first upon the _Statical_ Baroscope (as for
distinctions sake it may be call'd) to foretell, whether in the _Mercurial_
Baroscope the Liquor were high or low. Which Observations though they hold
as well in Winter, and several times in Summer (for I was often absent
during that season) as the Spring, yet the frequency of their Vicissitudes
(which perhaps was but accidental) made them more pleasant in the latter of
these seasons.

So that, the matter of Fact having been made out by variety of repeated
Observations, and by sometimes comparing severall of those new _Baroscopes_
together, I shall add some of those Notes about this Instrument, which
readily occur to my memory, reserving the rest till another opportunity.

And _First_, if the ground, on which I went in framing this _Baroscope_, be
demanded, the answer in short may be; 1. That, though the Glass-buble, and
the Glass-counterpoise, at the time of their first being weigh'd, be in the
Air, wherein they both are weigh'd, exactly of the same weight; yet they
are nothing near of the same bulk; the Buble, by reason of its capacious
cavity (which contains nothing but Air, or something that weighs less than
Air) being perhaps a hundred or two hundred times (for I have not
conveniency to measure them) bigger than the Metalline counterpoise. 2.
That according to a _Hydrostatical_ Law (which you know I have lately had
occasion to make out) If two Bodies of equal gravity, but unequal bulk come
to be weigh'd in another _Medium_, they will be no longer {234}
equiponderant; but if the new _Medium_ be heavier, the greater Body, as
being lighter in _Specie_, will loose more of its weight, than the lesser
and more compact; but if the new _Medium_ be lighter than the first, then
the bigger Body will outweigh the lesser; And this disparity, arising from
the change of _Medium's_, will be so much the greater, by how much the
greater inequality of bulk there is between the Bodies formerly
equiponderant. 3. That, laying these two together, I consider'd, that
'twould be all one, as to the effect to be produced, whether the Bodies
were weighed in _Mediums_ of differing gravity, or in the same _Medium_, in
case its (_specifick_) gravity were considerably alter'd: And consequently,
that since it appear'd by the _Baroscope_, that the weight of the Air was
sometimes heavier, and sometimes lighter, the alterations of it, in point
of gravity, from the weight, it was off at first counterpoising of the
Buble of it, would _unequally_ affect so large and hollow a Body, as the
Buble, and so small and dense a one, as a Metallin weight: And when the Air
by an increase of gravity should become a heavier _Medium_, than before, it
would buoy up the Glass more than the Counterpoise; and if it grew lighter,
than it was at first, would suffer the former to preponderate: (The
Illustrations and Proof can scarce be added in few words; but, if it be
desired, I may, God permitting, send you them at my next leasure:) And
though our English Air be about a thousand times lighter, than water, the
difference in weight of so little Air, as is but equal in bulk to a Buble,
seem'd to give small hopes, that it would be sensible upon a Ballance; yet,
by making the Buble very large and light, I supposed and found the Event, I
have already related.

_Secondly_, The hermetically seal'd Glass-buble, I employed, was of the
bigness of a somewhat large _Orange_, and weigh'd about 1. drachme and 10.
grains. But I thought it very possible, if I had been better furnish'd with
conveniencies (wherein I afterwards found, I was not mistaken) to make
(among many, that might be expected to miscarry) some, that might be
preferable to this, either for capacity or lightness, or both; especially
if care be taken, that they be not seal'd up, whilst they are too hot. For,
though one would think, that it were {235} advantagious to rarify and drive
out the Air as much as is possible, because in such seal'd Bubles the Air
it self (as I have elsewhere shewn) has a weight; yet this advantage
countervails not the inconvenience of being obliged to increase the weight
of the Glass, which when it includes highly rarified Air, if it be not
somewhat strong, will be broken by the pressure of the External Air, as I
have sufficiently tryed.

_Thirdly_, I would have tryed, whether the _Dryness_ and _Moisture_ of the
Air would in any measure have alter'd the weight of the Buble, as well as
the Variation of Gravity produced in the _Atmosphere_ by other causes; but
the extraordinarily constant absence of Fogs, kept me from making
Observations of this kind; save that one morning early, being told of a
mist, I sent to see (being my self in bed) whether it made the Air so heavy
as to buoy up the Buble; but did not learn, that that mist had any sensible
operation on it.

_Fourthly_, By reason of the difficulties and casualties, that may happen
about the procuring and preserving such large and light Bubles, as I have
been lately mentioning; it may in some cases prove a convenience to be
inform'd, That I have sometimes, instead of one sufficiently large Buble,
made use of two, that were smaller. And, though a single Buble of competent
bignes be much preferable, by reason that a far less quantity and weight of
Glass is requisite to comprise an equal capacity, when the Glass is blown
into a single Buble, than when it is divided into two; yet I found, that
the employing of two instead of one, did not so ill answer my
exspectations, but that they may for a need serve the turn instead of the
other; than which they are more easier to be procured; And if the Ballance
be strong enough to bear so much Glass, without being injur'd: by employing
two or a greater number of large Bubles, the effect may be more
conspicuous, than if only a single Buble (though a very good one) were
employed.

This instrument may be much improved by divers Accommodations, As

_First_, There may be fitted to the _Ansa_ (or Checks of the Ballance) an
Arch (of a Circle) divided into 15. or 20. deg. (more or less, according to
the goodness of the Ballance) that the Cock resting over against these
Divisions, may readily {236} and without Calculation shew the quantity of
the Angle, by which, when the scales propend either way, the Cock declines
from the Perpendicular, and the beam from its Horizontall parallelism.

_Secondly_, Those, that will be so curious, may, instead of the Ordinary
Counterpoise (of Brass) employ one of Gold, or at least of Lead, whereof
the _latter_ being of equal weight with Brass, is much less in Bulk, and
the _former_ amounts not to half its bigness.

_Thirdly_, These parts of the Ballance, that may be made of Copper or
Brass, without any prejudice to the exactness, will, by being made of one
of those Mettals, be less subject, than Steel, (which yet, if well hardned
and polish'd, may last good a great while) to rust with long standing.

_Fourthly_, Instead of the scales, the Buble may be hung at one end of the
Beam, and only a Counterpoise to it at the other, that the Beam may not be
burthen'd with unnecessary weight.

_Fifthly_, The whole instrument, if placed in a small Frame, like a square
Lanthorn with Glass-windows, and a hole at the top for the Commerce of the
internal and external Air, will be more free from dust, and irregular
agitations; to the latter of which, it will otherwise be sometimes
incident.

_Sixthly_, This instrument being accommodated with a light Wheele and an
Index (such as have been applyed by the excellent Dr. _Chr. Wren_ to open
Weather glasses, and by the ingenious Mr. _Hook_ to _Baroscopes_) may be
made to shew much more minute variations, than otherwise.

_Seventhly_, And the length of the Beam, and exquisitness of the Ballance,
may easily, _without_ any of the foregoing helps (and much more _with_
them) make the instrument far exacter, than any of those, I was reduced to
employ. And to these Accommodations divers others may be suggested by a
farther consideration of the nature of the thing, and a longer practice.

Though in some respects this _Statical_ Baroscope be inferior to the
_Mercurial_; yet in others it has its own advantages and conveniencies
above it.

And 1: It confirms _ad oculum_ our former Doctrine, that the falling and
rising of the _Mercury_ depends upon the varying weight of the Atmosphere;
since in this Baroscope it cannot {237} be pretended, that a _Fuga vacui_,
or a _Funiculus_, is the cause of the changes, we observe. 2. It shews,
that not only the Air has weight, but a more considerable one, than some
Learned men, who will allow me to have prov'd, it has some weight, will
admit; since even the variation of weight in so small a quantity of Air, as
is but equal in bulk to an _Orange_, is manifestly discoverable upon such
Balances, as are none of the nicest. 3. This _Statical_ Baroscope will
oftentimes be more parable, than the other: For many will finde it more
easie, to procure a good pair of Gold-scales, and a Buble or two, than a
long Cane seal'd, a quantity of _Quick-silver_, and all the other requisits
of the _Mercurial_ Baroscope; especially if we comprise the trouble and
skill, that is requisite to free the deserted part of the Tube from Air. 4.
And whereas the difficulty of removing the _Mercurial_ Instrument has kept
men from so much as attempting to do it, even to neighbouring places; the
Essential parts of the _Scale_-Baroscope (for the Frame is none of them)
may very easily in a little room be carried, whither one will, without the
hazard of being spoil'd or injur'd. 5. There is not in _Statical_
Baroscopes, as in the other, a danger of uncertainty, as to the goodness of
the Instruments, by reason, that in _these_ the Air is, in some more, and
in some less perfectly excluded; whereas in _those_, that consideration has
no place. (And by the way, I have sometimes, upon this account, been able
to discover by our new Baroscope, that an esteem'd _Mercurial_ one, to
which I compared it, was not well freed from Air.) 6. It being, as I
formerly intimated, very possible to discover _Hydrostatically_, both the
bigness of the Buble, and the Contents of the cavity, and the weight and
dimensions of the Glassie substance (which together with the included Air
make up the Buble,) much may be discover'd by this Instrument, as to the
Weight of the Air, _absolute_ or _respective_. For, when the _Quick-silver_
in the _Mercurial_ Baroscope is either very high, or very low, or at a
middle station between its greatest and least height, bringing the
_Scale_-Barometer to an exact _Æquilibrium_ (1 with very minute divisions
of a Graine,) you may, by watchfully observing, when the _Mercury_ is risen
or faln just an inch, or a fourth, of half an inch &c. and putting in the
like minute divisions of a Grain to the lighter Scale, till you have again
brought the Ballance to an {238} exquisit _Æquilibrium_; you may, I say,
determine, What known weight in the _Statical_ Baroscope answers such
determinate Altitudes of the ascending and descending Quick-silver in the
_Mercurial_. And if the Ballance be accommodated with a divided Arch, or a
Wheel and Index, these Observations will assist you for the future to
determine readily, by seeing the inclination of the Cock or the degree
mark'd by the Index, what pollency the Buble hath, by the change of the
_Atmospheres_ weight, acquired or lost. Some Observations of this nature I
watchfully made, sometimes putting in a 64^{th.} sometimes a 32^{th.}
sometimes a 16^{th.} and sometimes heavier parts of a Grain, to the lighter
Scale. But one, that knew not, for what uses those little papers were,
coming to a window, where my Baroscopes stood, so unluckily shook them out
of the Scales, and confounded them, that he robb'd me of the opportunity of
making the nice Observations I intended, though I had the satisfaction of
seeing, that they were to be made. 7. By this _Statical_ Instrument we may
be assisted to compare the _Mercurial_ Baroscopes of _several_ places
(though never so distant) and to make some Estimates of the Gravities of
the Air therein. As if, for instance, I have found by Observation, that the
Buble, I employ, (and one may have divers Bubles of several sizes, that the
one may repaire any mischance, that may happen to another) weigh'd just a
Drachme, when the _Mercurial_ Cylinder was at the height of 29½ inches
(which in some places I have found a _moderate_ altitude;) and that the
Addition of the 16th part of a gr. is requisite to keep the Buble in an
_Æquilibrium_, when the _Mercury_ is risen an 8th, or any determinate part
of an inch above the former station: When I come to another place, where
there is a _Mercurial_ Barometer, as well freed from Air as mine (for that
must be supposed) if taking out my _Scale_ instrument, it appeare to weigh
precisely a Drachme, and the _Mercury_ in the Baroscope there stand at just
29½ inches, we may conclude the Gravity of the Atmosphere not to be
sensibly unequal in both those two places, though very distant. And though
there be no Baroscope there, yet if there be an additional weight, as for
instance, the 16th part of a Grain requisite to be added to the Buble, to
bring the scales to an _Æquilibrium_, it will appear that the Air at this
second place is, at that time {239} so much heavier, than the Air of the
former place was, when the _Mercury_ stood at 29½ inches.

But in making such comparisons, we must not forget to consider the
Situation of the several places, if we mean to make Estimates not only of
the weight of the Atmosphere, but of the weight and density of the Air.
For, though the Scales wil shew (as has been said) whether there be a
difference of weight in the Atmosphere at the two places; yet, if one of
them be in a Vale or bottom, and the other on the top or some elevated part
of a Hill, it is not to be exspected, that the Atmosphere, in this latter
place, should gravitate as much, as the Atmosphere in the former, on which
a longer Pillar of Air does lean or weigh.

And the mention, I have made of the differing Situation of Places, puts me
in mind of something, that may prove another use of our _Statical_
Baroscope, and which I had thoughts of making tryal off, but was
Accidentally hindred from the opportunity of doing it. Namely, that by
exactly poysing the Buble at the foot of a high Steeple or Hill, and
carrying it in its close Frame to the top, one may, by the weight requisite
to be added to Counterpoise there to bring the Beam to its Horizontal
position, observe the difference of the weight of the Air at the bottom,
and at the top; and, in case the Hill be high enough, at some intermediate
Stations. But how far this may assist men, to estimate the _Absolute_ or
_Comparative_ height of Mountains, and other elevated Places; and what
other Uses the Instrument may be put to, when it is duly improved; and the
Cautions, that may be requisite in the several cases, that shall be
proposed, I must leave to more leasure, and farther Consideration.

       *       *       *       *       *

_The Particulars of those Observations of the Planet _Mars_, formerly
intimated to have been made at _London_ in the Months of _February_ and
_March_ A._ 1665/6.

To perform, what was promised _Num._ 11. of these Papers, _pag._ 198; 'tis
thought fit now to publish the Particular Observations, concerning the
spots in _Mars_, and their motion, as they were made with a 36 foot
Telescope, and produced in {240} writing before the _Royal Society_, the 28
_March_ 1666. by Mr. _Hook_, as follows;

Having a great desire (saith he) to observe the Body of _Mars_, whilst
_Acronycal_ and _Retrograde_ (having formerly with a Glass of about 12.
foot long, observ'd some kind of Spots in the Face of it,) though it be not
at present in the _Perihelium_ of its Orbe, but nearer its _Aphelium_, yet
I found, that the Face of it, when neer its Opposition to the Sun (with a
Charge, the 36. foot-glass, I made use off, would well bear) appear'd very
near as big, as that of the Moon to the _naked_ eye; which I found, by
comparing it with the Full Moon, near adjoyning to it, _March_ 10.

But such had been the ill disposition of the Air for several nights, that
from more than 20. Observations of it, which I had made since its being
_Retrograde_, I could find nothing of satisfaction, though I often
imagin'd, I saw Spots, yet the _Inflective veins_ of the Air (if I may so
call those parts, which, being interspers'd up and down in it, have a
greater or less Refractive power, than the Air next adjoyning, with which
they are mixt) did make it so confus'd and glaring, that I could not
conclude upon any thing.

On the third of _March_, though the Air were still bad enough yet I could
see now and then the Body of _Mars_ appearing of the form A: which I
presently described by a _Scheme_; and about 10. minutes after, as exactly
representing what I saw through the Glass, as I could, I drew the _Scheme_
B. This I was sufficiently satisfied (by very often observing it through
the Tube, and changing my Eye into various positions, that so there might
be no kind of Fallacy in it) could be nothing else, but some more _Dusky_
and _Spotted_ parts of the Face of this Planet.

_March_ 10. finding the Air very bad, I made use of a very shallow
Eye-glass, as finding nothing _Distinct_ with the greater _Charge_; and saw
the appearance of it as in C, which I imagin'd, might be the Representation
of the former Spots by a lesser charge. About 3 of the Clock the same
morning, the Air being _very bad_ (though to appearance _exceeding clear_,
and causing all the Stars to twinckle, and the minute Stars to appear very
thick) the body seem'd like _D_; which I still suppos'd to be {241} the
Representation of the same Spots through a more confused and glaring Air.

But observing _March_ 21. I was surprised to find the Air (though not so
clear, as to the appearance of small Stars) so _exceeding transparent_, and
the Face of _Mars_ so very well _defined_, and round, and distinct, that I
could manifestly see it of the shape in E. about half an hour after Nine at
night. The _Triangular_ spot on the right side (as it was inverted by the
Telescope, according to the appearances, through with all the preceeding
_Figures_ are drawn) appear'd very black and distinct, the other towards
the left more dim; but both of them sufficiently plain and defin'd. About a
quarter before 12. of the Clock the same night, I observ'd it again with
the same Glass, and found the appearance exactly, as in F; which I imagin'd
to shew me a _Motion_ of the former triangular spot: But designing to
observe it again about 3. of the Clock the same Morning, I was hindred by
cloudy weather.

But _March_ 22. about half an hour after 8. at night, finding the same
Spots in the same posture, I concluded, that the preceeding Observation was
only the appearance of the same Spots at another height and thickness of
the Air: And thought my self confirm'd in this Opinion, by finding them in
much the same posture, _March_ 23. about half an hour after 9. though the
Air was nothing so good as before.

And though I desired to make Observations, about 3. of the Clock those
mornings; yet something or other interven'd, that hindred me, till _March_
28. about 3 of the Clock, the Air being light (in weight) though moist and
a little hazy; when I plainly saw it, to have the form, represented in I;
which is not reconcileable with the other Appearances, unless we allow a
_Turbinated_ motion of _Mars_ upon its Center: Which, if such there be,
from the Observations made _March_ 21. 22. and 23. we may guess it to be
once or twice in about 24. hours unless it may have some kind of
_Librating_ motion; which seems not so likely. Now, whether certainly so or
not, I shall endeavour, as oft as I have opportunity, further to observe.

[Illustration]

A particular direction to the _Figures_ mentioned in the precedent
discourse.

A. _March _3^{d.} 00^{h.} 20^{m.}_ in the morning: the Air having many
{242} inflecting parts dispersed up and down in it; by the _Wheel
Barometer_, heavy,_

B. _Another Scheme, which I drew from my Observation, about 10. minutes
after, the same morning. Both these were observed with a very deep
Eye-glass._

C. _March_ 10^{d.} 00^{h.} 20^{m.} _in the morning: the Air heavy and
inflective. Use was made of a shallow or ordinary Charge._

D. _March_ 10^{d.} 3^{h.} 00^m _in the Morning; the Air very heavy and
Inflective, which made it glare and radiate, and be more confused, than
about 3. hours before. A shallow Charge._

E. _March_ 21^{d.} 9½^{h.} _post merid; the Air light (in weight) and
clear, without inflecting parts; the Face appear'd most distinctly of this
Forme. A shallow Charge._

F. _March_ 21^{d.} 11¾^{h.} _post merid; the Air continuing very light and
clear, without inflecting vapours. A shallow Charge._

G. _March_ 22^{d.} 8½^{h.} _post mer. the Air clear, with few inflecting
veins in it, and indifferent light. A shallow Charge._

H. _March_ 23^{d.} 9½^{h.} _post mer. the Air pretty light, but moist, and
somewhat thick and hazy, but seem'd to have but few veins, or inflecting
parts._

I. _March_ 28^{d.} 3^{h.} _p. m. much the same kind of Air with that of
March 23; light, moist, and a little hazy, with some very few veins._

       *       *       *       *       *

_Observations made in _Italy_, confirming the former, and withall fixing
the _Period_ of the Revolution of _Mars_._

These Observations we shall summarily present the Curious in these parts
with, as they were lately presented (by Letter from his Excellency the
Ambassadour of _Venice_, now residing at the Court of _France_) to the
_Royal Society_, in some printed sheets of Paper, entituled, _MARTIS, circa
Axem proprium Revolubilis, Observationes, BONONIÆ à JO. DOMINICO CASSINO
habitæ;_ come to hand _June_ 3. 1666.

In these Papers the Excellent _Cassini_ affirms;

1. That with a _Telescope_ of 24. _Palmes_, or of about 16 _Foot_, wrought
after S. _Campani's_ way, he began to observe _February_ 6. 1666 (st.n.) in
the morning, and saw two dark Spots in the _first_ Face of _Mars._ {243}

2. That with the same Glass he observ'd _Febr._ 14/24. in the Evening, in
the _other_ Face of this Planet, two other Spots, like those of the first,
but bigger.

3. That afterwards continuing the Observations, he found the Spots of these
two Faces to turn by little and little from _East_ to _West_, and to return
at last to the same situation, wherein he had seen them first.

4. That S. _Campani_, having also observ'd at _Rome_ with Glasses of 50.
_Palmes_ or about 35 _Foot_, likewise of his own contrivance, had seen in
the same Planet the same _Phenomena_.

5. That sometimes he hath seen, during the same night, the two Faces of
_Mars_, one, in the Evening, the other in the Morning.

6. That the Motion of these Spots in the inferior part of the apparent
Hemisphere of _Mars_, is made from _East_ to _West_, as that of all the
other Celestial Bodies, and is peform'd by Parallels, that decline _much_
from the _Equator_, and _little_ from the _Ecliptick_.

7. That the Spots return the next day to the same situation, 40. minuts
later, than the day before; so that in every 36. or 37. daies, about the
same hour, they come again to the same place.

8. He promises shortly to give us the particular _Tables_ of this Motion
and of its Inequalities, together with the _Ephemerides_ themselves.

9. He represents, that some other _Astronomers_ have also made at _Rome_
several Observations of these Spots of _Mars_, from _March 14/24._ to
_March 20/30._ with Glasses, wrought by _Eustachio Divini_, of 25. and 45.
Palmes; Which Spots he makes little differing from his own, of the first
Face; as will by and by appear, by the direction to the _Schemes_.

10. But he adds, that those other _Roman_ Astronomers, that have observ'd
with _Divini's_ Glasses, will have the Conversion of _Mars_ to be
performed, not in 24 h, 40 m. (as he maintains it is) but in about 13 h.

11. And to evince, that they are mistaken in these Observations of theirs;
he alledges, That they assure that the Spots, which they have seen in this
Planet, (by an _Eustachian_ Telescope) the 20/30 of _March_, were small,
very distant from one another, remote from the middle of the Disk, and the
_Oriental_ Spot was less, than the _Occidental_ (as is represented by the
Fig. O; like that of the first Face of _Mars_.) whereas, on the contrary,
{244} He (_Cassini_) pretends to evidence by his Observations, made at the
same time at _Bononia_, that, the same day and hour, those Spots were very
large, neer one another, in the midst of the Disk, the Oriental bigger than
the Occidental (as appears by _Fig._ P, which is that of the second Face of
_Mars_.)

12. Besides, he declares, that those _Astronomers_ were too hasty, in
determining, after 5 or 6 Observations only, in how much time _Mars_
finish's his Revolution; and denies it to be perform'd in 13 hours: adding,
that, though Himself had observ'd for a much longer time, than they; yet he
durst not for a great while define, Whether _Mars_ made but _one_ Turn in
24 hours 40 minuts or _two_; and that all, that he could, for a long time
affirm, was onely this, that after 24 h. 40 m. this Planet appear'd in the
same manner he did before.

13. But since those first Observations, He affirms to have found cause to
determine, that the Period of this Conversion is made in the said space of
24 h. 40 m; and not oftner than once within that time; Alledging for proof;

1. That, whereas _Febr._ 6. (st.n.) he saw the Spots of the first Face of
_Mars_, moving from eleven of the Clock in the night, until break of day,
they appear'd not afterwards in the Evening after the rising of that Planet
(witness several intelligent persons, which he names, that were present at
the Observations) Whence he infers, that after 12 hours and 20 minuts, the
same Spots did not come about; since that the same, which in the morning
were seen in the middle, upon the rising of _Mars_; after 13 or 14 hours,
might have appear'd neer the Occidental Limb. But, because he might be
imposed upon by Vapors, whilst _Mars_ was yet so neer the _Horizon_, he
gives this other determination, _vid._

2. Whereas he saw the first Face of _Mars_ the 6 of _February_ at 11 of the
clock of the night following; he did not see the same after 18 daies at the
same hour; as he ought to have done, if the Period were absolved in the
space of 12 h. 20 m.

[Illustration]

3. Again, whereas he saw _Febr._ 24. in the Evening, the other Face of
_Mars_, he could not see the same, the 13. and 15. day of _March_, to wit
after 17 and 19 days; as he should have done, if the Revolution were made
in the newly mention'd time.

4. Again, whereas the 27. of _March_ in the Evening he saw {245} the second
Face of _Mars_, he could not see it the 14. and 16. of _April_.

From all which Observations he Judges it to be evident, that the Period of
this Planets Revolution is not perform'd in the space of 12. hours 20,
minutes, but in about 24 hours 40 minutes; more exactly to be determin'd by
comparing distant Observations: And that those who affirm the former, must
have been deceived by not well distinguishing the two Faces, but that
having seen the second, taken it for the first.

All which he concludes with this Advertisement, that, when he defines the
time of the Revolution of _Mars_, he does not speak of its _Mean_
Revolution, but onely of that, which he observ'd, whilst _Mars_ was
opposite to the Sun; which is the shortest of all.

    _The Figures of the _Principal_ Observations, represented in the Book
    here discoursed of, may be seen in the annexed _Scheme_; _videl.__

K. _One of the Faces of _Mars_, as S. _Cassini_ observed it _March 3.
(_st.n._) 1666_ in the Evening, with a Glass of 24 Palmes._

L. _The other Face, as he saw it _Febr. 14/24_ in the Evening._

M. _The first Face, as S. _Campani_ saw at Rome, _March 3. 1666_. in the
Evening, with a Glass of 50 Palmes._

N. _The second Face, as the same _Campani_ observed it _March 18/28_. in
the Evening._

O. _The figure of _Mars_ as it was seen at _Rome_ by a Telescope of
_Divini_ of 45 Palmes, _March 20/30_._

P. _The Figure of the said Planet, as it was seen the same day and hour at
Bononia by _Cassini_; being that of the second Face._

       *       *       *       *       *

_Some Observations lately made at _London_ concerning the Planet
_Jupiter_._

These, as they were made, so they were imparted, by Mr. _Hook_, as follows:

[Illustration]

A. 1666, _June_ 26. between 3. and 4. of the Clock in the morning, I
observed the Body of _Jupiter_ through a 60 foot-glass, and found the
apparent Diameter of it through the Tube, to be somewhat more than 2.
degrees, that is, about four {246} times as big, as the Diameter of the
_Moon_ appears to the _naked_ Eye. I saw the Limb pretty round, and very
well defin'd without radiation. The parts of the _Phasis_ of it had various
degrees of Light. About a and f, the _North_ and _South_ poles of it (in
the _Fig Q._) 'twas somewhat darker, and by degrees it grew brighter
towards b. and e, two Belts or Zones; the one of which (b) was a small dark
_Belt_ crossing the Body Southward; Adjoyning to which was a smal Line of a
somewhat lighter part; and below that again, Southwards, was the great
black _Belt c_. Between that, and e, the other smaller black Belt, was a
pretty large and bright _Zone_; but the middle d, was somewhat darker than
the edges. I perceiv'd about 3^{h.} 15^{m.} near the middle of this, a very
_dark round Spot_, like that represented at g, which was not to be
perceiv'd about half an hour before: And I observed it, in about 10.
minutes time to be gotten almost to d, keeping equal distance from the
_Satelles h_, which moved also Westwardly, and was joyn'd to the Disk at i,
at 3^{h.} 25^{m.} After which, the Air growing very hazy, and (as appeared
by the _Baroscope_) very light also (in weight) I could not observe it: So
that it was sufficiently evident, that this black Spot was nothing else,
save the shadow of the _Satelles h_, Eclipsing a part of the Face of
Jupiter. About two hours before, I had observed a large darker spot in the
bigger _Belt_ about k, which in about an hour or little more (for I did not
exactly observe the time, nor draw the _Figure_ of it) moving Westwards,
disappear'd. About a week before, I discover'd also, together with a Spot
in the _Belt c_, another Spot in the _Belt e_, which kept the same way and
velocity with that of the _Belt c_. The other three _Satellites_ in the
time of this Eclipse, made by the _Satelles_, were Westwards of the Body of
_Jupiter_; appearing as bright through the Tube, as the Body of _Jupiter_
did to the naked Eye, and I was able to see them longer through the Tube,
after the day-light came on, than I was able to see the Body of _Jupiter_
with my naked eye.

       *       *       *       *       *

_A late Observation about Saturn made by the same._

[Illustration]

_June_ 29 1666. between 11. and 12. at night I observed the Body of
_Saturn_ through a 60. foot Telescope, and found it {247} exactly of the
shape represented in the _Figure_ R. The _Ring_ appear'd of a somewhat
brighter Light than the _Body_; and the black lines a a, crossing the Ring,
and b b crossing the Body (whether Shadows or not, I dispute not) were
plainly visible: whence I could manifestly see, that the _Souther_-most
part of the Ring was on _this_ side of the Body, and the _Northern_ part,
behind, or covered by the Body.

       *       *       *       *       *

_A Relation of a sad effect of Thunder and Lightning:_

This Relation was written by that worthy Gentleman, _Thomas Neale_ Esquire,
(the then _High Sheriff_ of the County of _Hampshire_, when this disaster
hapned) to a Friend of his in _London_, as follows;

On the 24 of _January_ 1665/6, one Mr. _Brooks_ of _Hampshire_, going from
_Winchester_ towards his house near _Andover_ in very bad Weather, was
himself slain by Lightning, and the Horse, he rode on, under him. For about
a mile from _Winchester_ he was found with his Face beaten into the ground,
one leg in the stirrup, the other in the Horses mane; his Cloaths all burnt
off his back, not a piece as big as a handkerchief left intire, and his
hair and all his body singed. With the force, that struck him down, his
nose was beaten into his face, and his Chin into his Breast; where was a
wound cut almost as low, as to his Navil; and his cloaths being, as
aforesaid, torn, the pieces were so scatter'd and consum'd, that not enough
to fill the crown of a hat could be found. His gloves were whole, but his
hands in them sing'd to the bone. The hip-bone and shoulder of his Horse
burn't and bruised; and his saddle torn in little pieces. This was what
appear'd to the Coroners inquest, and so is likely to be as near truth, as
any is to be had.

_So far this Letter_: Which, if it had come soon enough to the hands of the
_Publisher_, would have been joyned to a like _Relation_, inserted in the
next foregoing Papers (_Num._ 13.) of an accident hapn'd at a later time.
With both which may be compared the Account, formerly published in Latin by
the Learned Dr. _Charleton_, concerning the Boy, that was {248}
Thunder-struck near _Nantwich in Cheshire;_ the Title of the Book being
_Anatome Pueride Cælo tacti_: such Relations, when truly made, well
deserving to be carefully recorded for farther consideration.

       *       *       *       *       *

_Of some Books lately publish't._

_RELATIONS OF DIVERS CURIOUS VOYAGES_, by _Mons. Thevenot_, the third
_Tome_, in _French_. This Book contains chiefly, the Ambassie of the
_Dutch_ into _China_, translated out of the Dutch manuscript: A
Geographical description of _China_, translated out of a Chinese Author by
_Martinius_: And the Account, which the Directors of the Dutch East-India
Company made to the States General, touching the state of affairs in the
East-Indies, when their late Fleet parted from thence. To touch some things
of a _Geographical_ and _Philosophical_ nature, contained therein, we shall
take notice;

1. How the Kingdom of _China_ is peopled; there being according to the best
computation (which is there made with singular care) above 58 millions of
Men, not counting Magistrates, Soldiers, Priests, Eunuchs, Women and
Children; so that it may not be altogether strange, if one should affirm,
there were 200 millions of people, of all sorts, in that Kingdom.

2. That _Catay_ is nothing else, but the _Six_ Northern Provinces of
_China_, separated from the other _Nine_, by the great River _KIANG_; and
that the City _Cambalu_ is the same with that of _Peking_; the _Tartars_,
who carry every three years their Tribute to the Emperor of _China_,
constantly calling the said Provinces and City by those names of _Catay_,
and _Cambalu_.

3. That _China_ is so well furnisht with Rivers, and cut Channels, that men
may go from the most Southern to the most Northern part thereof by water,
except one daies journey; as the Dutch Ambassadours did, embarking at
_Canton_, which is 23d. 48m. Northern Latitude, and landing at _Peking_,
which is about 40d; having only travell'd one daies journey over some
Mountains of the Province _Kiamsi_.

4. That the people of _China_ are exceeding industrious {249} Husbandmen
making, among other waies of improving their soile, great use of Flouding.

5. That the _Physicians_ of _China_ do cure Sicknesses with much ease, and
in a short time: That they have very ancient Books of the nature and
vertues of Herbs, Trees and Stones: That their Modern Physicians (as well
as their Ancient ones did) write of the Prognosticks, Causes, Effects, &c.
of Diseases. That their Remedies consist for the most part of _Simples_ and
_Decoctions_, _Cauteries_, _Frictions_; without the use of _Bloud letting:_
That they have such an excellent skill and method in feeling the _Pulse_,
that by the means thereof they discover even the most latent causes of
Diseases; taking a good half hour, when they visit a Patient, in feeling
and examining his Pulse: That they prescribe much the use of _The_; and the
drinking alwayes warme, whatever they drink: To the custome of both which
it's imputed, that the inhabitants of _China_ do spit very little, nor are
subject to the Stone or Gout: That they prise highly the Root _Ginseng_, as
an extraordinary Restorative and Cordiall, recovering frequently with it
agonizing persons; one pound of it being paid with 3 pounds of silver. As
for their _Chymists_, (of which they have also good store) they go beyond
ours, promising not only to make Gold, but to give Immortality.

6. That their _Nobility_ is raised from Learning and Knowledge, without
regard to Bloud or Parentage, excepting the Royall Family.

7. That in _CHEKIAN_, a maritime Province, whence is the shortest cut of
_China_ to _Japan_, is the best and plentifullest _Silk-trade_ in the
world: And that there every year the Mulberries are cutt, and kept down,
that they grow not into Trees for the easier gathering of the Leaves, there
being a _double_ Silk-harvest in that Country, as there is in severall
other parts of the East-indies; (both which there is hope, will shortly be
imitated in _Virginia_.)

8. That the way of making _Porcelane_ is this: (_Which is the rather
inserted here, because it agrees so well with an Account, we received a
while since from a very Curious and intelligent Person of Amsterdam._)
There is in the Province of _Nankin_ a Town, call'd {250} _Goesifols_
whence they draw the Earth for _Porcelaine_, which is found between the
Rocks of Mountains. This Earth they beat very small, and stamp it to a very
fine Powder, and then put it into Tubs fill'd with water; where the finest
part sinks to the bottom. Afterwards 'tis kneaded in the form of small
Cubes, of the weight of about 3. _Catti_ (a _Catti_ being 20 Ounces.) These
pieces thus wrought are sold to the people, that commonly in great numbers
fetch them, coming from the Town _Sintesimo_ (otherwise _Jontiou_) in the
Province of _Kiansy_, being about 50 miles distant from _Wotsing_, neer the
City _KIANSY_; which people transport them to their homes, and there bake
them in this manner: They heat their Ovens well, for the space of 15 daies
successively, and then keep them so close, that no Air may get in; and
after 15 _other_ daies are pass'd, they open the Oven in the presence of an
Officer, who takes every fifth vessel of each fashion for the service of
the Emperor: Which done, the rest is sold to those of _Ucienien_, whence it
is transported all over the Country. So that the Earth is not prepared, in
_Nankin_, where 'tis found, because the people of that Province have not
the skill of working it, as the other above-mention'd; who also alone have
the Art of coloring it, which they keep as a great Secret, not teaching it
to any, but their Children and next Kindred.

9. That _Musk_ is nothing else, but the Testicles of a Beast like a Dear,
found in the Province of _Honan_; and that, when tis good and unmixt, as it
comes from the Animal, they sell it even in _Nankin_ and _Pekin_, for 30.
or 35. _Teyls_ (that is, about so many Crowns) the _Catti_.

Many other curious informations might be borrow'd from this Author,
concerning the Customs, Studies, Exercises of the _Chinese_; of the number
of the people of each Province; of the Natural productions of the Earth and
Rivers there; of the Structure and Antiquity of their Wall; of the
Magnificence of their Porcelain Tower &c.; but, remitting for these things
to the Book it self, we shal only add a piece of Oeconomy, used by the
_Holland_-Merchants in their Commerce with _China_, which is, that they dry
abundance of Sage-leaves, role them up, and {251} prepare them like _The_,
and carrying it to _China_, as a rare drogue, get for one pound of it,
fourtimes as much _The_.



_A DISCOURSE ABOUT THE CAUSES OF THE INUNDATION OF THE NILE_, in _French_.
The Author of this Book is Monseiur _dela Chambre_, who being perswaded
from several Circumstances, that accompany the Overflowing of this River,
that it cannot proceed from Rain, ventures to assign for a Cause of _it_,
and of all the other effects that happen at the time of its swelling, the
_Niter_, wherewith that water abounds.

The discourse having six parts, the Author endeavours to shew in the

_First_, that the Waters of the _Nile_ are Nitrous, explicating the Nature
of Salt, and Saltpeter, and imputing the fertility of the Earth, as well us
the fecundity of Animals, to Salt. Where he shews, that all things, that
serve to improve Land, are full of Salt; and that 'tis observ'd, that grain
steep'd in Vrine, before sowing, rises sooner, and becomes fuller and
stronger, than else. Adding, that that, which renders the Seed of Animals
prolifick, is, that one of the _Spermatick_ veins hath its Origine from the
_Emulgent_, through which the Nitrous and Saline Serosities, that discharge
themselves into the Kidneys and Bladder, do pass.

In the _Second_, he examins, what is Fermentation, and how 'tis perform'd;
affirming, that, what thrusts forth Plants in the Spring, is, that the
Earth being fermented by the _Niter_, it harbours, the Nitrous spirits
insinuate themselves into their Pores.

In the _Third_ he treats of all the Circumstances, observable in the
Inundation of the Nile. 'Tis affirm'd, that 3 or 4 days before that River
begins to overflow, all its water is troubled: that then there falls a
certain Dew, which hath a fermenting vertue, and leavens a Paste exposed to
the Air: that the Mud, which has been drawn out of the water, grows
heavier, when the overflowing begins, then it was before, and that by the
increase of the weight of that Mud, they judge of the greatness of the
approaching inundation. The Author pretends, that {252} the Niter, which
the _Nile_ is stored with, is the cause of all these strange effects, and
of many others, by him alledged. For, _saith he_, when the Nitre is heated
by the heat of the Sun, it ferments, and mingling with the water, troubles
it, and swells it, and makes it pass beyond its banks; after the same
manner, as the Spirits in new Wine render it troubled, and make it boyle in
the vessel. And it seems not likely to him, that the Mud, found in the
_Nile_, should come a far off; for then it would at last so raise the banks
of this River, that it would not be able to overflow them any longer.
Whereas 'tis more than 2000 years, that the banks thereof are not grown
higher, there being now requisite but 16. cubits for overflowing the Land,
no more than there was in the time of _Herodotus_. Which shews, _saith he_,
that this Mud is nothing but a volatil _Niter_, which exhaling, doth not
increase the Earth. As for the _Ægyptian_ Dew, and the increase of the
weight of the Mud, he adscribes them to the same Cause. For the spirits of
Nitre abounding in the _Nile_, when raised into the Air with the vapors,
that exhale continually from this River, there is made out of their
mixture, a Dew, that refreshes the Air, makes sickness to cease, and
produces all those admirable effects, that make the _Ægyptians_ wish for it
so passionately. And the same spirits of Niter, being joyned to the Paste,
and to the Mud, raise the one, and augment the weight of the other. That,
which Mr. _Buratini_ observes, that at the time of this inundation, the
Niter-pits of the neighboring places vomit out liquid Niter, and that one
may see issue out of the Earth abundance of Chrystals of Nitre, is alledged
to fortify this conjecture; Which is yet more confirm'd by the Fertility,
communicated to the Earth by the Mud of this River. For, plants do grow
there in such abundance, that they would choak one another, if it were not
remedied by throwing Sand upon the Fields; insomuch that the _Ægyptians_
must take as much pains to spread Sand to lessen the fatness of their Land,
as other Nations do, to spread dung or other manure upon theirs to increase
the fatness.

In the _Fourth_ and _Fifth_, the Author undertakes to prove, that all those
strange effects cannot be attributed to Rain or Snow, {253} and that the
overflowing of the _Nile_ always happens at a certain day.

In the _Last_, he alledges some Relations, serving to confirm his Opinion;
Which are too long here to insist upon.



_DE PRINCIPIIS ET RATIOCINATIONE GEOMETRARUM, Contra Fastum Professorum
Geometriæ;_ Authore _Thoma Hobbes_. It seems, that this Author is angry
with all Geometricians, but himself; yea he plainly saith in the dedication
of his Book, that _he invades the whole Nation of them_; and unwilling, it
seems, to be call'd to an account for doing so; He will acknowledge no
judge of _this_ Age; but is full of hopes, that posterity will pronounce
for him. Mean while he ventures to advance this _Dilemma_; _Eorum qui de
iisdem rebus mecum aliquid ediderunt, aut solus insanio Ego, aut solus non
insanio; tertium enim non est, nisi (quod dicet forte aliquis) insaniamus
omnes._ Doubtless, one of these will be granted him.

As to the Book it self, he professes, that he doth not write it against
_Geometry_, but _Geometers_; and that his design in it is, to shew, That
there is no less uncertainty and falsity in the writings of
_Mathematicians_, than there is in those of _Naturalists_, _Moralists_,
&c., though he judges, that _Physicks_, _Ethicks_, _Politicks_, if they
were well demonstrated, would be as certain as the _Mathematicks_.

Attacking the Mathematical Principles as they are found in Books, and
withall some Demonstrations, he takes to task _Euclid_ himself, instead of
all, as the Master of all Geometricians, and with him his best interpreter,
_Clavius_, examining in the _First_ place, the _Principles_ of _Euclid_:
_Secondly_, Declaring false, what is superstructed upon them, whether by
_Euclid_, or _Clavius_, or any _Geometer_ whatsoever that hath made use of
those or other (as he is pleased to entitle them) _false_ Principles.
_Thirdly_, Pretending, that he means so to combat all, both Principles and
Demonstrations, undertaken by him, as that he will substitute better in
their room, least he should seem to undermine the Science it selfe. {254}

The particulars, which he undertakes to reform, are,

  _Punctum._
  _Linea._
  _Terminus._
  _Linea Recta._
  _Superficies._
  _Superficiei Termini._
  _Superficies Plana,_
  _Angulus_ (Where he is large upon the _Angulus Contactus._)
  _Petitio prima Elem. 1. Euclidis._
  _Ratio._
  _Radix & Latus._
  _Prop. 16. El. 3._
  _Dimensio Circuli._
  _Magnitudo Circuli Hugeniana._
  _Sectio Anguli._
  _Ratio, quam habet recta composita ex Radio & Tangente 30. grad, ad
      Radium ipsum._
  _Propos. 47æ. Elem. 1. Demonstratio._
  _Addita est Appendix de Mediis proportionalibus in genere._



_KING SALOMONS POUTRAITURE OF OLD AGE_; by _John Smith_, M.D. This Treatise
being a _Philosophical_ Discourse, though upon a _Sacred_ Theme, may
certainly claim a place among _Philosophical_ Transactions. Not here to
mention the many other learned Notes, this Worthy Author gives upon that
Hieroglyphical Description of Old Age, made by that Royal Pen-man of
_Ecclesiastes_, cap. 12. We shall onely take notice of that surprizingly
Ingenious one, there to be met with, concerning the Antiquity of the
Doctrine of the _Blood's Circulation_: King _Salomon_, who lived neer 2700
years agoe, using such expressions, as may, to a considering Reader, very
probably denote the same Doctrine, which the Sagacious Dr. _Harvey_ has of
late years so happily brought to light, and introduced into all the most
Ingenuous Societies of Learned men: The _Pitcher_, mention'd in the quoted
place, being Interpreted for the _Veines_, and the _Fountain_ for the
_Right Ventricle of the Heart_, as the _Cistern_ for the _Left_; the
_Wheele_, there spoken off, manifestly importing a _Circulation_, made by
the _Great Artery_ with its Branches, the principal Instrument thereof.

       *       *       *       *       *


Printed with Licence for _John Martyn_, and _James Allestry_, Printers to
the Royal Society. 1666.

{255}

       *       *       *       *       *




_Num._ 15.

PHILOSOPHICAL
_TRANSACTIONS._

       *       *       *       *       *

_Wednesday_, _July_ 18. 1666.

       *       *       *       *       *

The Contents.

    _A new Experiment, shewing, How a considerable degree of Cold may be
    suddenly produced without the help of _Snow_, _Ice_, _Haile_, _Wind_,
    or _Niter_, and that at any time of the year. An Account of two Books,
    lately printed in _London_; whereof the one is entituled, _EUCLIDIS
    ELEMENTA GEOMETRICA, novo ordine ac Methodo demonstrata_; the Author
    _Anonymus_. The other, _THE ENGLISH VINE-YARD VINDICATED_, by _JOHN
    ROSE_._

       *       *       *       *       *

_A new Frigorifick Experiment shewing, how a considerable degree of _Cold_
may be suddenly produced without the help of _Snow_, _Ice_, _Haile_,
_Wind_, or _Niter_, and that at any time of the year._

This subject will it self, 'tis presumed, without any other _Preamble_,
speak the Cause, why this present Paper is publish't at this (unusual) time
of the Month: though, by the by, it may not be amiss to add on this
occasion, that the Publisher of these _Tracts_ never meant so to confine
himself to a _Set_ time, as not to retain the Liberty of taking any other,
when there is occasion. And there being one given him, before another Month
is come in, he does without any scruple or delay comply therewith,
presenting the Curious with an Experiment which he thinks is both
seasonable, and will not be unwellcome to them; furnish't out of the Ample
Magazin of that Philosophical Benefactor, the Noble Mr. _Boyle_; Concerning
which, thus much is further thought requisite to intimate on this occasion,
that it, and some others of the same Gentlemans, that have been, and may
be, mentioned in the _Transactions_, belong to certain Treatises, the
Author hath lying by him; but that yet he denys not {256} to communicate
them to his Friends, and to allow them to dispose thereof, upon a hope,
that equitable Readers will be ready to excuse, if hereafter they should
appear also in the Treatises they belong to, since he consents to this
Anticipation, but to comply with those, that think the imparting of real
and practical Experiments, may do the Publick some Service, by exciteing
and assisting mens Curiosity in the interim.

As for the Experiment, you saw the other day at my Lodgings, though it
belongs to some Papers about _Cold_, that (you know) could not be
Publish't, when the rest of the _History_ came forth, and therefore was
reserved for the next _Edition_ of that Book; yet the Weather having been
of late very hot, and threatning to continue so, I presume, that to give
you here in compliance with your Curiosity an Account of the Main and
Practical part of the Experiment, may enable you to gratify not onely the
Curious among your Friends, but those of the Delicate, that are content to
purchase a Coolness of Drinks at a somewhat chargeable rate.

You may remember, that the Spring before the last, I shew'd you a
particular Account of a way, wherein by a certain substance obtain'd from
_Sal Armoniack_, I could presently produce a considerable degree of _Cold_,
and that with odd Circumstances, without the help of _Snow_, _Ice_, _Niter_
&c. But that Experiment being difficult and costly enough, and design'd to
afford men _Information_, not _Accomodations_, I afterwards tryed, what
some more cheap and facile mixtures of likely Bodies with _Sal Armoniack_
would do towards the Production of Cold, and afterwards I began to
consider, whether to that purpose alone (for my first experiment was
design'd to exhibite other _Phænomena_ too) those mixtures might not
without inconvenience be omitted: and I was much confirm'd in my
conjecture, by an accident, which was casually related to me by a very
Ingenious Physician of my acquaintance, but not to be repeated to you in
few words, though he complain'd, he knew not what to make of it.

Among the several ways, by which I have made infrigidating Mixtures with
_Sal Armoniack_, the most simple and facile is this; Take one pound of
powder'd _Sal Armoniack_ and about three Pints (or pounds) of Water, put
the Salt into the Liquor, _either_ altogether, if your design be to produce
an intense, though {257} but a short coldness; _or_ at two, three, or four
several times, if you desire, that the produced coldness should rather last
somewhat longer than be so great. Stirre the powder in the Liquor with a
stick or whalebone (or some other thing that will not be injur'd by the
fretting Brine, that will be made) to hasten the dissolution of the Salt;
upon the quickness of which depends very much the intensity of the Cold,
that will ensue upon this Experiment. For the clearing up whereof, I shall
annex the following particulars.

[Sidenote: * _In the History of Cold._]

1. That a considerable degree of Cold is really produced by this operation,
is very evident: _First_ to the touch; _Secondly_, by this, that if you
make the Experiment (as for this reason I sometimes chuse to do) in a
Glass-Body or a Tankard, you may observe, that, whilst the Solution of the
Salt is making, the outside of the Metalline Vessel will, as high as the
mixture reaches within, be bedew'd (if I may so speak) with a multitude of
little Drops of Water as I have * elsewhere shown that it happens, when
mixtures of Snow and Salt, being put into Glasses or other Vessels, the
aqueous vapors that swim to and fro in the Air, and chance to glide along
the sides of the Vessels, are by the coldness thereof condens'd into Water.
And in our Armoniack Solution you may observe, that if you wipe off the Dew
from any particular part of the outside of the Vessel, whilst the solution
does yet vigorously goe on, it will quickly collect fresh Dew, which may be
sometimes copious enough to run down the sides of the Vessel. But
_Thirdly_, the best and surest way of finding out the Coldness of our
Mixture is that, which I shew'd you by plunging into it a good seal'd
Weatherglass furnish't with tincted Spirit of Wine. For the Ball of this
being put into our frigorifick mixture, the Crimson Liquor will nimbly
enough descend much lower, than when it was kept either in the open Air, in
common Water, of the same temper with that, wherein the _Sal Armoniack_ was
put to dissolve. And if you remove the Glass out of our Mixture into common
water, the tincted Spirit will, (as you may remember, it did) hastily
enough reascend for a pretty while, according to the greater or lesser
time, that it continued in the _Armoniack_ Solution. And this has succeeded
with me, when instead of removing the Mixture into _Common_ Water, I
removed it into water newly impregnated with _Salt-peter_.

{258}

2. The _Duration_ of the Cold, produc'd by this Experiment, depends upon
several Circumstances; as _First_, upon the Season of the year, and present
temperature of the Air; For, in Summer and Hot weather the Cold will sooner
decay and expire. _Secondly_, upon the Quantity of Salt and Water: For, if
both these be great, the effect will be as well more lasting, as more
considerable. _Thirdly_, for ought I yet know, we may here add the Goodness
& Fitness of the particular parcel of Salt, that is imploy'd; for, though
it be hard to discern beforehand, which will be the more, and which the
less proper; yet some trials have tempted me to suspect, that there may be
a considerable disparity, as to their fitness to produce Cold, betwixt
parcels of Salt, that are without scruple look't upon as Sal Armoniack: Of
which difference it were not perhaps very difficult to asign probable
reasons from the Nature of the Ingredients of this compound Concrete, and
the wayes of preparing it. But the Duration of the Cold may be conceived to
depend also. _Fourthly_, upon the Way of putting in the Salt into the
Water. For, if you cast it in all at once, the Water will sooner acquire an
intense degree of Coldness, but it will also the sooner return to its
former temper; Whereas, if you desire but an inferiour degree of that
Quality, but that may last longer (which wil usually be the most convenient
for the Cooling of Drinks), then you may put in the Salt by little and
little. For, keeping a long Weather-glass for a good while in our
impregnated Mixture, I often purposely try'd, that, when the tincted liquor
subsided but slowly, or was at a stand, by putting in, from time to time, 2
or 3. spoonfuls of fresh Salt, and stirring the Water to quicken the
Dissolution, the Spirit of Wine would begin again to descend, if it were at
a stand or rising, or subside much more swiftly than it did before. And if
you would lengthen the Experiment, it may not be amiss, that part of the
Sal Armoniack be but grosly beaten, that it may be the longer in
dissolving, and consequently in Cooling the Water. Whilst there are dewy
drops produced on the outside of the Vessel, 'tis a sign, that the Cold
within continues pretty strong; for when it ceases, these drops especially
in warm weather, will by degrees vanish. But a _surer_ way of measuring the
duration of the Cold, is, by removing from time to time the Seal'd
Weather-glass out of the Saline Mixture into the same common Water, with
part of which it was made. And though it be not easie to determin any thing
particularly about this matter; yet it may somewhat assist you in your
Estimates, to be inform'd, That I have in the Spring by a good
Weather-glass found a sensible adventitious Cold made by a pound of Sal
Armoniack at the utmost, to last about 2 or 3 hours.

3. To cool Drinks with this Mixture, you may put them in _thin_ Glasses,
the thinner the better; which (their orifices being stopp'd, and still kept
above the Mixture) may be moved to and fro in it, and then be immediately
pour'd out to be drunk: Though when in the Glass, I imployed, was
conveniently shap'd as, like a Sugar-loaf, or with a long Neck, I found it
not amiss to drink it out of that, without pouring it into any other; which
can scarce be done without lessning the Coolness. The refrigeration, if the
Glass viall be convenient, is quickly perform'd: And if one have a mind to
cool his hands, he may readily do it by applying them to the outside of the
Vessel, that contains the refrigerating Mixture; by whose help, pieces of
Chrystal, or Bullet for the cooling of {259} the Mouths or Hands of those
patients, to whom it may be allow'd, may be potently cool'd, and other such
refreshments may be easily procur'd.

4. How far Sal Armoniack, mingl'd with Sand or Earth, and not dissolv'd,
but only moistn'd with a little Water sprinkl'd on it, will keep Bottles of
Wine or other liquors more coole, than the Earth or that Sand alone will
do, I have not yet had opportunity by sufficient trials fully to satisfie
my self, and therefore resign that Enquiry to the Curious.

5. For the cooling of Air, and Liquors, to adjust Weather-glasses (to be
able to do which at all times of the year, was one of the chief aimes, that
made me bethink my self of this Experiment;) or to give a small quantity of
Beer &c. a moderate degree of coolness, it will not be requisite, to employ
neer so much as a whole pound of Sal Armoniack at a time. For, you may
easily observe by a seal'd Weather-glass, that a very few ounces, well
pouder'd and nimbly dissolv'd in about 4. times the weight of Water, will
serve well enough for many purposes.

6. And that you may the less, scruple at this, I shall tell you, that even
before and after Midsummer, I have found the Cold producible by our
Experiment to be considerable and useful for refrigerating of Drinks, &c.
but if the Sal Armoniack be of the fittest sort (for I intimated above,
that I suspected, 'tis not equally good) and if the season of the year do
make no disadvantagious difference, the degree of Cold, that may be
produced by no more than one pound (if not by less) of Sal Armoniack, may,
within its own Sphere of Activity, be much more vehement, than, I presume,
you yet imagine, and may afford us excellent Standards to adjust seal'd
Weather glasses by; and for several other purposes, For I remember that in
the Spring, about the end of _March_, or beginning of _April_, I was able
with one pound of Sal Armoniack, and a requisite proportion of Water, to
produce a degree of Cold much greater, than was necessary the preceding
Winter, to make it frosty Weather abroad; nay I was able to produce real
Ice in a space of time, almost incredibly short. To confirm which
particulars, because they will probably seem strange to you, I will here
annex the Transcript of an entry, that I find in a Note book of the
_Phænomena_ and success of one of those Experiments, as I then tryed it;
though I should be asham'd to expose to your perusal a thing so rudely
pen'd; if I did not hope, you would consider, that 'twas hastily written
onely for my own Remembrance. And that you may not stop at any thing in the
immediately annext Note, or the two, that follow, it will be requisite to
premise this Account of the seal'd Thermoscope; (which was a good one)
wherewith these Observations were made; That the length of the Cylindrical
pipe was 16. Inches; the Ball, about the bigness of a somewhat large
Walnut, and the Cavity of the Pipe by guess about an eight or ninth part of
an inch Diameter.

The First Experiment is thus registered. _March_ the 27th, in the Seal'd
Weather glass, when first put into the Water, the tincted Spirit rested at
8-5/8 inches; being suffered to stay there a good while, and now and then
stirr'd to and fro in the Water; it descended at length a little beneath
7-5/8 inches; then the _Sal Armoniack_ being put in, within about a quarter
of an hour or a little more it descended to 2-11/16 inches, but before that
time, in half a {260} quarter of an hour it began manifestly to freeze the
vapours and drops of water on the outside of the Glass. And when the
frigorifick power was arriv'd at the height, I several times found, that
water, thinly plac'd on the outside, whilst the mixture within was nimbly
stirr'd up and down, would freeze in a quarter of a minute (by a
Minute-watch.) At about ¾ of an hour after the infrigidating Body was put
in, the Thermoscope, that had been taken out a while before, and yet was
risen but to the lowest freezing mark, being again put in the liquor, fell
an inch beneath the mark. At about 2½ houres from the first Solution of the
Salt I found the tincted liquor to be in the midst between the freezing
marks, whereof the one was at 5½ inches (at which height when the Tincture
rested, it would usually be, some, though but a small, frost abroad;) and
the other at 4¾ inches; which was the height, to which strong and durable
Frosts had reduced the liquor in the Winter. At 3 hours after the beginning
of the Operation, I found not the Crimson liquor higher than the upper
Freezing mark newly mention'd; after which, it continued to rise very
slowly for about an hour longer; beyond which time I had not occasion to
observe it.

Thus far the _Note-book_; wherein there is mention made of a Circumstance
of some former Experiments of the like kind, which I remember was very
conspicuous in this newly recited. For, the frigorifick mixture having been
made in a Glass body (as they call it) with a large and flattish bottom, a
quantity of water, which I (purposely) spilt upon the Table, was by the
operation of the mixture within the Glass, made to freeze, and that
strongly enough, the bottom of the Cucurbite to the Table; that stagnant
liquor being turn'd into solid ice, that continued a considerable while
unthaw'd away, and was in some places about the thickness of a half Crown
piece.

Another Observation, made the same Spring, but less solemn, as meant
chiefly to shew the Duration of Cold in a high degree, is recorded in these
terms: The first time, the Seal'd Weather-glass was put in, before it
touch'd the common water, it stood at 8-1/8, having been left there a
considerable while, and once or twice agitated the water, the tincted
liquor sunk but to 7-7/8, or at furthest, 7-6/8; then the frigorifick
liquor being put into the water with circumstances disadvantagious enough
in (about) half a quarter of an hour the tincted liquor fell beneath 3¾,
and the Thermoscope, being taken out, and then put in again, an hour after
the water had been first infrigidated subsided beneath 5 inches, and
consequently within ¼ of an inch of the mark of the strongly freezing
weather.

7. Whereas the grand thing, that is like to keep this Experiment from being
as generally _Useful_, as perhaps it will prove _Luciferous_, is the
Dearness of Sal Armoniack, two things may be offered to lessen this
Inconvenience. For _first_, Sal Armoniack might be made much cheaper, if
instead of fetching it beyond-sea, our Country-men made it here at home;
(which it may easily be and I am ready to give you the Receipt, which is no
great Secret.) But _next_, I considered, that probably the infrigidating
vertue of our mixture might depend upon the peculiar Texture of the Sal
Armoniack whereby, whilest the Water is dissolving it, either some
Frigorifick particles are extricated and excited or (rather) some particles
which did before more agitate the minute parts of the water, are expell'd
(or invited out by the ambient Bodies) or {261} come to be clogg'd in their
motion: Whence it seem'd reasonable to expect that upon the Reunion of the
Saline particles into such a Body, as they had constituted before, the
redintegrated Sal Armoniack having, neer upon, the same Texture, would,
upon its being redissolv'd, produce the same, or a not much inferior degree
of Coldness: And hereupon, though I well enough foresaw that an Armoniack
solution, being boyl'd up in Earthen vessels (for Glass ones are too
chargeable) would, by piercing them, both lose some of the more subtle
parts, and thereby somewhat impaire the texture of the rest; yet I was not
deceiv'd in Expecting, that the dry Salt, remaining in the pipkins, being
redissolv'd in a due proportion of water, would very considerably
infrigidate it; as may further appear by the Notes, which for your greater
satisfaction you will find here subjoyn'd, as soon as I have told you,
that, though for want of other vessels I was first reduc'd to make use of
Earthen ones, and the rather, because some Metallin Vessels will be injur'd
by the dissolv'd Sal Armoniack, if it be boyl'd in them; yet I afterwards
found some conveniencies in Vessels of other Mettall, as of Iron; whereof
you may command a further Account.

_March_ the 29th, the Thermoscope in the Air was at 8-7/8 inches; being put
into a somewhat large evaporating glass, fill'd with water, it fell (after
it staid a pretty while, and had been agitated in the liquor) to 8. inches:
then about half the Salt, or less, that had been used _twice_ before, and
felt much less cold than the water, being put in and stirr'd about, the
tincted Spirit subsided with a visible progress, till it was faln
manifestly beneath 4. inches; and then, having caused some water to be
freshly pump'd and brought in; though the newly mention'd Solution were
mixt with it, yet it presently made the Spirit of Wine manifestly to ascend
in the Instrument, much faster, than one would have expected, &c.

And this much may suffice for this time concerning our _Frigorifick_
Experiment; which I scarce doubt but the _Cartesians_ will lay hold on as
very favourable to some of their Tenents; which you will easily believe, it
is _not_ to the Opinion, I have elsewhere oppos'd, of those Modern
Philosophers, that would have _Salt-petre_ to be the _Primum Frigidum_:
(though I found by trial, that, whilst 'tis actually dissolving, it gives a
much considerabler degree of Cold, than otherwise.) But about the
Reflexions, that may be made on this Experiment, and the Variations, and
Improvements & Uses of it, though I have divers things lying by me; yet,
since you have seen several of them already, and may command a sight of the
rest, I shall forbear the mention of them here, not thinking it proper, to
swell the bulk of this Letter with them.

       *       *       *       *       *

_An Account of two Books lately printed in London._

I. _EUCLIDIS ELEMENTA GEOMETRICA, novo ordine ac methodo demonstrata._ In
this compendious and pretty Edition, the Anonymous Author pretends to have
rendred these Elements more expeditious; by bringing all together into one
place, what belongs to one and the same subject: Comprising 1. what
_Euclid_ hath said of _Lines_, Streight, Intersecting one another, and
Parallel. 2. What he hath demonstrated of a _Single Triangle_, and of
_Triangles Compared_ one with another. 3. What of the _Circle_, and its
Properties. 4. What of _Proportions_ in Triangles and other Figures. 5.
What of _Quadrats_ and _Rectangles_, made of Lines diversly {262} cut. 6.
What of _Plane Superficies_'s. 7. What of _Solids_. After which follow the
_Problems_. The _Definitions_ are put to each _Chapter_ as need requireth.
The _Axioms_, because they are few, and almost every where necessary, are
not thus distributed in _Chapters_. The _Postulata_, are not subjoyn'd to
the _Axioms_, but reserv'd for the _Problems_, the Author esteeming, that
they being _practical_ Principles, had only place in _Problems_.

This for the _Order:_ As to the _Manner_ of Demonstrating, One and the same
is observ'd in most Propositions; all with much brevity; to the end, that
what is not of it self difficult, may not be made so, by multitude of Words
and Letters.



II. _THE ENGLISH VINE-YARD VINDICATED._ The Author (Mr. _John Rose_, his
Majesties Gardener at his Royal Garden in St. _James_'s) makes it his
business in this small Tract (a very thin Pocket-book) by a few short
Observations made by himself, to direct _Englishmen_ in the _Choice_ of the
_Fruit_, and the _Planting_ of Vine-yards; heretofore very frequently
cultivated, though of late almost quite neglected by them.

He discourses skilfully, 1. Of the _severall sorts_ of _Vines_, and what
_Grapes_ are most sutable to the _Climate_ of _England_; where he chiefly
commends the small _Black-grape_, or _Cluster-grape_; the _Parsley-grape_;
the White _Muscadine_; the _Frontiniack_; and a new _White-grape_, with a
red Wood and a dark green Leaf: All these being early ripe fruit. 2. Of the
_Soyle_, and _Scituation_ of a Vine-yard in _England_: Where, as to the
_First_, he pitches upon a _Light Soile_, having a bottom of _Chalk_ or
_Gravel_, and given to _Brambles_ observing, that no Plant whatsoever is so
connatural to the Vine for Soyl, as the _Bramble_. As for the _Scituation_
he chooses that side or declivity of a Hill, that lies to the _South_ or
_Southwest_; and is favoured with _other Hills_ somewhat higher, or _Woods_
on the _North_ and _East_, to break the rigour of those quarters. This
direction he thinks of that importance, that he affirms, that the
discouragement of the Culture of Vines in _England_ has only proceeded from
men's misinformation on this material article of _Choice_ of _Soyle_ and
_Scituation_. 3. How to _prepare_ the Ground for the Plantation, _vid._ by
plowing up the _Swarth_ in _July_, and by disposing the _Turf_ in _small_
heaps, and so burning them, and spreading the ashes over the Land; care
being taken, that by heaping too much materials together, the Earth be not
over-burnt by the excessive heat and fire, which they require to reduce
them to ashes.

What is added, of the Manner of planting the _Sets_; of Dressing, Pruning,
and Governing the Plantation; of the Ordering and Cultivating the Vine-yard
after the first four years, till it needs renewing; as also of the _manner_
and _time_, how and when to manure the Vine-yard, with Compost, will be
better understood from the Book it self, than can be here described; the
Author pretending, that, those few observations of his, as the native
production of his own Experience, being practised with care, the Vine-yards
in _England_ may be planted, govern'd and perpetuated with undoubted
success; and offering withall to furnish those, that have a desire to renew
this Culture, and to store their grounds with _Sets_ and _Plants_ of all
those sorts, which he recommends; he having a plentiful _stock_ of them
all.

       *       *       *       *       *


Printed with Licence for _John Martyn_, and _James Allestry_, Printers to
the Royal Society. 1666.

{263}

       *       *       *       *       *




_Num._ 16.

PHILOSOPHICAL
_TRANSACTIONS._

       *       *       *       *       *

_Munday_, _August_ 6. 1666.

       *       *       *       *       *

The Contents.

    _An essay of Dr. _John Wallis_, exhibiting his _Hypothesis_ about the
    _Flux and Reflux of the Sea_, taken from the consideration of the
    _Common Center of Gravity of the Earth and Moon_; together with an
    _Appendix_ of the same, containing an _Answer_ to some _Objections_,
    made by severall Persons against that _Hypothesis_. Some Animadversions
    of the same _Author_ upon Master _Hobs'_s late Book, _De Principiis &
    Ratiocinatione Geometrarum_._

       *       *       *       *       *

_An Essay of Dr. _John Wallis_, exhibiting his _Hypothesis_ about the _Flux
and Reflux of the Sea_._

How abstruse a subject in Philosophy, the _Flux and Reflux of the Sea_ hath
proved hitherto, and how much the same hath in all Ages perplexed the Minds
even of the best of _Naturalists_, when they have attempted to render an
Account of the Cause thereof, is needless here to represent. It may perhaps
be to more purpose, to take notice, that all the deficiencies, found in the
_Theories_ or _Hypotheses_, formerly invented for that End, have not been
able to deterre the Ingenious of _this_ Age from making farther search into
that Matter: Among whom that Eminent Mathematician Dr. _John Wallis_,
following his happy _Genius_ for advancing reall Philosophy, hath made it a
part of his later Inquiries and Studies, to contrive and deduce a certain
Hypothesis concerning that _Phænomenon_, taken {264} from the Consideration
of the _Common Center of Gravity of the Earth and Moon_, This being by
several Learned Men lookt upon, as a very rational Notion, it was thought
fit to offer it by the Press to the Publick, that other Intelligent Persons
also might the more conveniently and at their leisure examine the
_Conjecture_ (the Author, such is his Modesty, presenting it no otherwise)
and thereupon give in their sense, and what Difficulties may occur to them
about it, that so it may be either confirm'd or laid aside accordingly; As
the _Proposer_ himself expressly desires in the Discourse, we now, without
any more _Preamble_, are going to subjoyn, as it was by him addressed, by
way of Letter, from _Oxford_ to Mr. _Boyle, April_ 25. 1666. and afterwards
communicated to the _R. Society_, as follows:

You were earnest with me, when you last went from hence, that I would put
in writing somewhat of that, which at divers times, these three or four
years last past, I have been discoursing with your self and others
concerning the _Common Center of Gravity of the Earth and Moon_, in order
to salving the _Phænomena_ as well of the _Seas Ebbing and Flowing_; as of
some perplexities in _Astronomical Observations_ of the _Places_ of the
Celestial Bodies.

How much the World, and the great Bodies therein, are manag'd according to
the _Laws of Motion_, and _Statick Principles_, and with how much more of
clearness and satisfaction, many of the more abstruse _Phænomena_ have been
salved on such Principles, within this last Century of years, than formerly
they had been; I need not discourse to you, who are well versed in it. For,
since that _Galilæo_ and (after him) _Torricellio_, and others, have
applied _Mechanick_ Principles to the salving of _Philosophical_
Difficulties; _Natural Philosophy_ is well known to have been rendered more
intelligible, and to have made a much greater progress in less than an
hundred years, than before for many ages.

The _Seas Ebbing and Flowing_, hath so great a connexion with the _Moons_
motion, that in a manner all Philosophers (whatever other Causes they have
joyned with it), have attributed much of its cause to the _Moon_, which
either by some _occult quality_, {265} or _particular influence_, which it
hath on moyst Bodies, or by some _Magnetick vertue_, drawing the water
towards it, (which should therefore make the Water there _highest_, where
the Moon is _vertical_) or by its gravity and pressure downwards upon the
Terraqueous Globe (which would make it _lowest_ where the Moon is
_vertical_) or by whatever other means (according to the several
Conjectures of inquisitive persons,) hath so great an influence on, or at
least a connexion with, the Sea's Flux and Reflux, that it would seem very
unreasonable, to seclude the consideration of the Moons motion from that of
the Sea: The _Periods of Tides_ (to say nothing of the greatness of them
near the New moon and Full moon) so constantly waiting on the Moon's
motion, that it may be well presumed, that either the one is governed by
the other, or at least both from some common cause.

But the first that I know of, who took in the consideration of the
_Earth's_ motion, (_Diurnal_ and _Annual_) was _Galilæo_; who in his
_Systeme of the World_, hath a particular discourse on this subject: Which,
from the first time I ever read it, seemed to me so very rational, that I
could never be of other opinion, but that the true Account of this great
_Phænomenon_ was to be referred to the Earths motion, as the _Principal_
cause of it: Yet that of the Moon (for the reasons above mentioned) not to
be excluded, as to the determining the _Periods of Tides_, and other
circumstances concerning them. And though it be manifest enough, that
_Galilæo_, as to some particulars, was mistaken in the account which there
he gives of it; yet that may be very well allowed, without any blemish to
so deserving a person, or prejudice to the _main Hypothesis_: For that
Discourse is to be looked upon onely as an _Essay_ of the _general
Hypothesis_; which as to _particulars_ was to afterwards adjusted, from a
good _General History of Tides_; which it's manifest enough that he had
not; and which is in a great measure yet wanting. For were the matter of
Fact well agreed on, it is not likely, that several Hypotheses should so
far differ, as that one should make the Water _then_ and _there_ at the
Highest, _where_ and _when_ the other makes it at the Lowest; as when the
Moon is Vertical to the place. {266}

And what I say of _Galilæo_, I must in like manner desire to be understood
of what I am now ready to say to you. For I do not profess to be so well
skilled in the History of Tides, as that I will undertake presently to
accommodate my _general Hypothesis_ to the _particular cases_; or that I
will indeed undertake for the certainty of it, but onely as an _Essay_
propose it to further consideration; to stand or fall, as it shall be found
to answer matter of Fact. And truly had not your importunity (which is to
me a great Command) required me to do it, I should not so easily have drawn
up any thing about it, till I had first satisfied my selfe, how well the
Hypothesis would answer Observation: Having for divers years neglected to
do it, waiting a time when I might be at leisure throughly to prosecute
this design.

But there be two reasons, by which you have prevailed with me, at least to
do something. _First_, because it is the common Fate of the _English_, that
out of a modesty, they forbear to publish their Discoveries, till
prosecuted to some good degree of certainty and perfection; yet are not so
wary, but that they discourse of them freely enough to one another, and
even to Strangers upon occasion; whereby others, who are more hasty and
venturous, comming to hear of the notion, presently publish something of
it, and would be reputed thereupon, to be the first Inventers thereof:
though even that little, which they can then say of it, be perhaps much
less, and more imperfect, than what the true Authors could have published
long before, and what they had really made known (publikely enough, though
not in print) to many others. As is well known amongst us as to the
business of the _Lymphatick Vessels_ in _Anatomy_; the _Injection of
Liquors into the veins of Living animals_; the _Exhibiting of a straight
line equal to a crooked_; the _spot in Jupiter_, whence his motion about
his own Axis may be demonstrated; and many other the like considerable
Inventions.

The _other_ Reason (which, with me, is more really of weight, though even
the former be not cotemptible) is, because, as I have been already for at
least three or four years last past diverted from prosecuting the inquiry
or perfecting the Hypothesis, as I had thoughts to do; so I do not know,
but like Emergencies may divert me longer; and whether I shall ever so
{267} do it, as to bring it to perfection, I cannot determine. And
therefore, if as to my self any thing should _humanitus accidere_; yet
possibly the notion may prove worth the preserving to be prosecuted by
others, if I do it not. And therefore I shall, at least to your self, give
some general account of my present imperfect and undigested thoughts.

I consider therefore, that in the Tides, or the Flux and Reflux of the Sea,
besides extraordinary Extravagancies or Irregularities, whence great
Inundations or strangly high Tides do follow, (which yet perhaps may prove
not to be so meerly accidental as they have been thought to be, but might
from the regular Laws of Motion, if well considered, be both well accounted
for and even foretold;) There are these _three_ notorious Observations made
of the Reciprocation of Tides. _First_, the _Diurnal_ Reciprocation;
whereby twice in somewhat more than 24. hours, we have a Floud and an Ebbe;
or a High-water and Low-water. _Secondly_, the _Menstrual_; whereby in one
_Synodical_ period of the Moon, suppose from Full-moon to Full-moon, the
Time of those Diurnal Vicissitudes doth move round through the whole
compass of the [Greek: Nuchthêmeron], or Natural day of twenty four hours:
As for instance, if at the Full-moon the full Sea be at such or such a
place just at Noon, it shall be the next day (at the same place) somewhat
before One of the clock; the day following, between One and Two; and so
onward, till at the New moon it shall be at midnight; (the other Tide,
which in the Full moon was at midnight, now at the New-moon coming to be at
noon;) And so forward till at the next Full-moon, the Full sea shall (at
the same place) come to be at Noon again: Again, That of the Spring-tides
and Neap-tides (as they are called;) about the Full-moon and New-moon the
Tides are at the Highest, at the Quadratures the Tides are at the Lowest:
And at the times intermediate, proportionably. _Thirdly_, the _Annual_;
whereby it is observed, that at sometimes of the year, the Spring-tides are
yet much higher than the Spring-tides at other times of the year: Which
Times are usually taken to be at the Spring and Autumne; or the two
Æquinoxes; but I have reason to believe (as well from my own Observations,
for many years, as of others who have been {268} much concerned to heed it,
whereof more will be said by and by;) that we should rather assign the
beginnings of _February_ and _November_, than the two _Æquinoxes_.

Now in order to the giving account of these three Periods, according to the
_Laws of Motion_ and _Mechanick Principles_; We shall _first_ take for
granted, what is now adayes pretty commonly entertained by those, who treat
of such matters; _That a Body in motion is apt to continue its motion, and
that in the same degree of celerity, unless hindred by some contrary
Impediment_; (like as a Body at rest, to continue so, unless by some
sufficient mover, put into motion:) And accordingly (which daily experience
testifies) if on a Board or Table, some loose incumbent weight, be for some
time moved, & have thereby contracted an _Impetus_ to motion at such a
rate; if that Board or Table chance by some external obstacle, or
otherwise, to be stopped or considerably retarded in its motion, the
incumbent loose Body will shoot forward upon it: And contrarywise, in case
that Board or Table chance to be accelerated or put forward with a
considerably greater speed than before, the loose incumbent Body, (not
having yet obtained an equal _Impetus_ with it) will be left behind, or
seem to fly backward upon it. Or, (which is _Galilæo_'s instance,) if a
broad Vessel of Water, for some time evenly carried forward with the water
in it, chance to meet with a stop, or to slack its motion, the Water will
dash forward and rise higher at the fore part of the Vessel: And,
contrarywise, if the Vessel be suddenly put forward faster than before; the
Water will dash backwards, and rise at the hinder part of the Vessel. So
that an Acceleration or Retardation of the Vessel, which carries it, will
cause a rising of the Water in one part, and a falling in another: (which
yet, by its own weight, will again be reduced to a Level as it was before.)
And consequently, supposing the Sea to be but as a loose Body, carried
about with the Earth, but not so united with it, as necessarily to receive
the same degree of _Impetus_ with it, as its fixed parts do: The
acceleration or retardation in the motion of this or that part of the
Earth, will cause (more or less, according to the proportion of it) such a
dashing of the Water, or rising at one part, with a Falling at another, as
is that, which we call the Flux and Reflux of the Sea. {269}

[Illustration]

Now this premised, We are next, with him, to suppose the Earth carried
about with a double motion; The one _Annual_, as (_Fig._ 1.) in B E C the
great Orb, in which the Center of the Earth B, is supposed to move about
the Sun A.

The other _Diurnal_, whereby the whole moves upon its own _Axis_, and each
point in its surface describes a Circle, as D E F G.

It is then manifest, that if we suppose, that the Earth moved but by any
one of these motions, and that regularly, (with an equal swiftness;) the
Water, having once attained an equal _Impetus_ thereunto, would still hold
equal pace with it; there being no occasion, from the Quickening or
Slackening of the Earths motion, (in that part where the Water lyeth) for
the Water thereon either to be cast Forward or fall Backward; and thereby
to accumulate on the other parts of the Water: But the true motion of each
part of the Earths surface being compounded of those two motions, the
_Annual_ and _Diurnal_; (the _Annual_ in B E C being, as _Galilæo_ there
supposeth, about three times as fast as a _diurnal_ motion in a great
Circle, as D E F;) while a Point in the Earths surface moves about its
Center B. from G. to D. and E. and at the same time, its Center B. be
carried forwards to C; the true motion of that Point forwards, is made up
of both those motions; to wit, of B to C, and of G to E; but while G moves
by D to E, E moves backward by F to G, contrary to the motion of B to C; so
that the true motion of E, is but the difference of B C, and E G: (for,
beside the motion of B above the Center; G. is also put forward as much as
from G to E; and E put backward as much as from E to G:) so that the
_Diurnal_ motion, in that part of the Earth, which is next the Sun, as E F
G, doth abate the progress of the _Annual_, (and most of all at F;) and in
the other part, which is from the Sun, as G D E, it doth increase it, (and
most of all at D.) that is, in the day time there is abated, in the night
time is added to the _Annual_ motion, about as much as is G E, the Earths
_Diameter_. Which would afford us a Cause of two Tides in twenty four
hours; the One upon the greatest Acceleration of motion, the Other upon its
greatest Retardation.

And thus far _Galilæo_'s Discourse holds well enough; But then {270} in
this it comes short; that as it gives an Account of two Tides; so those two
Tides are alwayes to be at F and D; that is, at _Noon_ and _Midnight_;
whereas Experience tells us, that the Time of Tides, moves in a _moneths
space_ through all the 24. hours. Of which he gives us no account. For
though he do take notice of a Menstrual Period; yet he doth it onely as to
the _Quantity_ of the Tides; greater or less; not as to the _Time_ of the
_Tides_, sooner or later.

[Sidenote: * _Vid. Riccioli Almagest. novum_, Tom. 1, lib. 4. cap. 10. n.
111. pag. 216. 2.]

To help this, there is one (_Vid.* Jo. Baptista Balianus_) who makes the
_Earth_ to be but a _secondary_ Planet; and to move, not directly about the
Sun, but about the Moon, the Moon meanwhile moving about the Sun; in like
manner as we suppose the Earth to move about the Sun, and the Moon about
it.

But this, though it might furnish us with the foundation of a _Menstrual_
Period of Accelerations and Retardations in the compound motion of several
parts of the Earths surface; yet I am not at all inclined to admit this as
a _true Hypothesis_, for divers Reasons, which if not demonstrative, are
yet so consonant to the general Systeme of the World, as that we have no
good ground to disbelieve them. For 1. The Earth being undeniably the
greater Body of the two (whereof there is no doubt to be made) it cannot be
thought probable, that this should be carried about by the Moon, lesser
than it self: The contrary being seen, not onely in the _Sun_, which is
bigger than any of the Planets, which it carryes about; but in _Jupiter_,
bigger than any of his _Satellites_; and _Saturne_, bigger than his. 2. As
the _Sun_ by it's motion about it's own Axis, is with good reason judged to
be the _Physical_ cause of the _Primary_ Planets moving about it; So there
is the like reason to believe, that _Jupiter_ and _Saturne_ moving about
their Axes, are the Physical cause of their _Satellites_ moving about them,
which motion of _Jupiter_ hath been of late discover'd, by the help of a
_fixed_ Spot discern'd in him; and we have reason to believe the like of
_Saturne:_ Whether _Venus_ and _Mercury_ (about whom no _Satellites_ have
been yet observed) be likewise so moved; we have not yet the like ground to
determine: But we have of _Mars_; from {271} the Observations of Mr. _Hook_
made in _February_ and _March_ last, and by him communicated to the _Royal
Society_, and since Printed in the _Transactions_, published _Apr._ 2.
1666. consonant to the like observations of _Jupiter_, made by him in
_May._ 1664, and since communicated to the same _Society_; and then
published in the _Transactions_, of _March._ 6. then next following. Now
that the Earth hath such a motion about its own _Axis_ (whereby it might be
fitted to carry about the Moon) is evident by its _Diurnal_ motion. And it
seems as evident that the Moon hath not; because of the same side of the
Moon alwaies turned towards us; which could not be, if the Moon carried the
Earth about: Unlesse we should say, that it carries about the Earth in just
the same Period, in which it turnes upon its own Axis: Which is contrary to
that of the Sun carrying about the Planets: the shortest of whose Periods,
is yet longer than that of the Suns moving about its own Axis. And the like
of _Jupiter_, shorter than the Period of any of his _Satellites_; if at
least the Period of his conversion about his Axis, lately said to be
observed, prove true. (Of _Saturn_ we have not yet any Period assigned; but
it's likely to be shorter, than that of his _Satelles_.) And therefore we
have reason to believe, not that by the Moons motion about its Axis the
Earth should be carried by a contemporary Period (whereby the same face of
the Moon should be ever towards us;) but that by the Earths revolution
about its Axis in 24. hours, the Moon should be carried about it in about
29. dayes, without any motion on its own Axis: And accordingly, that the
_Secondary_ Planets about _Jupiter_ and _Saturn_, are not (like their
_Principals_) turned about their own Axis. And therefore I am not at all
inclined to believe, that the _Menstrual_ Period of the Tides with us, is
to be salved by such an Hypothesis.

In stead of this, that _Surmise_ of mine, (for I dare not yet, with
confidence give it any better name,) of what I have spoken to you
heretofore, (and which hath occasioned this present account which I am now
giving you,) is to this purpose.

The Earth and Moon being known to be Bodies of so great connexion (whether
by any Magnetick, or what other Tye, I will not determine; nor need I, as
to this purpose;) as that {272} the motion of the one follows that of the
other; (The Moon observing the Earth as the Center of its _periodick_
motion:) may well enough be looked upon as _one Body_, or rather _one
Aggregate of Bodies_, which have _one common center of Gravity_; which
Center (according to the known Laws of _Staticks_) is in a streight Line
connecting their respective Centers, so divided as that its parts be in
reciprocal proportion to the Gravities of the two Bodies. As for Example;
Suppose the Magnitude (and therefore probably, the Gravity) of the Moon to
be about an _One and fourtieth part_ of that of the Earth; (and thereabouts
_Hevelius_ in his _Selenography_ page 203. doth out of _Tycho_, estimate
the proportion; and an exact certainty is not necessary to our present
businesse.) And the distance of the Moons Center from the Center of the
Earth, to be about _fifty six Semidiameters_ of the Earth, (as thereabouts
he doth there estimate it, in its middle distance; and we need not be now
very accurate in determining the numbers; wherein Astronomers are not yet
very well agreed.) The distance of the Common Center of Gravity of the two
Bodies, will be from that of the Earth, about a two and fourtieth part of
fifty six Semidiameters; that is, about 56/42 or 4/3 of a Semidiameter;
that is about 1/3 of a Semidiameter of the Earth, above its surface, in the
Air, directly between the Earth and Moon.

Now supposing the Earth and Moon, joyntly as one Body, carried about by the
Sun in the great Orb of the _Annual_ motion; this motion is to be
estimated, (according to the Laws of _Staticks_, in other cases,) by the
motion of the common Center of Gravity of both Bodies. For we use in
_Staticks_, to estimate a Body, or Aggregate of Bodies, to be moved
upwards, downwards, or otherwise, so much as its Common Center of Gravity
is so moved, howsoever the parts may change places amongst themselves.

And accordingly, the Line of the _Annual_ motion, (whether _Circular_ or
_Elliptical_; of which I am not here to dispute,) will be described, not by
the Center of the Earth (as we commonly estimate it, making the Earth a
Primary and the Moon a Secondary Planet,) nor by the Center of the Moon,
(as they would do, who make the Moon the Primary and the Earth a {273}
Secondary Planet, against which we were before disputing:) But by the
_Common Center of Gravity of the Bodies, Earth and Moon_, as one Aggregate.

[Sidenote: See Fig. 2. and 3.]

Now supposing A B C D E to be a part of the great Orb of the _Annual_
motion, described by the Common Center of Gravity, in so long time as from
a _Full-Moon_ at A to the next _New-Moon_ at E; (which, though an Arch of a
_Circle_ or _Ellipse_, whose Center we suppose at a due distance below it;
yet being put about 1/25 of the whole, may well enough be here represented
by a streight Line:) the Center of the Earth at T, and that of the Moon at
L, must each of them (supposing their common Center of Gravity to keep the
Line A E) be supposed to describe a _Periphery_ about that Common Center,
as the Moon describes her Line of _Menstrual_ motion (Of which I have (in
the _Scheme_) onely drawn that of the _Earth_; as being sufficient to our
present purpose; parallel to which, if need be, we may suppose one
described by the Moon; whose distance is also to be supposed much greater
from T than in the _figure_ is expressed, or was necessary to expresse.)
And in like manner E F G H I, from that _New moon_ at E, to the next
_Full-moon_ at I.

[Illustration]

From A to E (from Full moon to New moon,) T moves (in its own _Epicycle_)
upwards from the Sun: And from E to I, (from New moon to Full moon) it
moves downwards, toward the Sun. Again, from C to G, (from last quarter to
the following first quarter,) it moves _forwards according_ to the _Annual_
motion; But from G forward to C, (from the first Quarter to the ensuing
last Quarter,) it moves _contrary_ to the _Annual_ motion.

It is manifest therefore, according to this Hypothesis, that from Last
quarter to First quarter (from C to G, while T is above the Line of the
_Annual_ motion) its _Menstrual_ motion in its Epicycle _adds_ somewhat of
Acceleration to the _Annual_ motion, and most of all at E, the New-moon:
And from the first to the last quarter (from G forward to C, while T is
below the Line of the _Annual_ motion,) it _abates_ of the _Annual_ motion;
and most of all at I, or A the Full-moon.

So that in pursuance of _Galilæo's_ Notion, the _Menstrual_ {274} adding to
or detracting from the _Annual_ motion, should either leave behinde, or
cast forward, the loose waters incumbent on the Earth, (and thereby cause a
Tide, or accumulation of Waters) and most of all at the Full Moon and
New-moon, where those Accelerations or Retardations are greatest.

Now this _Menstrual_ motion, if nothing else were superadded to the
_Annual_, would give us two Tides in a moneth, and no more; (the one upon
the Acceleration, the other on the Retardation;) at New moon and Full-moon;
and two Ebbs, at the two Quarters; and in the Intervals, Rising and Falling
water.

But the _Diurnal_ motion superadded, doth the same to this _Menstrual_,
which _Galilæo_ supposeth it to do to the _Annual_; that is, doth _Add_ to,
or _Subtract_ from, the _Menstrual_ Acceleration or Retardation; and so
gives us Tide upon Tide.

[Illustration]

For in whatsoever part of its Epicycle, we suppose T to be; yet because,
while by its _Menstrual_ motion the Center moves in the Circle L T N; each
point in its surface, by its diurnal motion moves in the Circle L M N:
whatever effect (accelerative or tardative) the _Menstrual_ would give,
that effect by the _Diurnal_ is increased in the parts L M N (or rather l M
n. the Semicircle) and most of all at M: but diminished in the parts N O L
(or rather n O l) and most of all at O. So that at M, and O, (that is when
the Moon is in the _Meridian_ below or above the _Horizon_,) we are to have
the Diurnal Tide or High-water, occasioned by the greatest Acceleration or
Retardation, which the _Diurnal_ Arch gives to that of the _Menstrual_:
which seems to be the true cause of the _Daily Tides_. And withall gives an
account, not onely why it should be _every_ day; but like wise, why at
_such a time_ of the day; and why this time should in a moneth run through
the whole 24 hours; _viz._ because the Moons coming to the _Meridian_ above
and below the _Horizon_, (or as the Seamen call it, the _Moons Southing_,
and _Northing_,) doth so: As likewise of the _Spring tides_ and
_Neap-tides_. For, when it so happens, that the _Menstrual_ and _Diurnal_
Accelerations or Retardations, be coincident, (as at New moons and
Full-moons they are,) the effect must needs be the greater. And although
(which is not to be dissembled) this happen {275} but to one of the two
Tides; that is, the Night-tide at the New-moon (when both motions do most
of all Accelerate,) and the Day-tide at Full-moon (when both do most Retard
the _Annual_ motion;) Yet, this tide being thus raised by two concurrent
causes; though the next Tide have not the same cause also, the _Impetus_
contracted will have influence upon the next Tide; Upon a like reason, as a
_Pendulum_ let fall from a higher Arch, will (though there be no new cause
to occasion it) make the Vibration on the other side (beyond the
Perpendicular) to be also greater: Or, of water in a broad Vessel, if it be
so jogged, as to be cast forward to a good height above its Levell, will
upon its recoyling, by its own gravity, (without any additional cause)
mount so much the higher on the hinder part.

But here also we are to take notice, that though all parts of the Earth by
its _Diurnal_ motion do turn about its Axis, and describe _parallel_
Circles; yet not _equal_ Circles; but _greater_ neer the _Æquinoctial_, and
_lesser_ near the _Poles_, which may be a cause why the Tides in some parts
may be much greater than in others. But this belongs to the _particular_
considerations, (of which we are not now giving an Account:) not to the
_general_ Hypothesis.

Having thus endeavoured to give an account of the _Diurnal_ and _Menstrual_
Periods of Tides; It remains that I endeavour the like as to the _Annual_.
Of which there is, at least, thus much agreed; That, at some times of the
year, the Tides are noted to be much higher, than at other times.

But here I have a double task; _First_, to rectify the Observation; and
_then_, to give an account of it.

As to the _First_; It having been observed (grosly) that those high Tides
have used to happen about the _Spring_ and _Autumn_; it hath been generally
taken for granted (without any more nice observation) that the _two
Æquinoxes_ are the proper times, to which these _Annual high Tides_ are to
be referred; And such causes sought for, as might best sute with such a
Supposition.

But it is now, the best part of twenty years, since I have had frequent
occasions to converse with some Inhabitants of _Rumney-marsh_ in _Kent_;
where the Sea being kept out with great Earthen walls, that it do not at
high water overflow the Levell; {276} and the Inhabitants livelyhood
depending most on grazing, or feeding Sheep; they are (as you may believe
they have reason to be) very vigilant and observant, at what times they are
most in danger of having their Lands drowned. And I find them generally
agreed, by their constant Observations, (and Experience dearly bought) that
their times of danger are about the beginning of _February_ and of
_November_; that is, at those Spring Tides which happen near those times;
to which they give the names of _Candlemass-stream_ and
_Allhallond-stream_; And if they scape those Spring-tides, they apprehend
themselves out of Danger for the rest of the year. And as for _March_ and
_September_ (the two _Æquinoxes_) they are as little solicitous of them, as
of any other part of the year.

This, I confess, I much wondred at, when I first heard it; and suspected it
to be but a mistake of him, that first told me, though he were indeed a
person not likely so to be mistaken, in a thing wherein he was so much
concerned: But I soon found, that it was not onely his, but a general
observation of others too; both there, and elsewhere along the Sea coast.
And though they did not pretend to know any reason of it, (nor so much as
to enquire after it;) Yet none made doubt of it; but would rather laugh at
any that should talk of _March_ and _September_, as being the dangerous
times. And since that time, I have my self very frequently observed (both
at _London_ and elsewhere, as I have had occasion), that in those months of
_February_ and _November,_ (especially _November_), the Tides have run much
higher, than at other times: Though I confess, I have not been so diligent
to set down those Observations, as I should have done. Yet this I do
particularly very well remember, that in _November_ 1660. (the same year
that his Majesty returned) having occasion to go by Coach from the _Strand_
to _Westminster_, I found the Water so high in the middle of _King-street_,
that it came up, not onely to the Boots, but into the Body of the Coach;
and the _Pallace-yard_ (all save a little place near the _West-End_)
overflow'd; as likewise the Market-place; and many other places; and their
Cellars generally filled up with Water. And in _November_ last, 1665. it
may yet be very well remembred, what very high Tides there were, not onely
on the Coasts of _England_, (where much hurt was {277} done by it) but much
more, in _Holland_, where by reason of those Inundations, many Villages and
Towns were overflow'd. And though I cannot so particularly name other
years, yet I can very safely say, that I very often observed Tides
strangely high about those times of the year.

This Observation did for divers years cause me much to wonder, not only
because it is so contrary to the received opinion of the two _Æquinoxes_;
but because I could not think of any thing signal at those times of the
year: as being neither the two _Æquinoxes_, nor the two _Solstices_, nor
the Sun's _Apogæum_ and _Perigæum_: (or Earths _Aphelium_ and
_Perihelium_;) nor indeed, at contrary times of the year, which at least,
would seem to be expected. From _Alhollandtide_ to _Candlemass_ being but
three months; and from thence to _Alhollandtide_ again nine months.

At length it came into my mind, about four years since, that though there
do not about these times happen any _single_ signal Accident, which might
cast it on these times, yet there is a _compound of two_ that may do it;
Which is the _Inequality_ of the _Natural day_ (I mean that of 24. hours,
from noon to noon) arising at least from a double cause; either of which
singly would cast it upon other times, but both joyntly on those.

It's commonly thought, how unequal soever the length be of the _Artificial_
dayes as contradistinguished to nights, yet that the _Natural_ Days,
reckoning from noon to noon, are all _equal_: But _Astronomers_ know well,
that even these dayes are _unequal_.

For, this _Natural_ Day is measured _not onely_ by one intire conversion of
the _Æquinoctial_, or 24. _Æquinoctial_ hours, (which is indeed taken to be
performed in equal times,) _but_ increases by so much, as answers to that
part of the _Sun's_ (or _Earths_,) Annual motion as is performed in that
time. For, when that part of the _Æquinoctial_, which (with the _Sun_) was
the _Meridian_ yesterday at noon, is come thither again to day, it is not
yet _Noon_ (because the Sun is not now at the place where yesterday he was,
but is gone forward about one degree, more or less) but we must stay till
that place, where the _Sun_ now is, comes to the _Meridian_ before it be
now _Noon_.

Now this Additament (above the 24 _Æquinoctial_ hours, or intire conversion
of the _Æquinoctial_) is upon a double account {278} unequal. _First_,
because the Sun, by reason of its _Apogæum_ and _Perigæum_, doth not at all
times of the year dispatch in one day an equal Arch of the _Ecliptick_; but
greater Arches neer the _Perigæum_, which is about the middle of
_December_; and lesser neer the _Apogæum_, which is about the middle of
_June_: As will appear sufficiently by the _Tables_ of the Sun's Annual
motion. _Secondly_, though the Sun should in the _Ecliptick_ move alwaies
at the same rate; yet equal Arches of the _Ecliptick_ do not in all parts
of the _Zodiack_ answer to equal Arches of the _Æquinoctial_, by which we
are to estimate time: Because some parts of it, as about the two
_Solsticial_ Points, lie nearer to a _parallel_ position to the
_Æquinoctial_, than others, as those about the two _Æquinoctial_ points,
where the _Ecliptick_ and _Æquinoctial_ do intersect; whereupon an Arch of
the _Ecliptick_, neer the _Solsticial_ points answers to a greater Arch of
the _Æquinoctial_, than an Arch equal thereunto neer the _Æquinoctial_
points: As doth sufficiently appear by the _Tables_ of the Suns _right
Ascension_.

According to the _first_ of these causes, we should have the longest
_natural_ daies in _December_, and the shortest in _June_, which if it did
operate alone, would give us at those times two _Annual_ High-waters.

According to the _second_ cause, if operating singly, we should have the
longest daies at the two Solstices in _June_ and _December_, and the two
shortest at the _Æquinoxes_ in _March_ and _September_; which would at
those times give occasion of four _Annual_ High-waters.

But the true _Inequality_ of the Natural Days, arising from a _Complication
of those two causes_, sometimes crossing and sometimes promoting each each
other: though we should find some increases or decreases of the _Natural_
daies at all those seasons answerable to the respective causes (and perhaps
of Tides proportionably thereunto:) yet the longest and shortest _natural
daies_ absolutely of the whole year (arising from this complication of
Causes) are about those times of _Allhallontide_ and _Candlemas_; (or not
far from them) about which those _Annual_ High-tides are found to be: As
will appear by the _Tables of Æquation_ of _Natural_ daies. And therefore I
think, we may with very good reason cast this _Annual_ Period upon that
cause, or rather {279} complication of causes. For (as we before shewed in
the _Menstrual_ and _Diurnal_) there will, by this inequality of Natural
daies, arise a _Physical_ Acceleration and Retardation of the Earths _Mean_
motion, and accordingly a casting of the Waters backward or forward; either
of which, will cause an Accumulation or High-water.

'Tis true, that these longest and shortest daies, do (according to the
_Tables_, some at least) fall rather before, than after _Alhallontide_ and
_Candlemas_ (to wit the ends of _October_ and _January_;) but so do also
(sometimes) those high Tydes: And it is not yet so well agreed amongst
_Astronomers_, what are all the Causes (and in what degrees) of the
Inequality of Natural daies; but that there be diversities among them,
about the true time: And whether the introducing of this New Motion of the
Earth in its _Epicycle_ about this Common Center of _Gravity_, ought not
therein also to be accounted for, I will not now determine: Having already
said enough, if not too much, for the explaining of this general
Hypothesis, leaving the particularities of it to be adjusted according to
the true measures of the motions; if the General Hypothesis be found fit to
be admitted.

Yet this I must add, (that I be not mistaken) that whereas I cast the time
of the daily Tydes to be at all places, when the Moon is there in the
_Meridian_; it must be understood of _open_ Seas, where the water hath such
free scope for its motions, as if the whole Globe of Earth were equally
covered with water: Well knowing, that in _Bayes_ and _In land-Channels_,
the position of the Banks and other like causes must needs make the times
to be much different from what we suppose in the open Seas: And likewise,
that even in the Open Seas, _Islands_, and _Currents_, _Gulfs_ and
_Shallows_, may have some influence, though not comparable to that of
_Bays_ and _Channels_. And moreover, though I think, that Seamen do
commonly reckon the time of High-water in the _Open Seas_, to be then, when
the Moon is there in the _Meridian_ (as this Hypothesis would cast it:) Yet
I do not take my self to be so well furnished with a _History of Tides_, as
to assure my self of it; much less to accommodate it to particular places
and cases.

Having thus dispatched the main of what I had to say {280} concerning the
Seas Ebbing and Flowing: Had I not been already too tedious, I should now
proceed to give a further reason, why I do introduce this consideration of
the _Common Center of Gravity_ in reference to _Astronomical Accounts_. For
indeed, that which may possibly seem at first to be an Objection _against_
it, is with me one reason _for_ it.

It may be thought perhaps, that if the Earth should thus describe an
_Epicycle_ about the Common Center of Gravity, it would (by this its change
of place) disturbe the _Cælestial_ motions; and make the _apparent_ places
of the Planets, especially some of them, different from what they would
otherwise be. For though so small a removal of the Earth, as the _Epicycle_
would cause (especially if its _Semidiameter_ should not be above 1-1/3 of
the Earths Semidiameter) would scarce be sensible (if at all) to the
remoter Planets; yet as to the nearer it might.

Now though what _Galilæo_ answers to a like Objection in his _Hypothesis_;
(that its possible there may be some small difference, which _Astronomers_
have not yet been so accurate, as to observe) might here perhaps serve the
turn; Yet my answer is much otherwise; to wit, that such difference hath
been observed and hath very much puzzeled _Astronomers_ to give an account
of. About which you will find Mr. _Horrocks_ (in some of his Letters,
whereof I did formerly, upon the Command of the _Royal Society_, make an
_Extract_) was very much perplexed; and was fain, for want of other relief,
to have recourse to somewhat like _Keplers_ amicable _Fibres_, which did
according to the several positions of the Moon, accelerate or retard the
Moon's motion; which _amicable Fibres_ he had no affection to at all (as
there appears) if he could any other waies give account of those little
inequalities; and would much rather (I doubt not) have embraced this Notion
of the Common Center of Gravity, to salve the _Phænomenon_, had it come to
his mind, or been suggested to him. And you find, that other _Astronomers_
have been seen to bring in (some upon one supposition, some upon another)
some kind of _Menstrual Æquation_, to solve the inequalities of the Moon's
motion, according to her _Synodical_ Revolution, or different Aspects (of
New-moon, Full Moon, &c.) beside what concerns her own _Periodical_ motion.
{281}

For which, this consideration of the _Common Center of Gravity of the Earth
and Moon_, is so proper a remedy (especially if it shall be found precisely
to answer those _Phænomena_, which I have not Examined, but am very apt to
believe) that it is so far from being, with me, an Objection against it,
that it is one of the reasons, which make me inclinable to introduce it.

I must before I leave this, add one Consideration more, That if we shall
upon these Considerations think it reasonable, thus to consider the _Common
Center of Gravity of the Earth and Moon_; it may as well be thought
reasonable, that the like Consideration should be had of _Jupiter_ and his
four _Satellites_, which according to the Complication of their several
motions, will somewhat change the position of _Jupiter_, as to that _Common
center of Gravity_ of all these Bodies; which yet, because of their
smallness, may chance to be so little, as that, at this distance, the
change of his apparent place may not be discernable. And what is said of
_Jupiter_, is in the like manner to be understood of _Saturne_ and his
_Satelles_, discovered by _Hugenius_: For all these _Satellites_ are to
their _Principals_, as so many Moons to the Earth. And I do very well
remember, in the Letters forecited, Mr. _Horrocks_ expresseth some such
little inequalities in _Saturnes_ motion, of which he could not imagine
what account to give, as if (to use his Expression) this crabbed _Old
Saturn_ had despised his _Youth_. Which, for ought I know, might well
enough have been accounted for, if at that time the _Satelles_ of _Saturn_
had been discovered, and that Mr. _Horrocks_ had thought of such a notion
as the _Common Center of Gravity_ of _Saturn_ and his _Companion_, to be
considerable, as to the guiding of his motion.

You have now, in obedience to your Commands, an Account of my thoughts, as
to this matter, though yet immature and unpolished: What use you will
please to make of them, I shall leave to your prudence, &c.

       *       *       *       *       *

_An _APPENDIX_, written by way of Letter to the _Publisher_; Being an
answer to some Objections, made by several Persons, to the precedent
Discourse._

I Received yours; and am very well contented, that _objections_ be made
against my _Hypothesis_ concerning _Tydes_: being {282} proposed but as a
conjecture to be examined; and, upon that Examination, rectified, if there
be occasion; or rejected, if it will not hold water.

1. To the first objection of those you mention; _That it appears not how
two Bodies, that have no tye, can have one common Center of Gravity:_ that
is (for so I understand the intendment of the objection) can act or be
acted in the same manner, as if they were connected: I shall onely answer,
that it is harder to shew _How_ they have, than _That_ they have it. That
the Load-stone and Iron have somewhat equivalent to a Tye; though we see it
not, yet by the effects we know. And it would be easy to shew, that two
Load-stones, at once applyed, in different positions, to the same Needle,
at some convenient distance, will draw it, not to point directly to either
of them, but to some point between both; which point is, as to those two,
the _common Center of Attraction;_ and it is the same, as if some _one_
Load-stone were in that point. Yet have these two Load stones no connection
or tye, though a _Common Center of Virtue_ according to which they joyntly
act. And as to the present case, _How_ the Earth and Moon are connected; I
will not now undertake to shew (nor is it necessary to my purpose;) but,
That there is somewhat, that doth connect them, (as much as what connects
the Load-stone, and the Iron, which it draws,) is past doubt to those, who
allow them to be carryed about by the Sun, as one Aggregate or Body, whose
parts keep a respective position to one another: Like as _Jupiter_ with his
_four Satellites_, and _Saturn_ with his _one_. Some Tye there is, that
makes those _Satellites_ attend their _Lords_, and move in a Body; though
we do not _See_ that Tye; nor _Hear_ the Words of Command. And so here.

2. To the second objection; _That, at Chatham and in the Thames, the Annual
Spring-tydes, happen about the Æquinoxes; not (as this Hypothesis doth
suppose elsewhere to have been observed) about the beginning of February
and November._ If their meaning be, that Annual High Tydes, do then happen,
and then onely: If this prove true, it will ease me of half my work. For it
is then easily answered, that it depends upon the _Obliquity of the
Zodiack_; the parts of the Æquinoctial answering to equal parts of the
{283} _Zodiack_, being neer the Solstitial points greatest, and near the
Æquinoctial points least of all. But beside this _Annual Vicissitude of the
Æquinoxes_, not to say, of the 4. Cardinal Points (which my Hypothesis doth
allow and assert;) I believe it will be found, that there is _another
Annual vicissitude_ answering to the Suns _Apogæum_ and _Perigæum_. And
that the greatest Tydes of all, will be found to be upon a result of these
two causes Cooperating: which (as doth the Inequality of Natural dayes,
depending on these same causes) will light nearer the times, I mention. To
what is said to be observed at _Chatham_ and in the _Thames_, contrary to
that I allege as observed in _Rumney marsh_: I must at present [Greek:
apechein], and refer to a _melius inquirendum_. If those who object this
contrary observation, shall, after this notice, find, upon new Observations
heedfully taken, that the _Spring-tydes_ in _February_ and _November_, are
not so high, as those in _March_ and _September_; I shall then think the
objection very considerable. But I do very well remember, that I have seen
in _November_, very high Tydes at _London_, as well as in _Rumney Marsh_.
And, the time is not yet so far past, but that it may be remembered (by
your self or others then in _London_) whether in _November_ last when the
Tydes were so high at _Dover_, at _Deal_, at _Margate_, and all along the
Coast from thence to _Rumney Marsh_, as to do in some of those places much
hurt, (and, in _Holland_, much more;) whether, I say, there were not also
at the same time, at _London_, (upon the _Thames_) very high Tydes. But a
good _Diary_ of the Height and time both of High-water, and Low-water, for
a year or two together, even at _Chatham_, or _Greenwich_; but rather at
some place in the _open_ Sea, or at the _Lands end_ in _Cornwal_, or on the
_West parts of Ireland_; or at St. _Hellens_, or the _Bermodas_, &c. would
do more to the resolving of this point, than any verbal discourse without
it.

3. To the third Objection, _That supposing the Earth and Moon to move about
a Common center of gravity; if that the highest Tydes be at the New-moon,
when the moon being nearest to the Sun, the Earth is farthest from it, and
its compound motion at the swiftest; and that the Tydes abate as the Earth
approacheth nearer; till it comes into the supposed Circle of her Annual
motion: It may be demanded, why do they not still abate as the Earth comes
yet nearer to the Sun; and the_ {284} _swiftnesse of its compound motion
still slackens? And so, why have we not Spring tides at the New Moon (when
the motion is swiftest) and Neap tides at Full Moon (when the motion is
slowest) but Spring tides at both?_ The answer (if observed) is already
given in my _Hypothesis_ it self. Because the effect is indifferently to
follow, either upon a suddain Acceleration, or a suddain Retardation. (Like
as a loose thing, lying on a moving body; if the body be thrust suddainly
forward, that loose thing is cast back, or rather left behind, not having
yet obtained an equal _impetus_ with that of the body, on which it lyes;
but if stopped, or notably retarded, that loose incumbent is thrown
forward, by its formerly contracted _impetus_ not yet qualified or
accomodated to the slowness of the Body, on which it lyes.) Now both of
these happening, the one at the New Moon, the other at the Full Moon, do
cause high Tides at both.

4. To the fourth Objection, _That the highest Tydes are not at all places,
about the New Moon and Full Moon; and particularly, that, in some places of
the East Indies, the Highest Tydes are at the Quadratures_: I must first
answer in _general_; That as to the particular varieties of Tydes in
several parts of the World, I cannot pretend to give a satisfactory
account, for want of a competent History of Tydes, &c. Because (as is
intimated in what I wrote in the _general_) the various positions of
Chanels, Bays, Promontories, Gulfs, Shallows, Currents, Trade-winds, &c.
must needs make an innumerable variety of Accidents in particular places,
of which no satisfactory account is to be given from the general
_Hypothesis_ (though never so true) without a due consideration of all
those. Which is a task too great for me to undertake, being so ill
furnished with materials for it. And then as to the particular instance of
some places in the _East Indies_, where the highest Tydes are at the
_Quadratures_: I suppose, it may be chiefly intended of those about
_Cambaia_, and _Pegu_. At which places, beside that they are situate at the
inmost parts of Vast Bayes, or Gulfs (as they are called) they have also
vast In-draughts of some hundred Miles within Land; which when the Tydes
are out, do lye (in a manner) quite dry: And may therefore very well be
supposed to participate the effect of the Menstrual Tydes many dayes after
the {285} cause of them happens in the open Sea, upon a like ground as in
Straights and narrow Channels the Diurnall Tydes happen some hours later
than in the Ocean. And a like account must be given of particular accidents
in other places, from the particular situation of those places, as _Bays_,
_Chanels_, _Currents_, &c.

5. To the 5. Objection, _That the Spring-Tydes happen not, with us, just at
the Full and Change, but two or three daies after_. I should with the more
confidence attempt an Answer, were I certain, whether it be so in the
_Open_ Seas, or onely in our Channels. For the Answers will not be the same
in both cases. If onely in our Channels, where the Tydes find a large
in-draught; but not in the Open Seas: we must seek the reason of it from
the particular position of these places. But if it be so generally in the
wide Open Seas: We must then seek a reason of it from the general
Hypothesis. And, till I know the matter of Fact, I know not well, which to
offer at; lest whilst I attempt to salve one, I should fall foul of the
other. I know that Marriners use to speak of Spring-Tydes at the New and
Full of the Moon; though I have still had a suspition that it might be some
daies after, as well in the open Seas, as in our narrower Channels; (and
therefore I have chosen to say, in my Papers, _About_ the New and Full,
rather than _At_ the New and Full; and even when I do say _At_, I intend it
in that laxer sense in which I suppose the Marriners are to be understood,
for _Neer_ that time:) Of which suspition you will find some intimations
even in my first Papers: But this though I can admit; yet, because I was
not sure of it, I durst not build upon it. The truth is, the Flux and
Reflux of water in a vessel, by reason of the jogging of it, though it
follow thereupon; yet is, for the most part, discernable some time after.
For there must, upon that jog, be some time for Motion, before the
Accumulation can have made a Tyde. And so I do not know but that we must
allow it in all the Periods. For as the _menstrual_ High Tyde, is not (at
least with us) till some Daies after the Full and Change; so is the
_Diurnal_ High water, about as many Hours, after the Moons comming to
South; (I mean, At Sea: for in Chanels it varies to all Hours, according as
they are neerer or further from the open Sea:) And the _Annual_ High-Tydes
of _November_ and _February_; somewhat later than {286} (what I conjecture
to be from the same causes) the greatest Inequalities of the natural Days,
happening in _January_ and _October_. But this though I can admit, yet
(till I am sure of the matter of Fact) I do not build upon. And since it
hath hitherto been the custome to speak with that laxness of expression;
assigning the times of New-moon, Full-moon, and Quadratures, with the Moons
comming to South, for, what is neer those times: I did not think myself
obliged in my conjectural Hypothesis (while it is yet but a _Candidate_) to
speak more nicely. If the Hypothesis for the maine of it be found Rational;
the Niceties of it are to be adjusted, in time, from particular
Observation.

Having thus given you some Answers to the Objections you signifie to have
been made by several persons to my Hypothesis, and that in the same order
your Paper presents them to me; I shall next give you some account of the
two _Books_, which you advised me to consult; so far as seems necessary to
this business; Which, upon your intimation, I have since perused, though
before I had not.

And first, as to that of _Isaac Vossius, De motu Marium & Ventorum_; Though
I do not concur with him in his Hypothesis; That all the _Great motions of
the Seas_, &c. should arise onely from _so small a warming of the water_ as
to raise it (where most of all) _not a Foot_ in perpendicular, (as in his
12_th_ Chapter.) Or that there is no other connexion between the Moons
motion, and the Tydes _menstrual_ period, than a _casual Synchronism_
(which seems to be the doctrine of his 16_th_ and 18_th_ Chapters;) Beside
many other things in his Philosophy, which I cannot allow: Yet I am well
enough pleased with what is Historical in it, of the matter of Fact:
Especially if I may be secure, that he is therein accurate and candid, not
wresting the _Phænomena_ to his own purpose. But I find nothing in it,
which doth induce me to vary from my Hypothesis. For, granting his
Historicals to be all true; the account of the constant Current of the Sea
Westward, and of the constant Eastern Blasts, &c. within the _Tropicks_, is
much more plausibly, and (I suppose) truly rendered by _Galilæo_ long
since, from the Earths _Diurnal_ motion: (which, neare the _Æquator_,
describing a greater Circle, than nearer the {287} _Poles_, makes the
Current to be there more conspicuous and swift, and consequently, the Eddy,
or recurrent motion, nearer the Poles, where this is, more remiss:) than
can easily be rendered by so small a Tumor, as he supposeth. Not to adde;
that his account of the Progressive motion, which he fansieth to follow
upon this Tumefaction, and by Acceleration to grow to so great a height
near the Shoar (as in Chap. 13. and 14.) is a Notion, which seems to me too
extravagant to be salved by any laws of _Staticks_. And that of the Moons
motion onely Synchronizing with the Tydes, casually, without any _Physical_
connexion; I can very hardly assent to. For it can hardly be imagined, that
any such constant _Synchronisme_ should be in Nature; but where, either the
one is the cause of the other, or both depend upon some _Common_ cause. And
where we see so fair a foundation for a _Physical_ connection. I am not
prone to ascribe it to an Independent Sychronism. In sum; His History doth
well enough agree with my Hypothesis; and I think, the Phænomena are much
better salved by mine, than his.

And then as to _Gassendus_, in his discourse _De Æstu Maris_; I find him,
after the relating of many other Opinions concerning the Cause of it,
inclining to that of _Galilæo_, ascribing it to the Acceleration &
Retardation of the Earths motion, compounded of the Annual and Diurnal; And
moreover attempting to give an account of the _Menstrual Periods_ from the
Earths carrying the Moon about it self, as _Jupiter_ doth his _Satellites_;
which together with them is carryed about by the _Sun_, as one Aggregate;
(and that the Earth with its Moon is to be supposed in like manner to be
carried about by the Sun, as one Aggregate, cannot be reasonably doubted,
by those who entertain the _Copernican Hypothesis_, and do allow the same
of _Jupiter_ and his _Satellites_.) But though he would thus have the Earth
and Moon looked upon as two parts of the same moved Aggregate, yet he doth
still suppose (as _Galilæo_ had done before him) that the line of the Mean
Motion of this Aggregate (or, as he calls, _motus æquabilis et veluti
medius_) is described by the _Center_ of the _Earth_ (about which Center he
supposeth both its own revolution to be made, and an Epicycle described by
the Moons motion;) not by another Point, distinct from the Centers of both,
about which, as the {288} common Center of Gravity, as well that of the
Earth, as that of the Moon, are to describe several Epicycles. And, for
that Reason fails of giving any clear account of this _Menstrual_ Period.
(And in like manner, he proposeth the Consideration as well of the Earths
_Aphelium_ and _Perihelium_ as of the _Æquinoctial_ and _Solstitial_
Points, in order to the finding a Reason of the _Annual_ Vicissitudes; but
doth not fix upon any thing, in which himself can Acquiesce: And therefore
leaves it _in medio_ as he found it.)

It had been more agreeable to the Laws of _Staticks_, if he had, (as I do,)
so considered the _Earth_ and _Moon_ as two parts of the same movable, (not
so, as he doth, _aliam in Centro et sequentem præcise revolutionem axis,
aliam remotius ac velut in circumferentia_, but,) so, as to make neither of
them the Center, but both out of it, describing Epicycles about it: Like
as, when a long stick thrown in the Air, whose one end is heavyer than the
other, is whirled about, so as that the End, which did first fly foremost,
becomes hindmost; the proper line of motion of this whole Body is not that,
which is described by either End, but that, which is described by a middle
point between them; about which point each end, in whirling, describes an
Epicycle. And indeed, in the present case, it is not the Epicycle described
by the Moon, but that, described by the Earth, which gives the _Menstrual_
Vicissitudes of motion to the Water; which would, as to this, be the same,
if the Earth so move, whether there were any Moon to move or not; nor would
the Moons Motion, supposing the Earth to hold on its own course, any whit
concern the motion of the Water.

[Illustration]

But now, (after all our Physical, or Statical Considerations) the clearest
Evidence for this Hypothesis (if it can be had) will be from Celestial
Observations. As for instance; (see _Fig._ 5.) Supposing the Sun at S; the
Earths place in its Annual Orb at T; and _Mars_ (in opposition to the Sun,
or near it) at M: From whence _Mars_ should appear in the Zodiack at
[gamma], and will at Full moon be seen there to be; the Moon being at C and
the Earth at c; (and the like at the New-moon.) But if the Moon be in the
First quarter at A, and the Earth at a: _Mars_ will be seen, not at
[gamma], but at [alpha]; too slow: And when the Moon is at B, and the Earth
at b, _Mars_ will be seen at [beta]; yet too slow: till at the {289}
Full-moon, the Moon at C, the Earth at c, _Mars_ will be seen at [gamma],
its true place, as if the Earth were at T. But then, after the Full, the
Moon at D, the Earth at d; _Mars_ will be seen, not at [gamma], but at
[delta], too forward: and yet more, when the Moon (at the last Quarter) is
at E, the Earth at e, and _Mars_ seen at [epsilon]. If therefore _Mars_
(when in opposition to the Sun) be found (all other allowances being made)
somewhat too backward before the Full moon, and somewhat too forward after
the Full-moon, (and most of all, at the Quadratures:) it will be the best
confirmation of the Hypothesis. (The like may be fitted to _Mars_ in other
positions, _mutatis mutandis_; and so for the other Planets.)

But this proof, is of like nature as that of the Parallaxis of the Earths
Annual Orb to prove the Copernican Hypothesis. If it can be observed, it
proves the Affirmative; but if it cannot be observed, it doth not convince
the Negative, but only proves that the Semidiameter of the Earths Epicycle
is so small as not to make any discernable Parallax. And indeed, I doubt,
that will be the issue. For the Semidiameter of this Epicycle, being little
more than the Semidiameter of the Earth it self, or about 1-1/3 thereof (as
is conjectured, in the _Hypothesis_, from the Magnitudes and Distances of
the Earth and Moon compared;) and there having not as yet been observed any
discernable _Parallax_ of _Mars_, even in his neerest position to the
Earth; it is very suspicious, that here it may prove so too. And whether
any of the other Planets will be more favourable in this point, I cannot
say.

       *       *       *       *       *

_ANIMADVERSIONS of Dr. _Wallis_, upon Mr. _Hobs_'s late Book, _De
Principiis & Ratiocinatione Geometrarum_._

These were communicated by way of Letter, written in _Oxford_, July 24.
1666. to an Acquaintance of the _Author_, as follows:

Since I saw you last, I have read over Mr. _Hobs_'s Book _Contra Geometras_
(or _De Principiis & Ratiocinatione Geometrarum_) which you then shewed me.
A New Book of _Old_ matter: Containing but a _Repetition_ of what he had
before told us, more than once; and which hath been Answered long agoe.

In which, though there be Faults enough to offer ample {290} matter for a
large Confutation; yet I am scarce inclined to believe, that any will
bestow so much pains upon it. For, if that be true, which (in his
_Preface_) he saith of himself, _Aut solus insanio Ego, aut solus non
insanio_: it would either be _Needless_, or _to no Purpose_. For, by his
own confession, _All others_, if they be not mad themselves, ought to think
_Him_ so: And therefore, as to _Them_ a Confutation would be _needless_;
who, its like, are well enough satisfied already: at least out of danger of
being seduced. And, as to himself, it would be _to no purpose_. For, if
_He_ be the Mad man, it is not to be hoped that he will be convinced by
Reason: Or, if _All We_ be so; we are in no capacity to attempt it.

But there is yet another Reason, why I think it not to need a Confutation.
Because what is in it, hath been sufficiently confuted already; (and, so
Effectually; as that he professeth himself not to Hope, that _This Age_ is
like to give sentence for him; what ever _Nondum imbuta Posteritas_ may
do.) Nor doth there appear any Reason, why he should again Repeat it,
unless he can hope, That, what was at first False, may by oft Repeating,
become True.

I shall therefore, instead of a large Answer, onely give you a brief
Account, _what is in it_; &, _where it hath been already Answered_.

The chief of what he hath to say, in his first 10 Chapters, against
_Euclids_ Definitions, amounts but to this, That he thinks, _Euclide_ ought
to have allowed his _Point_ some _Bigness_; his _Line_, some _Breadth_; and
his _Surface_, some _Thickness_.

But where in his _Dialogues_, pag. 151, 152. he solemnly undertakes to
Demonstrate it; (for it is there, his 41th _Proposition_:) his
Demonstration amounts to no more but this; That, _unless a Line be allowed
some Latitude; it is not possible that his Quadratures can be True_. For
finding himself reduced to these inconveniences; 1. That his _Geometrical
Constructions_, would not consist with _Arithmetical calculations_, nor
with what _Archimedes_ and others have long since demonstrated: 2. That the
_Arch_ of a Circle must be allowed to be sometimes _Shorter_ than its
_Chord_, and sometimes _longer_ than its _Tangent_: 3. That the same
Straight Line must be allowed, at one place onely to _Touch_, and at
another place to _Cut_ the same Circle: (with others of like nature;) He
findes it necessary, that these things may not seem Absurd, to allow his
_Lines_ some _Breadth_, (that so, as he speaks, _While a Straight Line with
its Out-side doth at one place {291} Touch the Circle, it may with its
In-side at another place Cut it_, &c.) But I shou'd sooner take this to be
a _Confutation of His Quadratures_, than a _demonstration of the Breadth of
a _(Mathematical)_ Line_. Of which, see my _Hobbius Heauton-timorumenus_,
from _pag._ 114. to p. 119.

And what he now Adds, being to this purpose; That though _Euclid_'s [Greek:
Sêmeion], which we translate, _a Point_, be not indeed _Nomen Quanti_; yet
cannot this be actually represented by any thing, but what will have some
Magnitude; nor can _a Painter_, no not _Apelles_ himself, draw a _Line_ so
small, but that it will have some Breadth; nor can _Thread_ be spun so
Fine, but that it will have some Bigness; (_pag._ 2, 3, 19, 21.) is nothing
to the Business; For _Euclide_ doth not speak either of such _Points_, or
of such _Lines_.

He should rather have considered of his own Expedient, _pag._ 11. That,
when one of his (_broad_) Lines, passing through one of his (_great_)
Points, is supposed to cut another Line proposed, into two equal parts; we
are to understand, the _Middle of the breadth_ of that Line, passing
through the _middle_ of that Point, to distinguish the Line given into two
equal parts. And he should then have considered further, that _Euclide_, by
a _Line_, means no more than what Mr. _Hobs_ would call _the middle of the
breadth_ of his; and _Euclide_'s _Point_, is but the _Middle_ of Mr.
_Hobs_'s. And then, for the same reason, that Mr. _Hobs_'s _Middle_ must be
said to have no _Magnitude_; (For else, not the _whole Middle_, but the
_Middle of the Middle_, will be _in the Middle_: And, the _Whole_ will not
be equal to its _Two Halves_; but Bigger than _Both_, by so much as the
_Middle_ comes to:) _Euclide_'s _Lines_ must as well be said to have no
Breadth; and his _Points_ no Bigness.

In like manner, When _Euclide_ and others do make the _Terme_ or _End_ of a
Line, a _Point_: If this _Point_ have _Parts_ or _Greatness_, then not the
_Point_, but the _Outer-Half_ of this Point ends the Line, (for, that the
_Inner-Half_ of that Point is not at the End, is manifest, because the
_Outer-Half_ is beyond it:) And again, if that _Outer Half_ have _Parts_
also; not this, but the _Outer_ part of it, and again the _Outer part_ of
that _Outer part_, (and so in _infinitum_.) So that, as long as _Any thing
of Line_ remains, we are not yet at the _End_: And consequently, if we must
have passed the _whole Length_, before we be at the _End_; then that _End_
(or _Punctum terminans_) has _nothing of Length_; (for, when the _whole
Length_ is past, there is nothing of it left.) And if Mr. _Hobs_ tells us
(as _pag._ 3.) that this {292} _End_ is not _Punctum_, but only _Signum_
(which he does allow _non esse nomen Quanti_) even _this_ will serve our
turn well enough. _Euclid_'s [Greek: Sêmeion], which some Interpreters
render by _Signum_, others have thought fit (with _Tully_) to call
_Punctum_: But if Mr. _Hobs_ like not that name, we will not contend about
it. Let it be _Punctum_, or let it be _Signum_ (or, if he please, he may
call it _Vexillum_.) But then he is to remember, that this is only a
Controversie in _Grammar_, not in _Mathematicks_: And his Book should have
been intitled _Contra Grammaticos_, not, _Contra Geometras_. Nor is it
_Euclide_, but _Cicero_, that is concern'd, in rendring the Greek [Greek:
Sêmeion] by the Latine _Punctum_, not by Mr. _Hobs_'s _Signum_. The
Mathematician is equally content with either word.

What he saith here, _Chap._ 8. & 19. (and in his fifth _Dial._ p. 105. &c.)
concerning the _Angle of Contact_; amounts but to thus much, That, by the
_Angle of Contact_, he doth not mean either what _Euclide_ calls an
_Angle_, or any thing of that kind; (and therefore says nothing to the
purpose of what was in controversie between _Clavius_ and _Peletarius_,
when he says, that _An Angle of Contact hath some magnitude_:) But, that by
the _Angle of Contact_, he understands the _Crookedness of the Arch_; and
in saying, the _Angle of Contact hath some magnitude_, his meaning is, that
the _Arch of a Circle hath some crookedness_, or, is a _crooked line_: and
that, of equal Arches, That is the more crooked, whose chord is shortest:
which I think none will deny; (for who ever doubted, but that a _circular
Arch is crooked_? or, that, of such Arches, equal in length, _That is the
more crooked, whose ends by bowing are brought nearest together_?) But, why
the _Crookedness of an Arch_, should be called an _Angle of Contact_, I
know no other reason, but, because Mr. _Hobs_ loves to call that _Chalk_,
which others call _Cheese_. Of this see my _Hobbius Heauton-timorumenus_,
from _pag._ 88. to p. 100.

What he saith here of _Rations_ or _Proportions_, and their _Calculus_; for
8. Chapters together, (_Chap._ 11. _&c,_) is but the same for substance,
what he had formerly said in his 4th. Dialogue, and elsewhere. To which you
may see a full Answer, in my _Hobbius Heauton-tim._ from _pag._ 49. to p.
88. which I need not here repeat.

Onely (as a _Specimen_ of Mr. _Hobs_'s Candour, in Falsifications) you may
by the way observe, how he deals a Demonstration of Mr. _Rook_'s, in
confutation of Mr. _Hobs_'s Duplication of the Cube. Which when he had
repeated, _pag._ 43. He doth then (that it might seem absurd) change those
words, _æquales {293} quatuor cubis_ DV; (_pag._ 43. _line_ 33.) into these
(p. 44. l. 5.) _æqualia quatuor Lineis, nempe quadruplus Recta_ DV: And
would thence perswade you, that Mr. _Rook_ had assigned a _Solide_, equal
to a _Line_. But Mr. _Rook's_ Demonstration was clear enough without Mr.
_Hobse's_ Comment. Nor do I know any Mathematician (unless you take _Mr.
Hobs_ to be one) who thinks that _a Line multiplyed by a Number will make a
Square_; (what ever _Mr. Hobs_ is pleased to teach us.) But, That _a Number
multiplyed by a Number, may make a Square Number_; and, That _a Line drawn
into a Line may make a Square Figure_, _Mr. Hobs_ (if he were, what he
would be thought to be) might have known before now. Or, (if he had not
before known it) he might have learned, (by what I shew him upon a like
occasion, in my _Hob. Heaut._ _pag._ 142. 143. 144.) _How_ to understand
that language, without an Absurdity.

Just in the same manner he doth, in the next page, deal with _Clavius_, for
having given us his words, pag. 45 l. 3. 4. _Dico hanc Lineam
Perpendicularem extra circulum cadere_ (because neither _intra Circulum_,
nor in _Peripherea_;) He doth, when he would shew an errour, first make
one, by falsifying his word, _line_ 15. where instead of _Lineam
Perpendicularem_, he substitutes _Punctum A._ As if _Euclide_ or _Clavius_
had denyed the _Point A._ (the utmost point of the _Radius_,) to be in the
Circumference: Or, as if Mr. _Hobs_, by proving the _Point A._ to be in the
Circumference, had thereby proved, that the _Perpendicular Tangent A E_ had
also lyen in the Circumference of the Circle. But this is a Trade, which
Mr. _Hobs_ doth drive so often, as if he were as well faulty in his
_Morals_, as in his _Mathematicks_.

The _Quadrature of a Circle_, which here he gives us, _Chap._ 20. 21. 23.
is one of those _Twelve_ of his, which in my _Hobbius Heauton-timorumenus_
(from _pag._ 104. to _pag._ 119) are already confuted: And is the _Ninth_
in order (as I there rank them) which is particularly considered, _pag._
106. 107. 108. I call it _One_, because he takes it so to be; though it
might as well be called _Two_. For, as there, so here, it consisteth of
_Two branches_, which are Both false; and each overthrow the other. For if
the _Arch of a Quadrant_ be equal to the _Aggregate of the Semidiameter and
of the Tangent of 30. Degrees_, (as he would _Here_ have it, in _Chap._ 20.
and _There_, in the close of _Prop._ 27;) Then is it not equal to _that
Line, Whose Square is equal to Ten squares of the Semiradius_, (as,
_There_, he would have it, in _Prop._ 28. and, _Here_, in _Chap. 23._) And
if it be equal to _This_, then not to _That_. For _This_, and _That_, are
not equal: As I then demonstrated; and need not now repeat it.

The grand Fault of his Demonstration (_Chap._ 20.) wherewith he would now
New vamp his old false quadrature, lyes in those Words _Page_ 49. _line_
30, 31. _Quod Impossibile est nisi _ba_ transeat per _c_._ which is no
impossibility at all. For though he first bid us _draw the Line R c_, and
afterwards the _Line R d_; Yet, Because he hath no where proved (nor is it
true) that _these two are the same Line_; (that is, that the point _d_ lyes
in the _Line R c_, or that _R c_ passeth through _d_:) His proving that _R
d cuts off from _ab_ a Line equal to the Sine of R c_, doth not prove, that
_ab_ passeth through _c_: For this it may well do though _ab_ lye _under
c._ (vid. in case _d_ lye beyond the line _R c._ that is, further from
_A_:) And therefore, unless he first prove (which he cannot do) that _A c_
( a sixth part of _A D_) doth just reach to the line _R c_ and no further,
he only proves {294} that a sixth part of _ab_ is _equal_ to the Sine of
_B c_. But, whether it _lye above it_, or _below_ it, or (as Mr. _Hobs_
would have it) just _upon_ it; this argument doth not conclude. (And
therefore _Hugenius's_ assertion, which Mr. _Hobs_, _Chap._ 21. would have
give way to this Demonstration, doth, notwithstanding this, remain safe
enough.)

His demonstration of _Chap._ 23. (where he would prove, that _the aggregate
of the Radius and of the Tangent of 30. Degrees_ is equal to _a Line, whose
square is equal to 10 Squares of the Semiradius_;) is confuted not only by
me, (in the place forecited, where this is proved to be impossible;) but by
himself also, in this same Chap. _pag._ 59. (where he proves sufficiently
and doth confesse, that this demonstration, and the 47. _Prop._ of the
first of _Euclide_, cannot be both true.) But, (which is worst of all;)
whether _Euclid's_ Proposition be False or True, his demonstration must
needs be False. for he is in this Dilemma: If that Proposition be _True_,
his demonstration is _False_, for he grants that they cannot be both True,
_page_ 59 _line_ 21. 22. And again, if that Proposition be False, his
Demonstration is so too; for _This_ depends upon _That_, _page_ 55. _line_
22. and therefore must fall with it.

But the Fault is obvious in _His Demonstration_ (not in _Euclid's
Proposition_:) the grand Fault of it (though there are more) lyes in those
words, _page_ 56. _line_ 26. _Erit ergo M O minus quam M R_ Where, instead
of _minus_, he should have said _majus_. And when he hath mended that
Error, he will find, that the _major_ in _page_ 56. _line penult_, will
very well agree with _majorem_ in _page_ 57. _line_ 4 (where the _Printer_
hath already mended the Fault to his hand) and then the _Falsum ergo_ will
vanish.

His Section of an Angle _in ratione data_, _Chap._ 22 hath no other
foundation, than his supposed _Quadrature_ of _Chap._ 20. And therefore,
that being false, this must fall with it. It is just the same with that of
his 6. Dialogue, _Prop._ 46. which (besides that it wants a foundation) how
absurd it is, I have already shewed, in my _Hobbius Heauton-timor._ _page_
119. 120.

His _Appendix_, wherein he undertakes to shew a Method of finding _any
number of mean Proportionals, between two Lines given_: Depends upon the
supposed Truth of his 22. Chapter; about _Dividing an Arch in any
proportion given_: (As himself professeth: and as is evident by the
Construction; which supposeth such a Section.) And therefore, that failing,
this falls with it.

And yet this is other wise faulty, though _that_ should be supposed True.
For, In the first Demonstration; _page_ 67. _line_ 12. _Producta L f
incidet in I_; is not proved, nor doth it follow from his _Quoniam igitur_.

In the second Demonstration; _page_ 68. _line_ 34. 35. _Recta L f incidit
in x_; is not proved; nor doth it follow from his _Quare_.

In his third Demonstration; _page_ 71: _line_ 7. _Producta _Y P_ transibit
per _M_;_ is said _gratis_; nor is any proof offered for it. And so this
whole structure falls to the ground. And withall, the _Prop._ 47. _El._ 1
doth still stand fast (which he tells us, _page_ 59, 61, 78. must have
Fallen, if his Demonstrations had stood:) And so, _Geometry_ and
_Arithmetick_ do still agree, which (he tells us, _page_ 78: _line_ 10.)
had otherwise been at odds.

And this (though much more might have been said,) is as much as need to be
said against that Piece.

       *       *       *       *       *


Printed with Licence for _John Martyn_, and _James Allestry_, Printers to
the Royal Society.

{295}

       *       *       *       *       *




_Num._ 17.

PHILOSOPHICAL
_TRANSACTIONS._

       *       *       *       *       *

_Munday_, _Septemb._ 9. 1666.

       *       *       *       *       *

The Contents.

    _Observations made in several places (at _London_, _Madrid_ and
    _Paris_,) of the late _Eclipse of the Sun_, which hapned _June_ 22.
    1666. Some Enquiries and Directions, concerning _Tides_, proposed by
    _Dr. Wallis_. Considerations and Enquiries touching the same Argument,
    suggested by Sir _Robert Moray_. An Account of several Books lately
    publish't: Vid. 1. _Johannis Hevelii Descriptio Cometæ,_ A. 1665.
    exorti; una cum _Mantissa Prodromi Cometici_. 2. _Isaacus Vossius de
    Nili & aliorum Fluminum Origine_. 3. _Le Discernement du Corps & de
    l'Ame_, par Monsieur de _Cordemoy_._

       *       *       *       *       *

_Observations made in several places, Of the late _Eclipse of the Sun_,
which hapned on the 22 of _June_, 1666._

The Observations that were made at _London_ by Mr. _Willughby_, Dr. _Pope_,
Mr. _Hook_, and Mr. _Philips_, are these:

             The Eclipse began at 5h. 43'                    h. '
           { 3/11 diam.        at 6.  00     | 5 dig.     at 7. 06
           {    4 digits       at 6.  07     | 4 dig.     at 7. 13
   It was  {    5 dig.         at 6.  13     | 3 dig.     at 7. 20
   darkned,{    6 dig.         at 6.  21     | 2 dig.     at 7. 26
           {    7 dig.         at 6.  39½    | 1 dig.     at 7. 32
           {    6 dig.         at 6.  57     | 0 dig.     at 7. 37

Its _Duration_ hence appears to have been one hour and 54 m. Its _greatest
Obscurity_ somewhat more than 7. digits. About the middle, between the
Perpendicular and Westward Horizontal _Radius_ the Sun, viewing it through
Mr. _Boyle_'s 60. foot-_Telescope_, there was perceived a little of the
Limb of the Moon without the Diske of the Sun: which seemed to some of the
Observers to come from some shining _Atmosphere_ about the Body either of
the Sun or Moon.

They affirm to have observ'd the _Figure_ of this _Eclipse_, and measured
the {296} _Digits_, by casting the _Figure_ through a 5 foot _Telescope_,
on an extended paper, fix't at a certain distance from the Eye-glasse, and
having a round figure; all whose _Diameters_ were divided, by 6
_Concentrick_ Circles, into 12 _Digits_.



The Observations made at _Madrid_ by a Noble Member of the _Royal Society_,
His Excellence the Earle of _Sandwich_, as they were sent to the Right
Honourable, the Lord Vice-Count _Brounker_, are these;

The Eclipse _began_ at _Madrid_ about 5 of the Clock in the morning, at 5
h. 15', the Suns _Altitude_ was 6 deg. 55'.

The _Middle_ of it was at 6 h. 2', the Suns _Altitude_, 15. deg. 5'.

The _End_ was exactly at 7 h. 5'; the Suns _Altitude_, 25. deg. 24'.

The _Duration_, 2h. 4'.

37. Parts of the Suns diameter remained light.

63. Parts of the same were darkened.



The Observations made at _Paris_ by Monsieur _Payen_, assisted by several
_Astronomers_, as they were printed in _French_, and addressed to Monsieur
de _Montmor_, are these;

The _Eclipse_ began there, at 5 h. 44'. 52". _mane_. It ended at 7 h. 43'.
6". So that its _whole Duration_ was 1 h. 58'. 14". The _greatest
Obscuration_ they assign to have been 7. dig. 50. m. but they adde, that it
seem'd to have been greater by 3 minuts; which M. _Payen_ imputes to a
particular motion of _libration_ of the Suns Globe, which entertain'd that
Luminary in the same _Phasis_ for the space of 8. _min._ and some
_seconds_, as if it had been stopped in the midst of its Course; rather
than to a tremulous Motion of the _Atmosphere_, as _Scheiner_ would have
it.

They intimate that they took the time of each _Phasis_ from half _digit_ to
half _digit_, as well by a _Pendulum_, as by the _Altitudes_ of the _Suns
Center_ above the _Horizon_, corrected by the _Verticall Paralaxes_ and
_Æstivall Refractions_, by which they judged, that though the Time by the
_Pendulum_ may be sufficient for _Mechanicall_ Operations, yet 'tis not
exact enough for establishing the _Grounds of true Astronomy_.

They further conceive that the apparent _Diameters_ were almost equal;
seeing that in the _Phasis_ of 6. _Digits_, the _Circumference_ of the
_Moons disk_ passed through the _Center_ of that of the _Sun_, so as that
two Lines drawn through the two _Horns_ of the Sun, made with the _Common
Semi-diameter_ two _Equilateral Triangles_.

Next, they affirm, That there was so great a Variation in the _Parallaxes_,
by reason as well of the Refractions of the Air, which environs the Earth,
as of the Alteration of the Air, which encompasses the Moon, that the
_Horns_ of the Sun, there formed by the Shaddow of the Moon, appeared in
all kinds of _Figures_; Sometimes inclined to the _Vertical_, sometimes
_Perpendicular_ to the _Horizon_, and at last _Parallel_; the _Convexe_
part respecting the _Heaven_, and the _Concave_, the _Horizon_. By the
crossing (_so they go on_) of the {297} _Horns_ with the _Angles of
Inclination_, it will be easie to those, that have exactly observed them,
and that are skill'd in the higher _Astronomical_ Calculations, to compute
the _true Place_ of the _Moon_ in her _Orbite_, that so it may be compared
with that of the _Tables_, and with that, which has been observ'd in other
places, for the more precise determinating of the _Difference_ of
_Meridians_ (that being the way, esteem'd by _Kepler_ the most certain) and
for making a good Judgment of the defect or exactnesse of the Celestial
_Tables_.

Then they observe, That the _Beginning_ and the _Middle_ of this _Eclipse_
hapned to be in the _North Eastern Hemisphere_, and the _End_, in the
_South-Eastern_. The _first Contact_ (as 'twere) of the two Disks was
observ'd in the _Superior Limb_ of the _Suns Disk_ in respect to the
_Vertical Line_, and in the _Inferior_ in respect to the _Ecliptick_: But
the _Middle_, and the _End_ were seen in the _Superior Limb_, in respect
both to the _Vertical_ and the _Ecliptick_: And (what to this Author seems
extraordinary) both the _Beginning_ and the _End_ of this _Eclipse_ hapned
to be in the _Oriental_ part of the Suns Disk.

Lastly, they take notice, that by their Observations it appears, that there
is but little exactness in all the _Astronomical Tables_, predicting the
_Quantity_, _Beginning_ and _Duration_ of this Eclipse; Those of
_Lansbergius_ importing, That the Obscuration should be of 10. dig. 48';
those of _Ricciolo_, of 9. dig. 1'; and those of _Kepler_, of 7. dig. 30'.
16": Again, that the _Duration_ should be of 2h. 2'. Lastly, The
_Beginning_ did anticipate the _Ricciolan Tables_ by 5 _minuts_, the _End_
by 23; and the _Middle_, almost by 11. In the mean time the Author notes,
that the _Rudolphin Tables_ come nearest to the Truth; and withal assures
the _Reader_ of the goodnesse of the _Instruments_ employed in his
_Observations_, and of the singular care, he, together with his skilful
Assistants, took in making them.

       *       *       *       *       *

_Some Inquiries and Directions concerning _Tides_, proposed by Dr.
_Wallis_, for the proving, or disproving of his lately publish't
_Discourse_ concerning them_.

The Inquisitive Dr. _Wallis_, having in his lately printed _Hypothesis_ of
Tides intimated, that he had reason to believe, that the _Annual
Spring-tides_ happen to be rather about the beginnings of _Febr._ and
_Nov._ than the two _Æquinoxes_, doth in a late Letter to the _Publisher_,
written from _Oxford_ in _Aug._ last, desire, that some understanding
Persons at _London_, or _Greenwich_, but rather nearer the Sea, or upon the
Sea-shore, would make _particular_ Observation of all the _Spring-Tides_
(_New-Moon_ and _Full-Moon_) between this and the End of _November_; and
take account of the _Hour_, and of the _Perpendicular height_: that we may
see, whether those in _September_, or those of _November_ be highest: And
it were not amiss, the Low waters were observed too. Which may be easily
done by a mark made upon any standing Post in the Water, by any {298}
Water-man, or other understanding Person, who dwells by the Water-side.

It would also deserve (thinks he) to be inquired into, whether, when the
Tides be highest, the Ebbs be ever lowest, & _contra_; (which is generally
affirmed, and almost put out of question) or rather (which sutes best with
this _Hypothesis_) whether, when the Tides are highest, both in the
_Annual_ and _Menstrual_ Periods, the Low waters be not also highest; and
at Neap Tides, the Ebbes also very low.

He adds, that he should expect, that the Spring Tides now coming, and those
at the beginning of _September_, should not be so high, as those at the
_middle_ of _September_; and then lower again at the _beginning_ of
_October_, and after that, higher at the _middle_ of _October_, and higher
yet about the _beginning_ of _November_ (at the usual times of
_Spring-tides_ after the _New_ and _Full_.)

       *       *       *       *       *

_Considerations and Enquiries concerning _Tides_, by Sir _Robert Moray_;
likewise for a further search into Dr. _Wallis's_ newly publish't
_Hypothesis_._

In regard that the High and Low waters are observed to increase, and
decrease regularly at several seasons, according to the Moons age, so as,
about the _New_ and _Full Moon_, or within two or three daies after, in the
Western parts of _Europe_, the _Tides_ are at the _highest_, and about the
_Quarter-Moons_, at the _lowest_, (the former call'd _Spring-tides_, the
other _Neap-tides_;) and that according to the height and excesses of the
_Tides_, the _Ebbes_ in opposition are answerable to them, the heighest
Tide having the lowest Ebbe, and the lowest Ebbe, the highest Tide; the
Tides from the _Quarter_ to the _highest Spring-tide_ increasing in a
certain proportion; and from the _Spring tide_ to the _Quarter-tide_
decreasing in like proportion, as is supposed: And also the _Ebbes_ rising
and falling constantly after the same manner: It is wished, that it may be
inquired, in what proportion these Increases and Decreases, Risings and
Fallings happen to be in regard of one another?

And 'tis supposed, upon some Observations, made in fit places, by the
above-mentioned Gentleman, though, (as himself acknowledges) not thoroughly
and exactly performed, that the Increase of the Tides is made in the
_Proportion_ of _Sines_; the first Increase exceeding the lowest in a small
proportion; the next in a greater; the third greater than that; and so on
to the mid-most, whereof the excess is greatest, diminishing again from
that, to the highest Spring-Tide; so as the proportions, before and after
the _Middle_, do greatly answer one another, or seem to do so. And
likewise, from the _highest Spring-tide_, to the _lowest Neap-tide_, the
_Decreases_ seem to keep the like proportions; the _Ebbes_ rising and
falling in like manner and in like proportions. All which is supposed to
fall out, when no Wind or other Accident causes an alteration. {299}

And whereas 'tis observed, that upon the main Sea-shore the Current of the
Ebbings and Flowings is sometimes swifter, and sometimes slacker, than at
others, so as in the beginning of the Floud the Tide moves faster but in a
small degree, increasing its swiftness constantly till towards the _Middle_
of the Floud; and then decreasing in velocity again from the _Middle_ till
to the top of the High water; it is supposed, that in Equal spaces of Time,
the Increase and Decrease of velocity, and consequently the degrees of the
Risings and Fallings of the same, in Equal spaces of time, are performed
according to the _Proportion_ of _Sines_.

But 'tis withall conceived, that the said _Proportion_ cannot hold
_exactly_ and _precisely_, in regard of the _Inequalities_, that fall out
in the _Periods_ of the _Tides_, which are commonly observed and believed
to follow certain _Positions_ of the _Moon_ in regard of the _Equinox_,
which are known not to keep a _precise_ and _constant_ Course: so that,
there not intervening equal portions of Time between one New Moon and
another, the Moons return to the same _Meridian_, cannot be alwaies
perform'd in the same Time; and consequently there must be a like Variation
of the Tides in the Velocity, and in the Risings and Fallings of the Tides,
as to equal spaces of time. And the Tides from New-moon to New-moon being
not alwaies the same in number, as sometimes but 57, sometimes 58, and
sometimes 59, (without any certain order of succession) is another evidence
of the difficulty of reducing this to any great exactness. Yet, because
'tis worth while, to learn as much of it, as may be, the _Proposer_ and
many others do desire, That Observations be constantly made of all these
Particulars for some Months, and, if it may be, years together. And because
such Observations will be the more easily and exactly made, where the Tides
rise highest, it is presumed, that a fit _Apparatus_ being made for the
purpose, they may be made about _Bristol_ or _Cheap-stow_, best of any
places in _England_, because the Tides are said thereabout to rise to ten
or twelve fathoms; as upon the coast of _Britanny_ in _France_, they do to
thirteen and fourteen.

In order to which, this following _Apparatus_ is proposed to be made use
of. In some convenient place upon a Wall, Rock, or Bridge, &c. let there be
an _Observatory_ standing, as neer as may be to the brink of the Sea, or
upon some wall; and if it cannot be well placed just where the Low water
is, there may be a Channel cut from the Low water to the bottom of the
Wall, Rock, &c. The Observatory is to be raised above the High water 18. or
20. foot; and a Pump, of any reasonable dimension, placed perpendicularly
by the Wall, reaching above the High water as high as conveniently may be.
Upon the top of the Pump a Pulley is to be fastned, for letting down into
the Pump a piece of floating wood, which, as the water comes in, may rise
and fall with it. And because the rising and falling of the water amounts
to 60. or 70. foot, the Counterpoise of the weight, that goes into the
Pump, is to hang upon as many Pulleys, as may serve to make it rise & fall
within the space, by which the height of the Pump exceeds the height of the
Water. And because by {300} this means the Counterpoise will rise and fall
slower; and consequently by less proportions, than the weight it self, the
first Pulley may have upon it a Wheele or two, to turn _Indexes_ at any
proportion required, so as to give the minute parts of the motion, and
degrees of risings and fallings. All which is to be observed by
_Pendulum-watches_, that have _Minutes_ and _Seconds_, with _Checks_,
according to Mr. _Hugens's_ way.

And because if the Hole, by which the water is let into the Pump, be as
large as the Bore of the Pump it self, the weight that is raised by the
water, will rise and fall with an Undulalation, according to the inequality
of the Sea's Surface, 'twill therefore be fit, that the Hole, by which the
water enters, be less than half as bigg as the Bore of the Pump; any
inconvenience that may follow thereupon, as to the Periods and Stations of
the Floud and Ebb, not being considerable.

And to the end, that it may appear the better; what are the _particular_
Observations, desired to be made, near _Bristol_ or _Cheap-stow_ bridg, it
was thought not amiss, to set them down distinctly by themselves.

1. The degrees of the Rising and Falling of the water every quarter of an
hour (or as often as conveniently may be) from the Periods of the Tides and
Ebbs; to be observed night and day, for 2 or 3 months.

2. The degrees of the velocity of the Motion of the Water every quarter of
an hour for some whole Tides together; to be observed by a second
_Pendul_-watch: and a logg fastened to a line of some 50 fathoms, wound
about a wheel.

3. The exact measures of the Heights of every utmost High-water and
Low-water, from one Spring-tide to another, for some Months or rather
Years.

4. The exact Heights of Spring-tides and Spring-Ebbs for some Years
together.

5. The Position of the Wind at every observation of the Tides; and the
times of its Changes; and the degrees of its Strength.

6. The State of the Weather, as to Rain, Hail, Mist, Haziness, &c, and the
times of its Changes.

7. At the times of observation of the Tides, the height of the
_Thermometer_; the height of the _Baroscope_; the height of the
_Hygroscope_; the Age of the Moon, and her _Azimuths_; and her place in all
respects; And lastly the _Sun's_ place; all these to _minutes_.

And it would be convenient, to keep _Journal Tables_, for all these
Observations, each answering to its day of the Month.

For the _Apparatus_ of all these observations, there will be particularly
necessary.

A good _Pendulum_-watch.

A _Vane_ shewing _Azimuths_ to minute parts.

An _Intrument_ to measure the Strength of the Winde.

A large and good _needle_ shewing _Azimuths_ to degrees. {301}

_Thermometers_, _Barometers_, _Hygroscopes_.

These Observations being thought very considerable as well as curious, 'tis
hoped, that those who have conveniency, will give encouragement and
assistance for the making of them; and withall oblige the publick by
imparting, what they shall have observed of this kind: The _Publisher_
intending, that when ever such observations shall be communicated to him,
he will give notice of it to the _publick_, and take care of the
improvement thereof to the best use and advantage. A _Pattern_ of the
_Table_, proposed to be made for observing the _Tides_, is intended to be
published the next opportunity, God permitting.

       *       *       *       *       *

_An Account of Several Books lately published_

I. _Johannis Hevelii DESCRIPTIO COMETÆ, Anno Æræ Christianæ MDCLXV. exorti;
unà cum MANTISSA Prodromi Cometici, Observationes omnes prioris COMETÆ
MDCLIV, ex iisque genuinum motum accuratè deductum, cum Notis &
Animadversionibus, exhibens._

This Book (as the Title it self intimates) undertakes two things. _First_,
To give an Account of the _Second_ of the two late Comets, which appeared,
when the _other_ was scarce extinct; Concerning which, the Author doth,
from the Observations made by himself with a _Sextant_ of 6 foot, and
divided into _minutes_ and _seconds_, assign _both_ its true place (as well
in respect of the _Ecliptick_ as the _Æquator_) _and_ its proper motion;
Adding a fair Delineation of its Course, together with the genuine
Representations of its _Head_ and _Train_, in each day of its apparition;
and subjoyning a General Description and Discourse of some of the more
notable _Phenomena_ thereof. It was first seen at _Dantzick_ by the
Watchmen, the 5th of _April_ st. n. 1665. and then observed by the _Author_
from _April_ 6, about 1½ of the Clock in the morning, till _April_ 20 at 3.
in the morning. During which time, it went with a reasonable velocity;
making 46 deg. in its Orb, _according to the Order of the Signs_, moving
from the _Breast_ of _Pegasus_, towards the _Head_ of _Andromeda_, and the
_Left Horn_ of _Aries_; having, as 'tis presumed, taken its rise from above
_Sagittary_, and run through the _Breast_ of _Antinous_, under _Aquila_ and
the _Dolphin_, to the said _Pegasus_; and so on, as is already expressed.

The _Head_ of it is in the Book described of a Colour like that of
_Jupiter_, all along much brighter than that of the former Comet, though of
a somewhat less magnitude; having in its middle onely _one_ round, but very
bright and big _Kernel_ or Speck, resplendent like Gold, and encompassed
with another more dilute and seemingly uniform matter: its _Tail_ being at
first, about 17. deg. and afterwards 20. and sometimes 25 deg. long, and
divaricated towards the End.

_Next_, it is observed, that though this Star did afterwards slacken its
pace, yet it retained the vividness of its Colour, both of the _Head_ and
_Train_; the _Head_ especially, keeping at the time as well of the last
observations, as of the {302} first, the brightness of its single _kernel_,
though the environing more dilute matter were then almost all lost; it
being, according to the Author, more and more attenuated, and grown narrow,
the nearer the Star approached to the Sun.

_Thirdly_, 'tis noted, That this _Comet_ did very much digress from the
_Hypothesis_, delivered by _M. Auzout_, in regard that, whereas according
to that _Hypothesis_, this Star should not arrive to the _Ecliptick_ till
after the space of 3 months, it arrived there the 28 of _April_. And then,
that its first Conjunction with the Sun hapned between the 19 and 20 of
_April_, and the second, the last of _April_, not (as _M. Auzout_, would
have it) the 15 of _May_. So that he concludes, that this Comet never came
down to the _Pleiads_ and the _Eye of Taurus_, as the Hypothesis of _M.
Auzout_ requires, but that from _April_ 20. it did immediately take its
course towards the Ecliptick, deflecting every day more and more from the
_Section_ of a _Great Circle_, to the _Lucida_ of _Aries_, arriving at the
_Ecliptick_ the last of _April_, about the 8th or 10th deg. of _Taurus_;
not in _July_ about the 8th of _Gemini_, and the _Eye of Taurus_.

_Fourthly_, He intimates, that if this Comet had appeared some weeks
sooner, it would have confronted the former Comet, being yet in its vigour
and of a conspicuous bigness, in the same place, where that was, viz. the
_Head of Aries_.

_Fifthly_, He observes, that this Star in progress of time became
_Retrograde_, whence it came to pass, that in the Months of _June_ and
_July_ it did not appear again before the Rising of the Sun, though the Sun
left it far behind: whereas, if it had proceeded toward the _Eye of
Taurus_, it would have appeared again in the morning.

_Sixthly_, He maintains, that this Comet was not the same with the former;
which he thinks may be demonstrated, onely by a due Delineation of both
their Course upon the _Globe_; where he saith it to be evident, that the
former could never come to the _Head_ of _Pegasus_, as moving already in
_February_ in a streight Course about the _Head_ of _Aries_; Besides, that
the _former_ went in the very beginning in a _Retrograde_ motion; but
_this_ perpetually in a direct one: _that_, about the end, very slow, its
Head lessning and growing dark; _this_ swift enough, with its head
conspicuous and bright. To which he adds, that the whole Course of the
former was made under a quite different _Angle_ of the _Orbite_ and
_Ecliptick_, and a different Motion of the _Nodes_ from the latter: As also
that their _Faces_ differed very much from one another; the _first_
exhibiting all along a matter, which as to its density and rarity, altered
from day to day exceedingly, whereas the _second_ retained (to the Authors
admiration, who affirms, never to have observed the like) all the time he
saw it, one and the same round, dense and bright Speck or Kernel.

All which he concludes 1, With an Intimation of his sense concerning two
other Comets, pretended to have been lately seen, _One_ at _Rome_, about
the {303} _Girdle of Andromeda_, in the Months of _February_ and _March_,
1664. the other in _Germany_ in _Capricorne_, about _Saturne_ in the head
of _Sagittary_, during the Months of _September_ and _October_, 1665. 2ly,
With an Advertisement of what he has done in that important Work for the
Advancement of _Astronomy_, the due _Restitution of the Fixt Stars, vid._
That he has almost finish't it; himself alone, without trusting to any
other mans labour, that was not directed by him.

The _Second_ Part of this Book (the _Mantissa_ to the _Prodromus
Cometicus_) endeavours to justifie the Authors Observations touching the
former Comet, excepted against by M. _Auzout_, in several particulars; as
1. That it had not pass'd to the _First_, but _Second_ Star in _Aries_, and
had mov'd in quite another Line, than He had described. 2. That its _proper
motion_ about the end of _January_ and the beginning of _February_, 1665.
had not been rightly assigned. 3. That the _Bignesse_ of its _Diameter_ had
not been truly delivered; Nor 4. The _Faces_ of its _Head_ in due manner
represented.

To all which the Author endeavors to answer: 1. By delivering all his
Observations of that Comet, thereby to shew, what care and diligence he had
used, _particularly_ to make out, how great its _Diurnal motion_ had been;
in what proportion, and how far, it decreased, and where and in what degree
it increased again: Which being, as he conceives, duly and exactly deduced,
and demonstrated, he esteems it afterwards to be easie for every one,
versed in these matters, certainly to collect and to judge, what way the
Comet, after it became invisible to the naked Eye, and could be no longer
observed with _Sextants_ and _Quadrants_, had taken, and what Line it had
described. 2, By subjecting all those Observations, with great diligence
and labour, to a rigid _Calculus_, thereby to obtain, for every day, the
_Longitudes_, _Latitudes_, _Right Ascensions, Declinations_, _Proper
motion_, _Angle_ of the _Ecliptick_ and the _Æquator_, and the _Nodes_ of
that Comet; for the construction of an _Ephemerides_ of its whole Motion.
From all which he pretends to prove, that he has not erred in his
Observation of _February_ 18, nor been prepossest by any _Hypothesis_, nor
deluded by any _Fixt Star_, as M. _Auzout_ thinketh; but that near the
_First Star_ of _Aries_ there _then_ appear'd a _Phænomenon_, most like to
that Comet, that was seen some dayes before, if compared with the
Observations make thereof _Febr._ 12, 13, 14. Though he will not hitherto
positively determine, whether that _Phænomenon_, which appear'd to him
_February_ 18. was {304} indeed that very Comet, which he saw with his
naked Eye, and observed with his Geometrical Instruments, the said 12, 13,
and 14. dayes of _February_; or whether it was another, and whether he had
lost that Comet, which moved towards the _Second Star_ in _Aries_: but
leaves it to the Learned World, and particularly to the _Royal Society_,
after they shall have well examined and considered all his Observations,
and the _Calculus_ raised therefrom, to judge of this, and the other
particulars in controversie.



II. _Isaacus Vossius de NILI et ALIORUM FLUMINUM ORIGINE_. It was _Numb._
14. of these _Transactions_, that gave an account of the _Cause_ of the
_Inundation of the Nile_, as it was rendred by Monsieur _de la Chambre_:
_This_ is to give you another, not only of the _Inundation_, but also of
the _Origine_ of that, and of _other Rivers_, as it is delivered by
Monsieur _Isaac Vossius_, who undertakes in this Book to shew;

1. That those _Subterraneous Channels_, through which several
_Philosophers_ teach, that the Sea discharges it self into the Rivers, are
not only imaginary, but useless, in regard 'tis impossible for the water to
rise from the Subterraneous places up to the Mountains, where commonly the
Sources of Rivers are.

2. He explicates, why, if a Pipe be put into a Bason full of Water, the
water is seen more raised in the Pipe, than in the Bason, and rises higher
according as the Pipe is narrower; On the contrary, if the same Pipe be put
into a Bason full of Quicksilver, the Quicksilver stayes lower in the Pipe,
than in the Bason. The reason, which he renders hereof, is, That as the
Water sticks easily to all it touches, it is sustain'd by the sides of the
narrow Pipe wherein it is included: And indeed, if the Pipe be quite drawn
out of the Water, the Water doth not all fall out, but so much of it
remains, as the sides of the Pipe could sustaine: Whence it is, that the
Water which is kept up by the Walls of the Tube, weighing no longer upon
that which is in the Bason, is thrust upwards, and keeps it self raised
above its Levell; but the Quicksilver not adhering so easily, as Water, to
Bodies it touches, is not sustained by the sides of the Tube, and so mounts
not above its Levell, but rather descends below it, because the Pipe, which
is streight, hinders the endeavor that is in the _Mercury_ to rise to its
Level. He adds, that this Observation makes nothing for the Explication of
the _Origine of Rivers_; because, though it be true, that the Water {305}
by this means rises above its Levell, yet it does never run out at the top
of the Pipe. Having said this, he answers to the other Arguments, commonly
alledged to maintain this Opinion.

3. He pretends, that all Rivers proceed from a _Colluvies_ or _Rendevous_
of Rain-waters, and that, as the Water, that falls upon _Hills_, gathers
more easily together, than that which falls in _Plaines_, therefore it is,
that Rivers ordinarily take their Source from _Hills_. Thence also comes it
(saies he) that there are more _Rivers_, than _Torrents_, in the _Temperate
Zones_; and, on the contrary, more _Torrents_, than _Rivers_, in the
_Torrid Zone_: For, as in hot Climats the Mountains are far higher, the
Water, that descends from them with impetuosity, runs away in a little
while, and formes such Collections of Water, as soon dry up, but in cold
Climats, the Waters do not run away but slowly, and are renew'd and
recruited by Rain, before they are quite dryed up; because the Hills are
there lower, and so the Bed of Rivers hath lesse declivity.

Having thus discoursed of _Rivers_ in _General_, he treats of the _Nile_ in
_particular_; and there

1. Observes, That the Order of the Seasons of the Year is quite inverted
under the _Torrid Zone_. For, whereas it should be then Summer, when the
Sun is near; and Winter, when the Sun is farther off: Under the _Torrid
Zone_ 'tis never lesse hot, than when the Sun is nearest; nor more hot,
than when the Sun is farthest off: So that to the people that live between
the _Æquinoctial_ and the _Tropicks_, Summer begins about _Christmass_, and
their Winter, about St. _Johns_ day. The reason whereof is, (_saith he_)
that when the Sun is directly over their Heads, it raises abundance of
vapors, and draws them so high, that they are presently converted into
Water by the coldnesse of the Air; whence it comes to passe, that then it
rains continually, which does refresh the Air; but when the Sun is farther
off, there falls no more rain, and so the Heat becomes insupportable.

2. He proves by many recent Relations, that the _Sources_ of the _Nile_ are
on this side of the _Æquinoctial_ in _Æthiopia_, of which he gives a very
accurate _Mappe_, correcting many faults which _Geographers_ are wont to
commit in the Description of the Kingdom of the _Abyssins_, which they
believe to be much greater than indeed it is. {306}

3. This supposed, he easily gives an account, why the _Nile_ yearly
overflows about the end of _June_: For, as at that time there falls much
rain in _Æthiopia_, it must needs be, that the _Nile_, whose source is in
that Country, should then overflow, when those rains begin, and subside,
when they cease.

There are besides, in this Book, two other _Tracts_. In the _first_, M.
_Vossins_ endeavours to maintain the Doctrine, he had deliver'd in his Book
_De Lumine_, and to shew, that the _Soul_ of Animals is nothing but _Fire_,
that there are no invisible Atoms; nor so much as any Pores, even in the
Skin of man. Here he treats also of _Refractions_, and alledges the
Examples of several persons, who have then seen the Sun by the means of
Refraction, when really He was under the _Horizon_.

In the _second_, He discourses of some points of the _Mechanicks_; and
relates among other things, that the _Arrows_ and _battering Rams (Aries)_
of the Antients did as much execution, as our _Muskets_ and _Canons_; and
then, that the Vehemence of the percussion depends as much upon the Length
of the percutient Body, as upon the velocity of the Motion. He adds, that
the Length of a Canon ought not to exceed 13 foot, and that a greater
length is not onely useless, but hinders also the effect of the Gun, not
because the Bullet is thrown out of the Gun, before all the powder is fired
(as some believe;) but because the Bullet is then beaten back into the Gun
by the Air, re-entring into it with impetuosity, when the flame is extinct.



III. _LE DISCERNEMENT DU CORPS ET DE L'AME_, par M. _de Cordemoy_.

This _French_ Treatise (but very lately come to the _Publisher's_ hands)
examines the different Operations of the Soul and Body, and the Secret of
their Union, pretending to discover to every one, what he is, and what is
transacting within him. It consists of six Discourses.

[Sidenote: * _It sounds hard, To say, An _extended_ substance is
_indivisible_._]

1. In the _first_, the Author examines the Notions, we have in _general_ of
_Bodies_ and _Matter_; of _Quantity_; of _Qualities_; of _Place_; of
_Rest_; of _Motion_; of _Vacuity_; of _Forms_: to shew what is to be
understood by these Terms, which cause all the perplexity that is in the
ordinary _Physicks_. He begins with taking notice, that hitherto
_Philosophers_ have had no _distinct_ notions of _Bodies_ and _Matter_,
from the want whereof he conceives, that almost all the Errors in Common
_Physiology_ have {307} sprung. To rectify which, he defines _Bodies_ to be
* _Extended Substances_, and _Matter_ an _Aggregate of Bodies_. Whence he
inferrs, that _Bodies_ are Indivisible and _Matter_ divisible; a _Body_
being nothing but _one_ and the _same_ substance, whose different
extremities are inseparable, because they are the extremities of one and
the same Extension, and, in a word, of one and the same Substance; but
_Matter_ being nothing but an Association or Collection of Bodies, 'tis
evident, (_saith he_) it must be divisible. This doctrine he so much
insists upon, that he conceives, Nature cannot subsist, if a Body in the
sence he takes it, be divisible; and that _Motion_ and _Rest_ cannot be
explicated without it. As for _Quantity_, he makes that to be nothing but
More or Less Bodies; not allowing, that each Body should be a Quantity,
though it be a part of Quantity; no more than an _Unite_ is a Number,
though it make part of a Number: so that _Quantity_ and _Extension_ are two
distinct things with him, the _first_ belonging properly to _Matter_, the
last to a _Body_. Touching _Vacuity_, he conceives, that the Bodies, which
compose a mass, are not every where so near one another, as not to leave
some interval in several places. Neither does he think it necessary, that
those intervals should be fill'd up; nor unconceivable, that there should
be no Body between two Bodies; which touch not one another. And when 'tis
said, that those intervals cannot be conceived without Extension, and that
consequently there are Bodies that replenish them, he frankly pronounces
that not to be true; and affirms, that though it may be said, that between
two Bodies, which touch not one another, other Bodies may be placed of so
or so many feet, &c: yet ought it not to be inferred, that therefore they
_are_ there, but onely, that they are thus placed, that there _may_ be put
between them so many Bodies, as joyned together would compose an Extension
of so many feet. So that one conceives onely, that Bodies _may_ be placed
there, but not that they _are_ there: and as we can have an _Idea_ of many
Bodies, though none of them be in being; so we can conceive, that some
Bodies _may_ be put between others, where really there are none. And when
'tis alledged, that if all the Bodies, that fill a vessel full, were
destroyed, the sides of the vessel would be closed together; He professes,
he understands not that ratiocination, nor can conceive, what one Body does
to the subsistence of another, more than to sustain themselves mutually,
when they are thrust by the neighbouring ones: and therefore sees not, why
the sides of the vessel should close, if nothing did thrust them together;
but understands clearly, that two Bodies may well subsist so far from one
another, that one might place a great many Bodies between them, or none at
all, and yet they neither approach to, not recoil from one another. {308}

2. In the _Second_, he examines the _Changes_, which he knows in Matter,
and makes it his business to explicate all those that respect _Quantity_,
_Qualities_ and _Forms_, by _Local Motion_, esteeming that needs no other.

3. In the _third_, he explains the Motion of _Artificial_ Engins, and that
of _Natural_ ones, by one and the same Cause; endeavouring among other
things to shew, that the Body of an Animal is moved after the same manner
with a Watch. That cause of motion he makes the _Materia Subtilis_; and the
finer or subtiler that is, the better and fitter he conceives it to be to
preserve Motion.

4. In the _Fourth_, he teaches, that though Experience seems to evince,
that the Soul moves the Body, and that one Body moves an other; yet there
is nothing but God, that can produce any notion in the World, and all other
Agents, which we believe to be the _Cause_ of this or that Motion, are no
more but the _Occasion_ thereof. In doing this, he advances certain
_Axioms_, and Conclusions, which are in short,

a. The _Axioms_: That no substance has that of it self, which it can loose,
without ceasing to be, what it is: That every body may loose of its motion,
till it have no more left, without ceasing to be a Body: That we cannot
conceive but two sorts of substances, _vid._ a _Spirit_ (or _That which
thinketh_) and a _Body_, wherefore they must be considered as the Causes of
all, that happens, and what cannot proceed from the one, must necessarily
be adscribed to the other: That to _Move_, or to cause motion, is an
Action: That an Action cannot be continued but by the Agent, who began it.

b. The _Conclusions_: That no _Body_ hath Motion of it self: That the First
Mover of Bodies not a Body: That it cannot be but a _Spirit_, that is the
First Mover: That it cannot be but the same Spirit, who has begun to move
Bodies, that continues to move.

In the _Fifth_, He treats of the Union of the Body and Soul, and the
manner, how they act one upon the other; and esteems it not more difficult
to conceive the Action of Spirits upon Bodies, and of Bodies upon Spirits,
than to conceive the Action of Bodies upon Bodies: the cause of the great
difficulty in understanding the two former, arising (according to him) from
thence, that we will conceive the one by the other, not considering, that
every thing acting according to its own nature, we shall never know the
action of one Agent, if we will examine it by the notions we have of
another, that is of a quite differing nature. Here he notes, that the
Action of Bodies upon Bodies is not {309} more known to us; than that of
Spirits upon Bodies, or of Bodies upon Spirits; and yet most men admire
nothing but _this_, believing to know the _other_; whereas he Judges, that
all things being well examin'd, the Action of Bodies upon Bodies is no more
conceivable, than that of Spirits upon Bodies. Mean while the opinion of
the Authour touching this subject, is, That the union of Soul and Body
consists onely in this, that certain motions of the Body are followed by
certain _Cogitations_ of the Soul, and, on the contrary, that certain
Thoughts of the Soul are follow'd by certain _Motions_ of the Body. And,
having supposed, that Bodies are said to act upon one another, when they
cause some change suitable to Extension; and Spirits to act upon one
another, when they cause some change suitable to a Thought; he infers, that
when a Body acts upon a Spirit, that cannot be by causing any change of
motion, of figure, or parts, as having none of all these; nor when a Spirit
acts upon a Body, that cannot be by producing any change of Thought, as
having none: But, when this Body, or its motion, or figure, or other thing,
depending upon its nature, can be perceived by a Spirit, so as, upon that
occasion, this Spirit has thoughts, it had not before, it may be said, that
the Body has acted upon this Spirit, for as much as it has caused all the
change in it, whereof it was capable according to its nature.

In the _Sixth_, After he hath shew'd, what is to be understood by what we
call _Soul_, and by what we call _Body_, he labours to make it out, that we
are much more assured of the Existence of the Soul, than of that of the
Body, which he conceives he can prove from hence, that we cannot doubt,
that we think, because even doubting is thinking; but one may doubt,
whether one has a body, for several reasons, which he alledges, and thinks
so cogent, that he concludes, it is not evident to him by the light of
reason, that he has a Body. But supposing, there be Bodies, he examines,
what are the Operations, that belong to the Soul, and what those, that
belong to the Body; and lastly, what those, that result from the Union of
both: And then explains, how all those operations are perform'd, and
particularly, _Sensation_; where he shews, that the Nerves, holding at one
end to the Brain, whereof they are but Allongations, and being at the other
end extended to the extremities of the Body; when an Object comes to touch
those exterior ends of the Nerves, the interior ones in the Brain are
presently shaken; and cause different sensations according to the
diversitie of Nerves, and the differing manner, in which they are shaken.
And to shew, that 'tis this shaking, that causes Sensation, he notes, that
if any thing shakes the interior parts of the Nerves, though the object be
absent, the Soul has presently the same {310} sensations, as it would have,
if it were present. As, if one should knock on's head forcibly against a
wall, the shaking, which the blow gives to the Brain, moving the interior
extremities of the Nerve, which causes the sensation of Light, the Soul has
the same sensation, which it would have, if it saw a thousand Candles: On
the contrary, if the interior extremities of the nerves are not shaken,
though the object be present, it causes no sensation; whence it comes, that
if a strong Ligature be made upon the middle of the Arm, and the hand be
then prickt, no pain is felt, because the shaking of the nerves that are
pricked, being stopped by the Ligature, cannot reach to the extremities of
the Nerves, that are within the Brain.

       *       *       *       *       *


_Advertisement._

The following _Errata_, left by the _Press_ in _Num._ 16, the _Reader_ is
desired thus to correct.

Page 269. lin 27. read, _motion of B above the Center; G. is also_, with a
_Semi-colon_ after the word _Center_. p. 274. l. 13, r. _it to do to the_.
p. 277. l. 24. r. _natural days_. p. 281. l. 16. r. _of his_. ib. l. 27. r.
_a notion_. p. 293. l. 4. r. _enough without_. ib. l. 43. r. _to the Sine
of_. p. 294. l. 1. r. _to the Sine of_.

       *       *       *       *       *


_LONDON_,

Printed for _John Martin_ and _James Alestry_, Printers to the Royal
Society. 1666.

{311}

       *       *       *       *       *




_Numb._ 18.

PHILOSOPHICAL
_TRANSACTIONS._

       *       *       *       *       *

_Munday_, _October_ 22. 1666.

       *       *       *       *       *

The Contents.

    __Patterns_ of the _Tables_ proposed to be made for _Observing of
    Tides_; promised in the next foregoing _Transactions_. Other
    _Inquiries_ touching the Sea. Some Considerations touching the
    _Parenchymous_ parts of the Body. Observables concerning
    _Petrification_. A Relation from _Paris_, of a kind of _Worms_, that
    eat out Stones. Some promiscuous Observations made in _Somersetshire_.
    A Problem for finding the Year of the _Julian Period_, by a new and
    very easie Method. An Account of some Books, not long since publish'd,
    which are, _1. Tentamina Physico-Theologica de Deo_, Authore _Samuele
    Parkero. 2. Honorati Fabri Tractatus duo; Prior, de Plantis et de
    Generatione Animalium; Posterior, de Homine. 3. Relation du Voyage de
    l'Evesque de Beryte, par la Turquie, la Perse, les Indes_, &c. per
    Monsieur de _Bourges_._

       *       *       *       *       *

__Patterns_ of the _Tables_ proposed to be made for _Observing of Tides_,
promised in the next foregoing _Transactions_; by Sir _Rob. Moray_._

In performance of what was promised in the last of these _Papers_ for
Observing the _Tides_, here are subjoyned _Patterns_ of the _Tables_ there
mentioned; _One_, for marking the _precise Time_ of the High waters and
Low-waters during one Month; that is, between _New_ and _New_ Moon, or
_Full_ and _Full_ Moon. The _other_, for marking the _Degrees_ of the
Risings and Fallings of the Water in _Equal_ spaces of Time, and the
_Velocity_ of its motion at _several_ heights: The _Degrees_ of _Heat_ and
_Cold, &c._

The _Times_, assigned in the _first_, to the High waters and Lowest Ebbs,
are taken out of Mr. _Wing_'s Almanack, for this present year 1666, as he
calculates them for the Month of _September_ for _London Bridge_. Only,
whereas he takes notice but of _one_ High-water for every day, _Here_ are
set {312} down the Times of the other, and the two Ebbs intervening, by
subdividing the _Differences_, he assignes between two Tides, equally
amongst them. In all which, though there may be Errors, that is not to be
considered, seeing the Dissein is to Correct and State the _Times_ of the
_Tides exactly_ by _Experiments_, after this method. Mr. _Wing_ states the
High waters to fall out at _London-Bridge_ constantly, when the Moon is 46.
deg. 30. min. to the _West-ward_ of the _Meridian_. For the Times, he marks
for them, are made up by adding every day 3. hours, 6 minutes, to those in
his _Table_ for knowing the Time of the Moons coming to the South.

The _First Table_ consists of _two_ Parts, and each part of _four Columns_.
The _first_ part marks the Tides and Ebbs from the day of the _New_-Moon to
its _Full_: The _other_, from the _Full_ to the next _New_. The _first
Column_ in both parts hath the day of the Month and Week; _M._ standing
every where for _Morning_ and _A._ for _Afternoon_. The _third_ column hath
the _Character_ of the day of the Week prefixt to the Hour and Minute of
the High-water, and answering to the day of the Month. The _last_ Column
hath the same for the time of Low-water, varying the _Character_ of the
day, as often as the low-water falls out more early than the High-water. In
this _Example_ between the said _New_ Moons there falls out in all just 57.
periods of the Tide or Flowing water, and 58. of the Ebb or Low water;
which numbers vary according to the Intervals of the Moons changes, but
with what constancy and exactness, is to be inquired after: Which whosoever
undertakes to do, may keep such a _Table_, as is here proposed, in a Book
by it self.

The _other_ Table doth in 9. _Columns_ comprehend the particular
Observations of the _Degrees_ of the Rising and falling of the Tides, and
the other things specified at the Tops of them: The _first_ Column marking
the Hour and Minut common to all the several Observations. Each hour is
divided in 3. equal Parts, that number of Observations being only pitch't
upon by way of _Example_: The numbers may else be varied at pleasure, when
other more frequent Observations are thought fit to be made, or when they
prove too frequent and laborious; though the most frequent are most
desirable, till competent information of all particulars be attained.

The _Rising_ of the Tide from Low-water to the highest pitcht of the full
Sea, is here supposed to be 60. foot: And the Degrees of its rising every
20. Minuts, to be in the _Proportion_ of _Sines_, The whole time of Flowing
supposed to be 6. hours. But this _Example_ will serve for marking the
_Spaces_ of the Increasing or Rising, as well as of the falling of the
water, in order to the investigation of their _Proportions_ to one another,
when the _Duration_ of the Tide exceeds 6. hours by any number of _minuts_,
as well as for just 6. hours; seeing they may be easily collected from any
Number of Observations; their precise Time and that of the Duration of the
waters Rising and Falling (that is, the just interval between the
High-Water and Low-water) being known: This Calculation by _Sines_, being
only set down as a _Conjecture_, flowing from Observations of the Motion of
the water in its Rising and Falling, {313} which seems to observe this or
some such like Proportion; which is supposed still to hold in _all_ Tides,
be the _Duration_ what it will; the Increase still continuing
proportionably till the very midle of the Hight and Duration, and
Decreasing afterwards in the same manner: Which whether it be so indeed or
not, is that, which is desired to be known.

There is the like Proportion here supposed to be in the _different degrees_
of the _Velocity_ of the Current of the Water after _Equal_ spaces of
Times, as in its Rising and Falling: And so it is markt in the _Third_
Column. But because the _true Velocity_ of the Current of the Water, raised
above the Levell 456/1000 of a foot, is unknown, it is by way of
Supposition set at Ten feet in one Minute of an Hour, which being once
stated, the rest distant from each other by the space of 20. Minutes of an
Hour, are set down according to the same _Proportions_ of _Sines_ before
suggested. It being supposed, that of the _Velocity_ of the Current of the
Tide, after it hath flowed 20 minuts of an hour, be such, as a Log of Wood
placed in the Water will move 10 foot in the space of one minute of time,
at the middle of the Tide it will in the like space of Time move 114 f.
276/1000, and so proportionably at other times: Which, howsoever these
Proportions shall be found by Experiments to fall out, may be not unworthy
of the pains and charges requisite to acquire the knowledge of it. For,
besides the satisfaction it may afford upon other accounts, it may possibly
be of no small use to those, who need an exact reckoning of their Ships
running, when the Velocity of the Current of the Tide may be necessary to
be known; lest through the defect of the knowledge of that, especially when
it is reckoned less than indeed it is, the Ship be thrown in the night upon
Shores, Rocks or Sands, when they reckon themselves to be far from them.

The Numbers in the 4, 5, 6, 7, and 8. _Columns_ are set down at random,
only for _Examples_ sake; there being no difficulty in the apprehension of
it, and imitating of it in setting down the true Hights and Variations of
the _Thermometer_, _Baroscope_, &c. The Use whereof is so vulgarly known,
that there needs no further Direction concerning them. But if any person
who would make these Experiments, do not know the fabrick or use of any of
the Instruments requisite for some of these Observations, nor where to have
them, he may address himself to Mr. _Shortgrave_, one of the _Operators_ of
the _Royal Society_, lodged in _Gresham Colledge_, from whom he will
receive full satisfaction about these things.

But the labour employed in the Observations of the Heat, Cold, &c. required
to be taken notice of in order to the Ends proposed in the former _Tract_,
and others that may be of no less delight than advantage, will be much
retrenched, when Dr. _Christopher Wren_ puts in practice, what he some
years ago proposed to the _Royal Society_ concerning an _Engine_ with a
_Clockwork_, which may perform these Observations in the last enumerate
_Columns_, without being toucht or lookt after but once or twice a day.

The Tables themselves follow,

{314}

_A Perpendicular Line divided into _Signes_, supposed to be the _Periods_
of the Risings and Fallings of the Tides, as is in the other Table
represented._

[Illustration]

  1666.     Age of       Time of High water.        Time of Low water.
  Sept.     the moon
            ho.mi.   Day. Hour. Min.         Day. Hour. Min.
  Mo.  3.   New       Mo.   2.  57.   Morn.   Mo.   9.  8.    Morn.
            8.38'.          3.  19. Aftern.         9.  30. Aftern.
  Tu.  4.             Tu.   3.  41.      M.   Tu.   9.  51½      M.
                            4.  2.       A.         10. 12½      A.
  We.  5.             We.   4.  23.      M.   We.   10. 33¼      M.
                            4.  43½      A.         10. 53¾      A.
  Th.  6.             Th.   5.  4.       M.   Th.   11. 14½      M.
                            5.  25.      A.         11. 35½      A.
  Fr.  7.             Fr.   5.  46.      M.   Fr.   11. 56½      M.
                            6.  7.       A.   Sa.   0.  17½      M.
  Sa.  8.             Sa.   6.  28.      M.         0.  39½      A.
                            6.  51.      A.   Su.   1.  2½       M.
  Su.  9.             Su.   7.  14.      M.         1.  23½      A.
                            7.  37.      A.   Mo.   1.  48¼      M.
  Mo.  10.            Mo.   8.  0.       M.         2.  13.      A.
                            8.  26.      A.   Tu.   2.  39.      M.
  Tu.  11.  1. Qu.    Tu.   8.  52.      M.         3.  5.       A.
            10 A.           9.  18.      A.   We.   3.  31.      M.
  Mo.  12.            Mo.   9.  44.      M.         3.  57¾      A.
                            10. 11½      A.   Th.   4.  25¼      M.
  Th.  13.            Th.   10. 39.      M.         4.  53.      A.
                            11. 7.       A.   Fr.   5.  21.      M.
  Fr.  14.            Fr.   11. 35.      M.         5.  49.      A.
  Sa.  15.            Sa.   0.  3.       M.   Sa.   6.  17.      M.
                            0.  31.      A.         6.  45.      A.
  Su.  16.            Su.   0.  59.      M.   Su.   7.  13.      M.
                            1.  27.      A.         7.  41.      A.
  Mo.  17.            Mo.   1.  55.      M.   Mo.   8.  9.       M.
                            2.  23.      A.         8.  36¾      A.

  Tu.  18.  Full.     Tu.   2.  50½      M.   Tu.   9.  4¼       M.
            11.10'.         3.  19.      A.         9.  31¼      A.
  We.  19.            We.   3.  45.      M.   We.   9.  58½      M.
                            4.  11.      A.         10. 25½      A.
  Th.  20.            Th.   4.  39.      M.   Th.   10. 52½      M.
                            5.  6.       A.         11. 20.      A.
  Fr.  21.            Fr.   5.  34.      M.   Fr.   11. 48.      M.
                            6.  2.       A.         0.  16.      A.
  Sa.  22.            Sa.   6.  30.      M.   Sa.   0.  44.      A.
                            6.  58.      A.   Su.   1.  12½      M.
  Su.  23.            Su.   7.  27.      M.         1.  41½      A.
                            7.  36.      A.   Mo.   2.  10¼      M.
  Mo.  24.            Mo.   8.  24½      M.         2.  38¾      A.
                            8.  53.      A.   Tu.   3.  6¾       M.
  Tu.  25.            Tu.   9.  20½      M.         3.  34¼      A.
                            9.  48.      A.   We.   4.  1¾       M.
  We.  26.  last Q    We.   10. 15½      M.         4.  29¼      A.
            3.11'           10. 43.      A.   Th.   4.  56½      M.
  Th.  27.            Th.   11. 10.      M.         5.  23½      A.
                            11. 37.      A.   Fr.   5.  48.      M.
  Fr.  28.            Fr.   11. 59.      M.         6.  10.      A.
  Sa.  29.            Sa.   0.  21.      M.   Sa.   6.  32.      M.
                            0.  43.      A.         6.  54.      A.
  Su.  30.            Su.   1.  5.       M.   Su.   7.  16.      M.
  Octob.                    1.  27.      A.         7.  38.      A.
  Mo.  1.             Mo.   1.  49.      M.   Mo.   7.  59.      M.
                            2.  9.       A.         8.  19.      A.
  Tu.  2.             Tu.   2.  29.      M.   Tu.   8.  39.      M.
            New.            2.  49.      A.         8.  59.      A.
  We.  3.   1.38'     We.   3.  9.       M.   We.   9.  19.      M.

  1666.      Rising, and        Thermo-           Hygro-
  Sept. 3.   fall of Tides      metre             scope
  Hour. M.   Foot  /1000        Inch /10          Inch /10
                      Velocity of        Baro-            Azimuth. Force
                      the Current        scope                of the Wind
                      Foot  /1000       Inch /10                deg. deg.
                      00,  000.
             0, 000.                                              Weather
  XII.  00.           00,  000.  6.  7.  28.  1.  3.  4.  S. to W.  50. 3.
             0, 456.                                           Rain great
        20.           10,  000.  6.  7.  28.  1.  3.  4.  S. to W.  57. 3.
             1, 353.                                           Rain great
        40.           36,  250.  6.  8.  28.  1.  3.  4.  S. to W.  60. 3.
             2, 211.                                           Rain small
  I.    00.           48,  587.  6.  8.  28.  1.  3.  3.  S. W.     45. 4.
             3, 000.                                           Rain small
        20.           66,  658.  6.  8.  28.  1.  3.  2.  S. W.     30. 4.
             3, 696.                                      Rain very small
        40.           81,  053.  6.  9.  28.  2.  3.  1.  S. W.     36. 4.
             4, 284.                                      Fair but cloudy
  II.   00.           93,  289.  6.  9.  28.  2.  3.  0.  S. W.     39. 5.
             4, 740.                                        Fair and warm
        20.           103, 289.  6.  8.  28.  1.  2.  7.  S. W.     42. 5.
             5, 049.                                      Warm and cloudy
        40.           110, 724.  6.  8.  28.  2.  2.  3.  S. W.     19. 6.
             5, 211.                                             Sunshine
  III.  00.           114, 276.  6.  8.  28.  2.  2.  0.  S. W.     60. 5.
             5, 211.                                   Sunshine and clear
        20.           110, 724.  6.  7.  28.  3.  2.  1.  S. W.     73. 5.
             5, 049.                                          Sun clouded
        40.           103, 289.  6.  7.  28.  3.  2.  0.  S. W.     90. 6.
             4, 740.                                               Cloudy
  IIII. 00.           93,  289.  6.  6.  28.  3.  2.  1.  S. W.     90. 6.
             4, 284.                                 Hazy about the Horiz.
        20.           81,  053.  6.  6.  28.  4.  2.  3.  N. W.     87. 6.
             3, 696.                                                Misty
        40.           66,  658.  6.  5.  28.  4.  2.  3.  N. W.     70. 7.
             3, 000.                                                Misty
  V.    00.           48,  487.  6.  4.  28.  4.  2.  3.  N. W.     59. 7.
             2, 211.                                          Clearing up
        20.           36,  250.  6.  2.  28.  5.  2.  3.  N. W.     50. 6.
             1, 353.                                                Clear
        40.           10,  000.  6.  1.  28.  5.  2.  1.  N. W.     60. 5.
             0, 456.                                             Sunshine
  VI.   00.           00,  000.  6.  0.  28.  5.  2.  0.  N. W.     60. 4.
             0, 000.                                             Sunshine

{315}

       *       *       *       *       *

_Other Inquiries Concerning the Sea._

The _Publisher_ of these _Tracts_, knowing that the Honorable _Robert
Boyle_ had not left unconsidered the Natural History of the _Sea_, of which
Subject the late, and these present Papers, have entertained the _Reader_
as to the Observables of its _Flux_ and _Reflux_; He was on this occasion
instant, with that Gentleman to impart to him, for publication, these Heads
of Inquiries, he had drawn up, touching that Subject: Which having obtained
(though the _Author_ desires, they may be lookt upon as unfinisht) he thus
subjoyns.

What is the Proportion of Salt, that is in the Water of differing Seas; And
whether in the same Sea it be always the same? And if it be not, how much
it differs?

[Sidenote: * _This last Clause containing difficult _Quaere_ and that may
seem something odd, Mr. _Boyl_ thinks fit to note, That having recommended
this matter, among others, to a learned Physician, that was sailing into
_America_, and furnished him with a small _Hydrostaticall_ Instrument, to
observe from time to time the Differences of Gravity he might meet with;
This account was returned him, That he found by the Glass, the Sea-water to
increase in weight, the nearer he came to the _Line_, till he arrived at a
certain Degree of _Latitude_; as he remembers, it was about the 30th; after
which, the Water seemed to retain the same specifick gravity, till he came
to the _Barbadoes_, or _Jamaica_._]

What is the Gravity of Sea-waters in reference to Fresh Waters and to one
another: Whether it vary not in Summer and Winter, and on other Scores? And
whether in the same Season its Gravity proceed _only_ from the greater or
lesser Proportion of Salt, that is in it, and not sometimes from other
Causes? And what are the differing Gravities of the Sea-water, according to
the Climats. *

What are the Odors, Colours and Tasts, observable in Sea-water?

What is the depth of the sea in several places, and the Order of its
increase and Decrements? And whether the Bottom of the Sea does always rise
towards the Shore, unless accidentally interrupted?

Of the Bottom of the Sea, and how it differs from the Surface of the Earth,
in reference to the Soyl, and evenness or Roughness of the Superficies, And
the Stones, Minerals and Vegetables to be found there?

What the Figuration of the Seas from North to South, and from East to West,
and in the several Hemispheres and Climats?

What communication there is of Seas by Streights and Subterraneal
Conveyances?

Of the Motion of the Sea by Winds, and how far Storms reach downwards
towards the Bottom of the Sea?

[Sidenote: * _The particulars whereof (saith the Author) are here omitted;
Sir _Robert Moray_ and Dr. _Wallis_ having by there more accurate inquiries
about _Tides_ made them needless._]

Of the grand Motions of the Bulk or Body of the Sea; especially of the
Tides *; Their History as to their Nature and Differences.

{316} What power the Sea hath to produce or hasten Putrefaction in some
Bodies, and to preserve others; as Wood, Cables, and others that are sunk
under it?

Of the Power ascribed to the Sea to eject Dead Bodies, _Succinum_,
_Ambergris_?

Of the shining of the Sea in the night?

What are the Medical vertues of the Sea, especially against _Hydrophobia_?

What is its vertue to Manure Land? And what are the Plants, that thrive
best with Sea-water.

       *       *       *       *       *

_Some Considerations concerning the _Parenchymous_ parts of the Body._

These were communicated by the inquisitive M. _Edmund King_ at the Instance
of the _Publisher_, as follows;

The _Parenchymous_ parts of the Body, are by _Anatomists_ generally
supposed to be in very many places wholly _void of Vessels_; designed
chiefly to fill up Cavities and interstices between the Vessels, and to
boulster up the same, and to convey them through the parts.

But having many years endeavoured to excarnate several parts of the Body,
_viz._ the Liver, Lungs, Spleen, Kidneys, &c. (not to name the _Placenta
Uteri_, which seems to be _Parenchymous_ too;) and being very desirous to
make a _Scheme_ of the Vessels of any of these, what ever they were, I fixt
upon; I found, notwithstanding all my care to preserve the Vessels, when I
was freeing them, as heedfully as I could, from the supposed _Parenchyma_,
that in every breach, I made, either with my fingers or otherwise, all my
endeavors were destructive to my purpose: and that, upon examination of
those bits, much of which is called _Parenchyma_, I met in them more
Vessels, than I had preserved in the parts whence they came: And though the
portion were never so small, yet my bare eye could make this discovery;
much more could I, when assisted by a _Microscope_, perceive, I had
destroyed more Vessels than preserved, in despite of the exactest care, I
was capable to use. And being not a little concern'd, that I should
undertake to preserve the Vessels by such a Cause, as I saw plainly to be
their definition (were the part never so big, or never so small) I was both
confounded and tired. For I saw (and so must any, that will attempt this
work) in my endeavouring to preserve one Vessel of a traceable magnitude, I
spoiled an infinite number of others less discernable, which were as truly
Vessels, as the other, differing only in size and figure (as to
appearance.) Then reviewing what mischief I had done in every place, quite
through the whole Tract of my Fingers, Knife, &c. I begin to think with my
self, That it was not impossible for these parts to consist wholly of
Vessels curiously wrought and interwoven (probably for more Uses, than is
yet known;) And the {317} consideration, which came into my mind, of a
piece of fine Cloth (which consists of so many several minute Hairs, call'd
_Wool_) was no discouragement to this opinion. Yet I durst not be
presumptuous as to indulge my self too much in it; much less to venter
presently to speak of such a thing, which seem'd to contradict so many
Learned Men's belief. But being restless, till I might receive more
satisfaction in the thing, I iterated experiments over and over; some of
which prov'd so successful to my apprehension, that I was encouraged in the
year 1663. and 1664 to discourse of it to several very worthy Persons, as
Mr. _Boyl_, Sir _William Petty_, Dr. _Williams_, Dr. _Lenthal_, Dr. _Jaspar
Needham_, Dr. _Samson_, (who afterwards sent me a Letter from _France_,
intimating the acquaintance he had made with the learned _Steno_, who hath
since published something of the same Discovery) Mr. _Daniel Cox_, and Dr.
_Samuel Parker_, &c, who doubtless cannot but remember, that then I related
to them, I found much cause to believe, that that substance commonly called
_Parenchyma_, was in most, if not in all its _Parenchymous_ parts, full of
Vessels; however it had been imagin'd by all, I could ever meet with, to
consist in great part of a substance, in many places void of Vessels,
designed for such uses, as are above mentioned.

Against which I have now further to alledge, 1. That I observe in a piece
of _Musculous_ flesh (so call'd) either raw, rosted, or boiled, &c. that if
I so far extend it as to make it to be seen through, I can (assisting my
Eye) perceive it full of Vessels placed as thick as is possible to be
imagin'd, (the fat if there be any, being first removed) there appearing
then nothing but vessels, yet so as with a _Microscope_ may be seen
through, when they are extended. 2. That, if any one, as he is at dinner,
take a piece of flesh, and begin either at the head or tail of a _Muscle_,
he may divide it _in infinitum_ all along from head to tail, without
breaking any thing of that, called Flesh, only these transverse _Fibres_,
that seem to stitch them together, and (as I am apt to think) pass through
the very Bodies of the smallest of them, and quite through the whole Muscle
up the Cutaneous porosities; so that there is not one of these small
_ducts_, that run _per longitudinem_, but 'tis furnisht with a sufficient
number of outlets, when need requires, though too minute to suffer any
_alimentary_ juice to pass transversly (in a living Body) or any other
liquor, when the Body is dead and cold. But to wave their use at present,
and to return to what I was saying. Compress between the fingers this bit
of flesh, and you shall find the Juice, especially if the Meat be Hot, to
go before your fingers toward either end you please; but if you compress
both ends, you shall see it swell into the middle; and again, if you press
the middle, it will run out at both ends. But further, suppose a piece of
flesh, called _Parenchyma_, as big, or as little as you please, in any part
of the Body, and let me prick it with a Needle, where you shall appoint; if
you feel it, I presume you will acknowledge, a _Nerve_, or a _Fibrilla_,
related to it, is touch'd; If you feel it not, I am sure some liquor either
sanguineous or other, will follow the Needle; And from whence can that
come, but out of Vessels? unless {318} accidentally, as by a _Contusion_,
&c., it be extravased, in which case my Argument will not be injured,
because the part is depraved, whereas I speak of the parts, as they are in
their natural State.

To confirm and illustrate all which, I desire, that the following
_familiar_ Observations may be considered:

1. If a Horse, fat and fair to look on, without a hollow to be seen between
his Muscles, be rid extreme hard, and into a great sweat, and then kept one
day without water or moist meat, you shall see him took so thin in many
places as in the _musculous_ parts, that you will hardly believe it to be
the same Horse, especially if he be (as the Phrase is among Horse-masters)
a _Nash_ or _Wash-Horse_. The cause of which thinness will easily be
granted to be only an exhaustion of Juice, expended out of the Blood, which
did stuff out these Vessels. And whoever, that is used to ride hard, shall
observe, how thick this foul Horse breaths, and at what a rate he will reek
and sweat, will not much wonder at the alteration. But if the Horse be a
hardy one, and used to be hard ridden, then you will see, that one days
rest, and his belly full of good meat and drink, will in one day or two
almost restore him to his former plight, the food being within that short
space of time so distributed, that all the Vessels will be replenish'd
again, as before. And the cleaner the Horse is, the sooner recruited, and
the less sign of hard riding will appear. This seems to shew the facility,
with which the Juice, called Blood, passeth; Which surely, if there were
such a thing as a _Parenchyma_ might by several accidents (not difficult to
mention) be so deprav'd in several parts of it, that it might lose its
receptive faculty; than which it may be thought to have none of greater
use, being supposed to be without Vessels.

2. Discoursing sometimes with _Grasiers_ in the Country, about the Pasture
of Cattle, I have been informed by them, that, if they buy any Old Beasts,
Oxen, or Cows to feed, they choose rather those that are as poor as can be,
so they be sound; because that, if they are pretty well in flesh, what they
then add to them by a good pasture, though it make them both look and sell
well, yet it will not make them eat so well, their flesh proving hard and
very tough: Which some may suppose to be the age of _Parenchyma_; and so it
is of that so called. But if those Beasts be old and extremely poor, then
they feed very kindly, and will be not only very fat but spend well, like
young ones, and eat very tender.

Of which I take the reason (excluding a _Parenchyma_ now) to be this. When
an Oxe or a Cow is grown old, and in an indifferent plight as to his
_flesh_ (for so it is called) all those Vessels having been kept at that
size for the most part, have contracted a tenseness and firmness, and their
_fibers_ less extensive, nor so fitted for the reception of more unctuous
particles to relaxe them; and that additional unctuous matter, which
occasions fatness, is forced to seek new quarter any where (often remote
from Muscles) where it can be with least difficulty received; sometimes to
one place, sometimes to {319} another, as may be seen in Shambles. Whereas,
if there were such a thing as a _Parenchyma_, that certainly would, like a
hungry Sponge, immediately swell up in several parts, (which without much
difficulty might be discover'd in the dissection) and more eminently, where
it should find the pores most potent: And in the dissection of such Muscles
it would be very strange, not to find some, if not many, pieces of them in
various shapes, to the great inconvenience of the parts, in which they are
seated: Which yet I confess I could never find in any Muscle unless it were
where there had been a _Contusion_, or an _Impostume_, or the like. But
according to my opinion of the _Parenchymous_ parts, the reason, why the
Flesh of a very lean Ox or Cow, that hath got new Flesh in a good pasture,
eats tenderer, seems to be this: That in a very lean Beast the Vessels
designed for admitting and distributing the nourishing Juice, are so near
contracted, and lye so close together; that, when once they are relax'd; by
fresh and unctuous nourishment, they extend every way in all _extensive_
parts, until in a short time the whole Creature is, as it were, created a
new, having got new flesh upon old bones. And the necessity of extreme
extension makes all those parts, that are, as has been said, for the
admission of nourishment, so thin and fine, that it will make the lean
Beast, put into a rich pasture, eat young and tender: Whereas one of the
same Age, that never was very poor, fed in the same pasture, shall eat hard
and tough.

3. It has been observed, that Corpulent Persons in some Diseases, that
seize on them, do fall away to wonder, not only in the Wast, but in the
Arms, Legs, and Thighs; and the very Calves of the Legs have been observed
so flaccid and loose, that one might wrap the skin about the bones. The
reason whereof, according to the opinion deliver'd, may be easily rendred
to be, A great Consumption of the Stock of Liquors, that in Health kept the
Vessels turgid; Which Vessels I suppose to make up those Muscles. But when
the Pores are obstructed, that the nourishment is hindred (which then also
uses to be but sparingly administred) and sweats, either spontaneous, or
forced, are large, there must needs be a great expence of those Liquors,
the supply being but inconsiderable: which cannot but contract all these
ducts of all sorts nearer together, and make them much less in themselves,
meerly from Exhaustion: Or, if there should be no sweats, the internal Heat
spends the spirits, and dries up the Liquors; the consequence whereof may
reasonably be presumed to be this Flaccidity of parts, and great and sudden
Change, made in them; not that there is need of any _Parenchyma_ to fill up
these Muscles considering what hath been said. Mean while, I humbly
conceive, that if it be in any part of a Muscle, their Ingenuity, that
plead for it, will put them upon some experiments, to bring it to Ocular
Demonstration, either in Living or Dead Muscle, any kind of flesh, raw,
rosted, boyl'd, or in what they can best make it out. And when I shall be
convinc'd of an Errour in what I have discoursed, I shall beg pardon for
giving the Occasion of the trouble of that Experiment, which shall prove a
{320} _Parenchyma_ in any Muscle; and think my time well spent in receiving
a full satisfaction of the ungroundedness of my opinion; and readily submit
to the Author, with a grateful acknowledgement of my Obligation to any one
that shall rectifie me in my mistake, if it be one.

       *       *       *       *       *

_Observables touching _Petrification_._

Though much hath been already said and written of _Petrification_, yet 'tis
conceived, that all that comes so far short of a competent stock for the
composing of a perfect _History of Petrification_, that the incompleatness
thereof ought to awaken the more diligent attention of the Curious, and to
call in their aid for Additions, thereby so to encrease and to complete the
_Materials_ for that work, that it may the better serve to clear and make
out the Cause of that Transmutation. And that the rather, because if it lay
in the power of humane Skill (by the knowledge of _Nature_'s works) to
raise _Petrification_, or to allay, or prevent it, or to order and direct
it (which perchance in time might be attained the said way) much use might
be made of this Art; especially if it could be made applicable to hinder
the Generation of the Stone and Gravel in humane Bodies, or to dissolve the
Stone, where 'tis formed; besides other valuable Uses, that might be
excogitated.

Upon this Consideration, care is, and further _will be_ taken in these
Papers, to record, among other Observables of Nature, what shall be
communicated of this kind of _Change_.

In _Num._ 1. 2. and 5. several Relations have been made belonging to this
Argument. Much of it, together with considerable Reflections may be seen in
Mr. _Boyle_'s _Essay of Firmness_: In _Helmont de Lithiase_, where, among
other remarques, is recited the Testimony of _Paræus_ of a _Petrified
Child_ seen at _Paris_, and by the Owner used for a _Whetstone_: In
_Densingius_'s Historia _Infantis in Abdomine inventi, & in duritiem
lapideam conversi_: In Mr. _Hook_'s _Micrography_, and in others. To omit
now, what has been related (but perhaps not well enough attested) by
Authors, concerning the stupendious Petrifications of whole Companies of
Men, and Troops of Cattle; by _Aventinus_, lib. 7. _Annal. Bojorum_; by
_Purchas_ in his _Pilgrimage_ p. 416. in fol. printed at _London_ 1614,
and, (of a Troop of _Spanish_ Horsemen) by _Jos. Acosta_ lib. 3. c. 9.

To all which, the curious Dr. _Beale_ now adds a Narrative of a Stone, not
long since taken out of the Womb of a Woman of his neighbourhood neer
_Trent_ in _Somersetshire_, by incision, and afterwards perfectly cured,
though she had born the Stone with extreme torments for. 8. or 9. years.
The operation he relates to have been made in _Easter_ last; after which
time, he affirms to have seen the Stone, and weigh'd it in Gold Scales,
where it wanted somewhat of four Ounces, but had lost of the weight, it
formerly had, {321} being very light for a Stone of that Bulk. He further
describes to be of a whitish colour, lighter than Ash-colour; perchance
(_saith he_) not unlike to that recited out of _Scaliger_ by Mr. _Boyle_ in
his _Essay of Firmness_ pag. 238. _qui aëris contactis postea in gypseam
tum speciem tum firmitatem concreverat_. It had no deep asperities, and had
somewhat of an Oval figure, but less at one end, than a Hen-Egge, and
bigger and blunter at the other end, than a Goose egge.

This Stone, (so he concludes) is intended for the _Royal Society_, with the
Testimony of the _Chirurgion_, that perform'd the Operation, and other
Witnesses of special credit; where also will be annexed the _manner_ of
Operation.

It appears by this last clause (to add that on this occasion) that this
Well-wisher to the Improvement of all usefull knowledge, has taken notice
of that considerable _Collection of Curiosities_, lately presented to the
lately nam'd Society for their _Repository_, by the Publick-minded
Gentleman Mr. _Daniel Colwall_, a very worthy and useful Member of that
Body: To which Repository whatsoever is presented as rare and curious, will
be with great care, together with the _Donors names_ and their
_Beneficence_ recorded, and the things preserved for After-ages, (probably
much better and safer, than in their own private Cabinets;) and in progress
of Time will be employed for considerable Philosophical and Usefull
purposes; of which perhaps more largely in another place.

       *       *       *       *       *

_A Relation of a kind of _Worms_ that eat out Stones._

    This is taken out of a Letter, written by one _M. de la Voye_ to _M.
    Auzout_, to be found in the 32. _Journal des Scavans_; as follows.

In a great and very ancient Wall of Free-Stone in the _Benedictins Abby_ at
_Caen_ in _Normandy_, facing Southward, there are to be found many Stones
so eaten by Worms, that one may run his hand into most of the Cavities
which are variously fashion'd, like the Stones, which I have seen wrought
with so much Art in the _Louvre_: In these cavities there is abundance of
live-Worms, their excrement, and of that Stone-dust, they eat. Between many
of the Cavities there remain but leaves, as it were, of Stone, very thin,
which part them. I have taken some of these living Worms, which I found in
the eaten Stone, and put them into a Box with several bits of the Stone;
leaving them there together for the space of eight days; and then opening
the Box, the Stone seem'd to me eaten so sensibly, that I could no longer
doubt of it, I send you the Box and the Stones in it, together with the
living Worms: and to satisfie your Curiosity, I shall relate to you, what I
have observed of them both _with_ and _without_ a _Microscope_. {322}

These Worms are inclosed in a Shell, which is grayish and of the bigness of
a Barly-corn, sharper at one end, than the other. By the means of an
excellent _Microscope_ I have observ'd, that 'tis all overspread with
little Stones and little greenish Eggs; and that there is at the sharpest
end a little hole by which these Creatures cast out their excrement, and at
the other end, a somewhat bigger hole, through which they put out their
heads and fasten themselves to the Stones, they gnaw. They are not so shut
up, but that sometimes they come out, and walk abroad. They are all black,
about two _Lines_ of an inch long and three quarters of a _Line_ large.
Their Body is distinguish't into several plyes, and near their head they
have three feet on each side, which have but two Joynts resembling those of
a Lowse. When they move, their Body is commonly upwards, with their mouth
against the Stone. They have a big head, somewhat flat, and even, of the
colour of a Tortoise-Shell, braunish, with some small white hair. Their
mouth is also big; where may be seen four kinds of Jaw-bones, lying
crossewise, which they move continually, opening and shutting them like a
pair of _Compasses_, with four branches. The Jaws on both sides of the
mouth are all black, the nether Jaw hath a point like the Sting of a Bee,
but uniform. They draw threds out of their mouth with their fore-feet,
using that point to range them, and to form their Shells of them. They have
Ten Eyes, very black and round, which appear to be bigger than a Pins head.
There are five of them on each side of the head, standing after this
manner,

[Illustration]

But besides these Worms, I have found, that _Mortar_ is eaten by an
infinite number of small Creatures, of the bigness of Chees-Mites. These
have but two Eyes, and are blackish. They have four feet on each side
pretty long. The point of their Muzzle is very sharp, as that of a Spider.
I send you but one of them, though I had abundance, but they are dead and
lost. It may be, you'l find some at _Paris_, seeing that in the old Mortar
betwixt Stones, that is found in Walls made with rubbish, there is great
store of them, together with great plenty of their little Eggs. I have not
yet examined, whether these be those, that in the surfaces of all the
Stones, where they are met with, make little round holes, and small traces
and impressions, which make them look like _Worm-eaten Wood_. But 'tis
probable, they are such. It should be observed, whether these Worms do not
take Wings, and all the other appearances of Caterpillars; and whether they
are not to be found in plaister that is full of holes, in Bricks, in Greety
Stones, and in Rocks.

You may observe more of them in Walls exposed to the _South_, than in
others; and that the Worms, that eat the Stone, live longer, then those,
{323} that eat the Mortar, which keep not above eight days alive. I have
observed all their parts with a very good _Microscope_, without which, and
a great deal of attention, 'tis difficult to see them well.

I have seen other very old Walls altogether eaten, as those of the _Temple_
at _Paris_, where I could find no Worms, but the Cavities were full of
Shells of various kinds, diversly figur'd and turn'd: all which I believe
to be little Animals petrified.

       *       *       *       *       *

_Some promiscuous Observations, made in _Somerset shire_, and imparted by
the above-mentioned Dr. _Beale_._

His words are these, in a Letter to the _Publisher_, of the 24. _Septemb._
1666 at _Yeovill_ in _Somersetshire_;

I have two or three remarks, perhaps not unworthy to be recorded for
further application in like cases of time and place

1. In the Moores from hence towards _Bridgewater_, in the extreme drought,
we have endured this Summer, some lengths of pasture grew much sooner
whithered and parched, than the other pasture. And this Parched part seem'd
to bear the length and shape (in gross) of Trees. They digg'd, and found,
in the place, _Oakes_ indeed, as black as Ebony. And hence they have been
instructed to find and take up many hundreds of Oakes, as a neighbour of
good credit assures me. This advertisement may be instructive for other
parts, as _Kent_, _Essex_, _Lincoln_, &c.

[Sidenote: * _This had somewhat of a Vitriolate taste. But the Experiment
being made with greater quantities of this water, which questionless will
be done, the nature and kind of it may be better known._]

2. My Cosen _Philips_ of _Montague_ has in his pastures of _Socke_, about
three miles off, a large Pool, to which Pigeons resort; but the Cattle will
not drink of it, no not in the extream want of water in this drought. To
the taste it is not only brackish, but hath other loathsome tasts. In a
Venice-glass it looked greenish and clear, just like the most greenish
Cider as soon as it is perfectly clarified. I boyl'd a Pint of it in a
Posnet of Bell-Mettall (commonly used to preserve Sweatmeats:) suddenly it
yeilded a thick froth, whence I scumm'd half a score Spoonfulls; of which
the inclosed is a part, * Suffering the water to be boyl'd all away, it
left much of the same on the sides and bottom of the Posnet.

3. From _Lamport_, towards _Bridge water_, Eeles are so cheap in the frosts
of Winter, that they vend them for little. Their abundance is from hence,
that as the people walk, in the frosty Mornings, on the banks of river,
they discern, towards the edges of the banks, some parts _not hoar_, as the
rest, but _green_; where searching the holes of the banks they find heaps
of Eeles.

{324}

       *       *       *       *       *

_A Problem for finding the Year of the _Julian Period_ by a new and very
easie Method._

This occurs in the _Journal des Scavans_ n^o. 96. as it had been proposed
communicated to the Learned _Jesuit DE BILLY_. viz.

Multiply the _Solar_ Cycle by 4845. and the _Lunar_, by 4200. and that of
the _Indiction_, by 6916. Then divide the Sum of the Products by 7980.
which is the _Julian Period_: The _Remainder_ of the Division, without
having regard to the _Quotient_, shall be the year required after.

E. g. Let the Cycle of the _Sun_ be 3; of the _Moon_ 4; and of the
_Indiction_, 5. Multiply 3. by 4845, and you have 14535; and 4. by 4200.
comes 16800; and 5. by 6916. comes 34580. The Sum of the products is 65915,
which being divided by 7980. gives 8. for the _Quotient_, and the number
2075. which remains, is the Year of the _Julian Period_.

Some learned Mathematicians of _Paris_, to whom the said _P. de Billy_, did
propose this _Problem_, have found the Demonstration thereof; as the same
_Journal_ intimates.

       *       *       *       *       *

_An Account of some Books, not long since published._

I. TENTAMINA PHYSICO-THEOLOGICA DE DEO, _Sive_ THEOLOGIA SCHOLASTICA, _ad
Normam Novæ & Reformatæ Philosophiæ concinnata, & duobus libris
comprehensa. Quorum altero, de Dei existentia adversus Atheos & Epicureos
ex ipsorummet Principiis disputatur; altero, de ejusdem Essentia &
Attributis; primò secundum Theologiam Ethnicam, ubi explicatur, Quantum
hactenus Alii in Gentilium sententiis, de summi Numinis Natura eruendis,
hallucinati fuerint; deinde secundum Theologiam Christianam: Et quid de
Divina Essentia ac Attributis statuendum sit, diceretur. Quibus postremò
accedit specialis Dissertatio de Primo Numinis Attributo, ÆTERNITATE_.
Authore _Samule Parkero_, A. M.

This Treatise, published the last year, would sooner have been taken notice
of in these _Tracts_, had it not escaped the _Publishers_ view till of
late, when he, upon serious perusal, found it very worthy the recommending
it to all sorts of persons; and particularly to those who either please
themselves with that fond opinion, _That Philosophy is the Apprentiship of
Atheisme_; or hearken to the aspersions, that are generally laid upon the
_Reformation_ of _Philosophy_.

This excellent piece removes both these; and being joyned and compared with
the truly Noble Mr. _Boyle_'s Considerations in his _First part_ of the
{325} _Usefulness of Experimental-Natural Philosophy_, will strongly
evince, How Much that Philosophy, which searches out the real Productions
of Nature (the true Works of God) does manifest the Divine Glory more, than
the Notionals of the Gentiles.

This Author (now a Fellow of the _Royal Society_) delivers his Matter in
two Books.

Lib. 1. Cap. 1. Atheists are disappointed of the Authority of _Epicurus_,
and of other Antient Philosophers, for their gross Atheisme.

Cap. 2. The beautiful Frame of the World evinceth the Architectonical
Author and Governor.

Cap. 3. The admirable Contrivance in the Structure of Mankind, and of
Animals, does more conspicuously shew the Deity.

Cap. 4. The Atheist caught in his own Net, or convinced by the true force
of his own Arguments.

Cap. 5. The Arguments devised against Atheists by _Des Cartes_, and drawn
from the _Idea's_ of our Mind, examin'd and found imperfect and invalid.

Lib. 2. Cap. 1. The opinions of the Gentiles concerning God, unduly applied
to the _Deity_, which we worship: but properly to be understood by them of
the _Sun_, or of the _Soul of the World_.

Cap. 2. More expresly proved, that the Antient Philosophers conceived, the
_Soul of the World_ to be God.

Cap. 3. The Historical Theology of the Gentiles for the most part is unduly
applyed or accommodated to the Holy Scriptures.

Cap. 4. The Divine Substance, Immensity, Incomprehensibility, Invisibility,
explicated, as far as our weak reason does teach.

Cap. 5. The Divine Perfections, and other Attributes and Affections, how
far explicable.

Cap. 6. The Eternity of God, how apprehended.

These are in short the Heads of the Book, which is yet but in Latin. It
were to be wisht, the Author would make it speak his own lively _English_.



II. HONORATI FABRI _Soc. Jesu Theologi, Tractatus duo; quorum Prior est de
Plantis & de Generatione Animalium; Posterior de Homine._

As the Matter of this Book is considerable, so is the order and dependence
of all its parts excellent; in regard that all the Propositions are ranged
according to a Geometrical method, and so well disposed, that the latter do
always suppose the former, and seem to depend all of them upon certain
evident principles, whence they flow by a natural consequence.

This _Volume_ contains two Treatises.

The _First_ is divided into 5. Books. In the _four first_, he treats of
_Plants_, and distributes them into three _Classes_; some growing _in the
Earth_, as _Trees_; others, growing upon _Plants_, as _Mosse_; and a third
sort growing upon _Animals_, as _Hair_, _Horns_, and _Feathers_. He examins
and considers the {326} Parts of all these Plants and their Use, the
manner, how they are produced, and nourished; and their different
Qualities. He discourses also of Bread, Wine, Oyle, and the other Mixtures,
that are made of Plants.

In the _Fifth Book_, he treats of the _Generation of Animals_, where he
delivers many curious matters, explicating in a very easie and familiar way
that Argument, which hath always been lookt upon, as one of the obscurest
in Natural Philosophy.

The _Second_ Treatise consists of 7. Books; wherein the Author considers,
what appertains to _Man_. He discourses _first_, of Digestion, of the
Circulation of the Bloud, and of the Use of the principal parts of the
Humane Body. _Next_, he treats of the Senses, External and Internal; of all
the Motions of the Body, both Natural and Voluntary, of the sensitive
Appetite, and the Passions; _Thence_ he proceeds to the Temperaments,
Habits, Instinct, Sleep, Sickness, &c. _Lastly_, passing to the _Rational
Soul_, he endeavours to demonstrate the Immortality thereof, and to explain
also the Manner, how it worketh upon the Body, and is united with the Body;
where he omits not to reason of all the Powers of the Soul, of Liberty, and
of the Operations of the Understanding and Will.

In _general_, the Author makes it his study, for the explicating of the
most perplext Difficulties, to shew, that Nature works not but by very
simple and easie wayes.

In _particular_ he intersperses several curious remarks. _E.g._ He teaches
how to make _Perspectives_, that magnifie Objects, without Glass; telling
us, that when an Object is look't upon through a small hole, it appears
much greater than it is; and that therefore, if instead of Glasses one did
cast before ones eyes two _Plates_ having little holes in them, it would
furnish us with a new kind of _Perspectives_, more commodious than those of
Glasses, which spoil the Sight by reason of the refraction of the Rayes,
caused thereby. _Again_, He renders the cause of that common, but
surprising, effect of Painters, drawing certain Pourtraictures, which seem
to look directly upon all their Beholders, on what side soever they place
themselves: _Videl._ That in those Pictures, the Nose it a little turned to
one side, and the eyes to the other. Whence it comes, that such pictures
seem to look to the right side, because the Eyes are indeed turned that
way; but they appear also to look to the left, because the point of the
Nose is turned that way, and the Table, whereon the Picture is drawn, being
flat the Looker on perceives not, that the Eyes are turned th'other way;
which he would do, if the Eyes of the Pourtrait were convex: Whence it
comes, that no Figure can be made embossed, which looks every way.

The art, which he teaches of making _Parsley_ shoot out of the ground in a
few hours, is this. Infuse the seed of it in Vinegar; and having sown it in
good ground cast on it a good quantity of the Ashes of Bean-Cods, and
sprinkle it with Spirit of Wine, and then cover it with some linnen. He
mentions also; that if you calcine Earth, and then water it well, it will
{327} produce a great variety of different Herbs, and that the Ashes of
Corn burnt, being sown, have sometimes produced other Corn.

To add that by the by, this Author is not so addicted to _Aristotle_, as to
be on his side, when he thinks Truth is not. He hath emancipated himself
considerably from the _Scholastick_ way of Philosophing. He dares maintain,
that the Vegetative and Sensitive Souls are not _Substantial_ Forms; and
that it is with Plants and Animals, as with Artificial things, the Form
whereof results from the Union and Disposition of the parts. According to
this _Hypothesis_ he explicates all the Operations of Plants and Animals,
without having any recourse to the Soul. He avers also, that there are no
_Species Intentionales_, and no Habitudes, and that the Animal Spirits,
which Philosophers commonly believe to be necessary for all the Operations
of Life, are useless.

It might also be observed out of this Author, what he discourses of the
Generation of Animals by Putrefaction; of the Cause of intermittent
_Feavers_, and of the Animal Instinct, and of many other particulars; were
it not better to refer the curious to the Book it self.



III. _RELATION DU VOYAGE de l' Evesque de Beryte, par la Turquie, la Perse,
les Indes, _&c._ jusques au Royaume de Siam, & autres lieux_; par M. _de
Bourges, Prestre_ &c.

This Author imploying his Pen chiefly, according to his design, to give an
Accompt of the Success, the Undertakers of this Voyage had, in propagating
the Christian Faith in the remoter parts of the World, and relating on that
occasion, What number of Churches they have founded in _Cochin_, _China_,
and the Kingdom of _Tonquin_, (in which latter alone he affirms, that there
are more than three hundred thousand Christians;) being I say principally
intent upon that Subject, he seems not to have made many Philosophical
observations in those places. Mean while he does good service to those that
have occasion to travel into the _East-Indies_ mostly by Land, by
describing the passage, they took thither; which was, That they embarqued
at _Marseilles_, in _September_, the most convenient and favourable season
for that Voyage; whence Ships do ordinarily pass every Month from _Syria_,
reckoning one Month for the time of Sayling, to _Alexandretta_. Thence to
_Aleppo_, counting one Month more for the Stay, to be made there to meet
the _Caravane_ for _Babylon_, and six weeks more for the march from
_Aleppo_ to _Babylon_, where a fortnight will pass before an opportunity
happen to embarque upon the _Tyger_ for _Balsora_; which Journey will
require a fortnight more: And about this time it will be about the end of
_January_. Thence is always conveniency to pass from _Congo_, 4 days
Journey from _Comoron_ or _Gombroun_, to which latter part there is also
frequent occasion to pass by Sea from _Balsora_, which will take up some 15
or 16. days Sail. There (vid. at _Comoron_) you will every year meet with
_English_, _Portugal_, _Dutch_, and _Moorish_ Vessels, from _Surat_, from
_October_ till the end of _April_, for they are obliged to be at _Surate_,
before the end of _May_, because all the ports of those {328} _Indies_ are
shut the 4. ensuing months, by reason of the danger of that _Sea_.

But besides this Direction, the Book is not quite destitute of _Natural_
Observations. It relates, 1. How Diamonds are found and separated in
_Golconda_; They take of the Earth, held to be proper to form them, which
is reddish, and distinguish'd with white veins, and full of flints and hard
lumps. Then they put near the places, which they will digge, a close and
even Earth; and to it they carry those Earths, they have digg'd out of the
Mine, and gently spread it abroad, and leave it exposed to the Sun for two
days. Then being dryed enough they beat it, and sifting this Earth, they
find the Diamonds in ashes of Flints, in which Nature hath set them. Here
he adds, that the King of that Country farms out these Diamond-Mines for
600000. Crowns _per annum_, reserving to himself the right of all the
Diamonds, that exceed ten _Carats_ in weight. There are Diamonds, that
mount to 35. and 40. _Carats_. And this is the great Treasure of that
Prince.

2. That the most esteemed fruit in those parts; the _Durion_ (of the
bigness and shape of an ordinary _Melon_) has a very unpleasing and uneven
untollerable smell, like to that of a rotten _Apple_.

3. That _Rice_ prospers most in waterish grounds; and that the fields,
where it grows best, resembles rather to Marshes, than to any ploughed
Soyle: Yea, that that Grain has the force, though 6. or 7. foot water stand
over it, to shoot its Stalk above it; and that the Stem, which bears it,
rises and grows proportionably to the height of the water, that drowns the
field.

4. That the way of keeping ones self harmless from a wild _Elephant_, when
he runs directly upon one, is, to hold something to him; as a Hat, a Coat,
a piece of Linnen, which he seises on with his Trunk; and playes with it,
as if he were pleased with this apparent homage, done to him; and so passes
on. If he be in a rage, that then the only remedy is, to turn incessantly
behind him to the left side, in regard that naturally (_saith this Author_)
he never turns himself that way, but to the right: And the time, there is
to turn, because of the Beasts unweildiness, affords leisure enough to
climbe up some high Tree, or to mount some steep ground: all which if it
fail, by holding always his tail, and turning with him, the Animal will be
tired, and give opportunity to escape.

       *       *       *       *       *


_London_, Printed by _T. R._ for _John Martin_, Printer to the _Royal
Society_, and are to be sold at the _Bell_ a little without _Temple-Bar_.

{329}

       *       *       *       *       *




_Numb._ 19.

PHILOSOPHICAL
_TRANSACTIONS._

       *       *       *       *       *

_Munday_, _November_ 19. 1666.

       *       *       *       *       *

The Contents.

    _An Addition to the Instances of _Petrification_, formerly enumerated.
    Articles of _Inquiries_ concerning _Mines_; as, to the neighbouring
    Country about them; the Soyl where they are; the Signes of them; the
    Structure and other particulars belonging to the Mines themselves; the
    Nature and Circumstances of _Ore_; and the Reduction of _Ore_ into
    _Metal_. Promiscuous _Inquiries_ formerly recommended to Monsieur
    _Heuelius_, particularly about _Cold_; together with his own, and his
    Correspondents _Answer_ to some of them. The success of the Experiment
    of Transfusing the Blood of one Animal into another._

       *       *       *       *       *

_An Addition to the _Instances_ of _Petrification_, enumerated in the last
of these _Papers_._

    _This _Instance_ was some while since communicated to the _Royal
    Society_ by that Ingenious Gentleman Mr. _Philip Packer_, a worthy
    Member of that Body; in these words;_

On a Bank in a Close of Mr. _Purefoy_, neer his house, call'd _Wadley_, a
mile from _Farrington_ in _Berks_, there grows an _Elme_, which hath now
lost the top, and is grown hollow, containing neer a Tun of Timber. From
the But of the same Tree, one of the spreading Clawes having been formerly
cut off with an Axe, that part of the But, from whence the same was
sever'd, being about 1½ foot above ground, and inward within the trunk
{330} of the Tree, hath contracted a petrfied Crust, about the thickness of
a _shilling_, all over the woody part within the Bark; the Marks of the Axe
also remaining very conspicuous, with this petrified crust upon it. By what
means it should thus happen, cannot well be conceived, in regard there is
no water neer it; the part, above the ground and out of the weather; the
Tree yet growing: unless being cut at some season, when the sap was
flowing, the owsing of the sap might become petrified by the Air, and the
Tree grow rotten and hollow inward since that time; which how long since,
is not known.

A piece of that part cut, was presented, together with this Account, to the
said _Society_, for their _Repository_.

       *       *       *       *       *

_Articles of Inquiries touching _Mines_._

What the Honourable _Robert Boyle_ gave the Reader cause to hope for, in
_Numb_. 11. when he was pleased to impart those _General Heads_ for a
Natural History of a Country, _there_ publish'd; He is not un-mindful to
perform, by enlarging them as occasion serves, with _Particular_ and
_Subordinate_ Inquiries. Here he gratifies the Curious with a considerable
Set of Inquiries about _Mines_: which though unfinish'd, yet the
_Publisher_, was instant to obtain their present Publication, to the end,
that he might the more conveniently recommend them to several Forreigners
of his Acquaintance, now ready to return to their several Countryes, which
he understands to abound in Mines; and from the Curious Inhabitants
whereof, he expects to receive a good Accompt upon some at least of these
Inquiries; which also by several of them have been earnestly desired, as
Instructions, to direct them, what Particulars to inquire after upon this
Subject.

These Quæries are reduced by the _Author_ to six Heads:

The _first_, The neighbouring Country about the Mines.

The _second_, The Soyl where the Mines are.

The _third_, The Signs of Mines.

The _fourth_, The Structure and other particulars belonging to the Mines
themselves.

The _fifth_, The Nature and Circumstances of the Ore.

The _sixth_, the Reduction of the Ore into Metal. {331}

_QUÆRIES_

_About the first Title._

1. Whether the Country be Mountainous, Plain, or distinguish'd with Vales?
And in case it be mountainous, what kind of Hills they are; whether high,
or low, or indifferently elevated? Whether almost equal or very un-equal in
height? Whether fruitful or barren; cold or temperate; rocky or not; hollow
or solid? Whether they run in ridges, or seem confusedly placed; and, if
the former, what way the ridges run, North and South, &c. And whether they
run any thing parallel to one another?

2. Whether the Country be barren or fruitful? And, if any way fruitful,
what it produces, and what it most abounds with?

3. What Cattle it nourishes, and whether they have any such thing peculiar
in point of bigness, colour, shape, longævity, fitness or unfitness to make
good meat, &c. as may be rather adscribed to the peculiar nature of the
place, than to the barrenness of the Soyl, or other manifest causes?

4. Whether the Natives, and other Inhabitants, live longer or shorter than
ordinary? Whether they live more or less healthy? Whether they be subject
to any _Epidemical_ Diseases, that may very probably be imputed to the
Mines; and what these Diseases are; and what Remedies are found successful?

5. Whether the Country be, or be not furnish'd with Rivers, Brooks,
Springs, and other Waters; and how these waters are conditioned?

6. Whether the Air be dry or moist; hot or cold; clear or foggy; thick or
thin; heavy or light; and especially, whether the Weather be more or less
variable than ordinarily; or whether it be subject to great and sudden
changes, that may probably be imputed to the Mineral and Subterraneous
Steams; and what they are? {332}

_About the second Title._

7. Whether the _Soyle_ that is neer the Surface of the Earth, be Stony;
and, if it be, what kind of Stones it abounds with? Whether it be Clayie,
Marley, Chalkye, &c. And, if it be of several kinds, how many they are; and
by what properties they are distinguish'd?

_About the third Title._

8. By what _Signs_ they know or guess, that there is a Mine in such a
place?

9. These Signs are _either_ upon the Surface of the Earth, _or beneath_ it.

To the _former_ belong these _Quæries_.

10. Whether the Ground be made barren by Metalline or Mineral Effluviums?

11. Whether it be observed, that Trees and other greater Plants seem to
have their tops burnt, or other leaves or outsides discoloured? or whether
there be any Plants, that do affect to grow over such Mines; and whether it
have been tryed, that other Plants, that would prosper in the adjacent
places, will not be made to grow and thrive there?

12. Whether the Stones and Pebles, that are wash'd by the Brooks, Springs,
or other Waters, have any colour'd substance left upon them; and if they
have, of what colour, weight, &c. these adherences are?

13. Whether the Waters of the place proposed, do by their tast, smell,
ponderousness, &c. disclose themselves to contain Minerals? And, if they
do, what Minerals they or their residences, when they are evapourated away,
do appear to abound with, or to participate of?

14. Whether _Snow_ will not lye, or _Frost_ continue so long, or _Dew_ be
generated or stay upon the ground in the place proposed, as on other
neighbouring grounds?

15. Whether the _Dew_ that falls on that ground, will discolour white
Linnen or Woollen-Cloths, spred overnight on the {333} surface of the
ground, and employed to collect the Dew? And whether the _Rain_ that falls
there, and may be supposed to come thither from elsewhere, will discolour
such Clothes, or afford any residence of a Mineral Nature?

16. Whether the Place be more than ordinarily subject to Thunder and
Lightning, and to sudden Storms or Earthquakes; as likewise to Nocturnal
Lights and fiery Meteors.

17. Whether Mists use to rise from Grounds stored with Minerals? What is
observable in them, and what Minerals they signify, and may be supposed to
be produced by?

18. Whether the _Virgula Divinatoria_ be used to find out the Veins of
proposed Mines; and, if it be, with what success?

19. What other Signs above ground afford probability of Mines, or Direction
for following a Vein over Hills, Valleys, Lakes, Rivers, &c.

The _second_ sort of _Signs_ belonging to these _Quæries_, are such as
follow.

20. Whether there be any Clayes, Marles, or other Mineral Earths, yellow or
liquid matters, that usually give notice of the Ore? And if there be more
than one, how and at what depths they are wont to lye respectively? Of what
thickness and consistence they are; and in what Order the Diggers meet with
them?

21. Whether there be any Stones or _Marchasites_ to be found neer, or not
very far from the surface of the ground, by which one may have ground to
expect a Mine? As is often observed in the Tin-Mines of _Cornwall_, over
which such kind of Stones are divers times found lying above ground?

22. Whether all Stones of that kind do equally signify that Mine? And, if
not, how the significant Stones are to be known, as by Colour, Bigness,
Shape, Weight, Depth under ground, &c.

23. Whether there be any Earths of peculiar kinds, as to Colour,
Consistence, &c. that indicate a Mine beneath or near them; and, if there
be, what they are, and what is their consecution, if they have any?

24. Whether Heat or Damps give any assurance or a probability of finding a
Mine? {334}

25. Whether Water of any kind, met with in Digging, especially at this or
that depth, do betoken a Mine?

26. Whether there be any Signs of the neerness of the Mine, and what they
are?

27. Whether there be any Signs of ones having miss'd the Mine, either by
being past above, or beneath, or having left it on either hand; and what
they are?

28. Whether there be any Signs not only of the distinct and determinate
kind of Metals or Minerals; but of the Plenty and Goodness of the Vein; and
what they are?

29. Whether there be any Signs of the depth of the Vein beneath the surface
of the Earth; and what they are?

30. Whether there be any proper or peculiar Signs, that show it to be
hopeless, or at least unlikely, to find a Vein in the place where it is
digg'd for; and what those are?

_About the fourth Title._

31. What is the depth of the Shaft or Groove (which though named in the
_singular_ Number; the Questions about it are _generally_ applicable) till
you come at the Vein or Ore?

32. Whether the Vein run or lye Horizontal, or dippe? And if it dippe, what
_inclination_ it hath, how deep the lowest part lies; and consequently how
much deeper than the uppermost? As also, what it's Flexures, if it have
any, are? And whether it runs directly _North_ or _South_, _East_ or
_West_; or seem rather to have a Casual tendency, than any determinate one
by Nature? and how far it reaches in all?

33. What is the Wideness of the Groove at the Top, and elsewhere? Whether
the Groove be perpendicular or crooked; and if crooked, after what manner,
and with what distance it winds?

34. How the Groove is supported? What are the kinds, length, bigness, and
way of placing the Timber, Poles, &c. that are employed to support it? And
how long the Wood will last, without being spoyled with the subterraneous
fumes and waters? and what wood lasts longest? {335}

35. What Air-shaft belongs to the Mine? Whether it be _single_, or more
than One? Of what breadth the Air-shaft is at the Orifice? Whether it be
convenient enough, or not? How neer it is placed to the Groove; and in what
position? And if there be _several_ Air-shafts, what their Distances and
scituation are in reference to the Groove, and to each other? Or how Air is
supplied, if there be no Air-shafts?

36. Whether they meet with any Waters in the Mine? And, if they do, how
copious they are; at what depths they occur; how they are qualified; and
what way they Spring, &c.

37. Whether they are constant or temporary? whether they increase or
diminish notably in Summer or Winter, or at any other time of the year; and
if they do, at what season that is; how long it is wont to last; and the
proportions of Increase and Decrease?

38. What Expedients and Engines are employed to free the Mines from Water?
The materials, the parts, the bigness, the shapes, the coaptation; and, in
short, the whole structure, number, and way of applying the Instruments,
that are made use off to free the Mines from Water?

39. What are the Conditions, Number, &c. of the _Adits_?

40. Whether the Mine be troubled with _Damps_, and of what kind they are?
whether they come often or seldom at any set time, or altogether
irregularly? what Signs fore-run them? what mischief they do? what remedies
are the most successfully imployed against them, aswell in reference to the
Cleering of the Mine, as to the Preservation and Recovery of the Workmen?

41. What Methods the Mine-men use in following the Vein, and tracing their
passages under ground (which they call _Plumming_ and _Dyalling_) according
to the several exigencies? And whether they employ the Instruments, made
with the help of the Load-stone, the same way that is usual; and if not,
wherein they differ in the use of the same Instruments; or what Instruments
they substitute in their place?

42. What ways they take to secure themselves from the uncertainty, incident
to the guidance of _Magnetick_ Needles from the _Iron-Stone_ or Ore, that
they may meet with under ground? {336} (of which yet perhaps there is not
so great danger, as one may imagine; as far as I could find by a Trial, I
purposely made in a Groove, where I was sure, there wanted not Iron-Ore.)
And what other wayes may be used to direct Miners without the help of a
Load-stone?

43. How the Miners deal with the Rocks and Sparrs, they often meet with,
before they come at the Ore? Whether they use Fire to soften, calcine, or
crack them? How they employ it, and with what measure of success?

44. What wayes and cautions they use, to free the Mine and secure the
Work-men from the inconveniencies and danger accruing from the use of much
fire in it?

45. What Instruments they use to break the Rock &c? And how those
Instruments are conducive; and how long they last?

46. How the Mine-men work; whether naked or cloathed? And what Lights they
use to work by; what materials they are made of, what measure of light they
give; how long they last; and by what wayes they are kept burning in that
thick and foggy air?

47. How Veins are follow'd, lost, and recover'd? And how several Miners
work on the same Vein? And what is the best way of getting all the Ore in a
Vein, and most conveniently?

48. How they convey out their Ore, and other things, that are to be carried
out of the Mine? Whether they do it in Baskets drawn up by Ropes, or upon
Mens backs; and if this last-named way; what kind of Vessels they use for
matter, shape, and capacity? And whether the Work-men deliver them one to
another; or the same Work-men carry them all the way? And whether the
Diggers descend and ascend by Ladders of Wood, or of Ropes, &c.

_About the Fifth Title._

49. Whether the Ore runs in a Vein; or lie dispers'd in scatter'd pieces;
or be divided partly into a Vein, and partly into loose masses; or like a
Wall between two Rocks, as it were in a Cleft; or be interspers'd in the
firm Rock, like speckled Marble? Or be found in _Grains_ like _Sand_ or
_Gravel_; as store {337} of excellent _Tin_ is said to be found in some
parts of _Cornwall_ at the Sides and in the Channels of running Waters,
which they call ...; or whether the Ore be of a softer consistence, like
_Earth_ or _Lome_, as there is Lead-ore in _Ireland_ holding store of
Silver, and Iron-ore in the North parts of _Scotland_ and elsewhere? And
what is observable in it as to Weight, Colour, Mixture, &c?

50. Whether any part of the Metal be found in the Mine perfect and
complete? (As I have had presented me good valuable _Copper_, and pieces of
perfect _Lead_, that were taken up, the one at _Jamaica_, and the other by
an acquaintance of mine, that took them out of the ground himself in _New
England_.)

51. Whether the Mine affords any parcels of Metal, that seem to grow like
_Plants_ (as I have sometimes seen Silver growing, as it seemed, out of
Stone, or _Sparre_ almost like blades of Grass; as also great Grains of a
Metal, which appear'd to me, and which those, that tryed some of it,
affirmed to be Gold, abounding in a stony lump, that seem'd to consist
chiefly of a peculiar kind of _Sparre_.)

52. Whether the Vein lie near, or much beneath the surface of the Earth,
and at what depth?

53. Whether the Vein have or have not any particular Concomitants, or Coats
(if I may so call them;) and, if any, what they are, and in what order they
lie? (As the Veins of _Lead-ore_, with us, have frequently annnext to them
a Substance call'd _Sparre_, and next to that another, call'd _Caulk_.)

54. Whether (besides these Coats) the Vein have belonging to it any other
_Heterogeneous_ substance? (As in _Tin-mines_ we often find that yellow
substance, which they call _Mundick_.)

55. What are the principal Qualities of these Extraneous substances? (As
that _Sparre _ is white, but transparent, almost like course Crystall,
heavy, britle, easily divisible into flakes, &c. _Caulk_ is of a different
texture, white, opacous, and like a Stone, but much more ponderous.
_Mundick_ I have had of a fine golden colour; but, though it be affirm'd to
hold no Metal; yet I found it in weight, and otherwise, to differ from
_Marchasites_; and the Mine-men think it of a poisonous nature.) {338}

56. Whether the Vein be inclosed every way in its Coats; or whether it only
lye between them?

57. Whether the Vein be every way of an uniform breadth, and thickness;
and, if it be, what these Dimensions are; and if not, in what places it
varies, and in what measures? (The like Questions are to be made concerning
the _sparre_, _Caulk_, and other Teguments or mixtures of the Ore?)

58. Whether the Vein be un-interrupted, or in some places broken off; and
whether it be abruptly, or not; and whether it be by Vales, Brooks,
Gullets, &c?

59. How wide the Interruptions are? what Signs, whereby to find the Vein
again? whether the ulteriour part or division of the Vein be of the same
Nature, and hold on in the same Course, as to its tendency upwards or
downwards, or Horizontally, Norward, Southward, &c. with the Vein, from
which it is cut off?

60. Whether, in case the last end of the Vein be found, it terminate
abruptly, or else end in some peculiar kind of Rock or Earth, which does,
as it were, close or Seal it up, without leaving any crack or cranny, or
otherwise? And whether the terminating part of the Vein tend upwards,
downwards, or neither? And whether in the places, where the Vein is
interrupted, there be any peculiar Stone or Earth, that does, as it were,
seal up the Extremity of it?

61. Whether it be observed; that the Ore in Tract of time may be brought to
afford any Silver or Gold, which it doth not afford, or more than it would
afford, if it were not so ripe? And whether it have been found, that the
Metalline part of the Vein grows so, that some part of the Mine will afford
Ore or Metal in tract of time, that did not so before? And whether to this
Maturation of the Mine, the being exposed to the free Air be necessary; or,
whether at least it conduce to the Acceleration of it; or otherwise?

62. Whether all the Ore, contained in the Mine, be of the self-same nature
and goodness; and, if not, what are the differing kinds; and how to be
discriminated and estimated?

63. What is the fineness and goodness of the Ore, by which the Mine is wont
to be estimated? And what are the marks and {339} characters, that
distinguish one sort from another?

64. What proportion of Metal it affords? (As in our _Iron-mines_ 'tis
observed, that about three Tuns of Iron-stone will afford one Tun of Metal:
And I have had _Lead-Ore_, which an Ingenious man, to whom I recommended
such Tryals, affirm'd to me to afford three parts in four of good Lead.)

65. Whether the Ore be pure in its kind from other Metals, and, if not, of
what Metals it participates; and in what proportion? Which is especially to
be Inquired into, in case the Mine be of a _base_ metal, that holds a
_noble_ metal: (As I have known it observ'd, that _Lead-Ore_, that is poor
in its own metal; affords more Silver, than other; and I remember, that the
_Ore_ lately mention'd, being rich in Lead, scarce afforded us upon the
_Cuppel_, an Atome of Silver. And _Matthesius_ informs us, that a little
Gold is not unfrequently found in _Iron-Ore_. And I have by me some Gold,
that never endur'd the Fire, taken out of a Lump of Tin-Ore.)

_About the sixth Title._

66. What are the mechanick and prævious Operations, as Beating, Grinding,
Washing, &c. that are used to separate the Ore from the Heterogeneous
Bodies, and prepare it for the Fire? Or whether the Ore requires no such
preparation? (as it often happens in Lead, and sometimes in Iron, &c.)

67. Whether _Mercury_ be made use off, to extract the nobler from the baser
metals? (as is their practice in _Peru_, and other parts of the
_West-Indies_.)

68. Whether the leaving the Ore expos'd to the open Air and Rain for a good
while, be used as a Præparative? (as I have seen done in _Iron-stone_.)

69. Whether the Burning and Beating of the Ore be used to prepare it for
the Furnace? (as is practised in _Iron_, and almost always in _Copper_:)
And, in case they use it more than once, how often they do it; (for,
_Copper-Ore_ is in some places washed 8. or 10. times, and in others, 12.
or 14.) and with what circumstances; as, how long the Ignition lasts at a
time, whether the Ore be suffer'd to cool of it self, or be quench'd?
whether it be washed betwixt each Ignition?

70. What Flux-powders, and other ways they have to try {340} and examine
the goodness of the Ore in small quantities?

71. Whether, when they work in _great_, they use to melt the Ore with any
Flux or Additaments, or only by the force of the Fire, or in any way
between both? (As throwing in of Charcoals when they melt Iron-stone does
not only serve to feed the Fire, but perhaps by the _Alchaly_ of its Ashes
to promote the fusior: so Lime-stone, &c.)

72. What kind of Furnaces they use, to melt the Ore in? Whether they be all
of one sort and bigness, or of differing?

73. What are, the Situation, Materials, Dimensions, Shape, Bigness, and in
short what is the whole structure and Contrivance of the Furnace? If there
be any thing peculiar and remarkable? What Tools are used in Smelting,
their Figures, use, &c. And the whole manner of working?

74. What kinds of Fewel, and what quantities of it, are wont to be employed
in the Furnace, within the compass of a day, or week? How much is put in at
a time? How often it is renewed? And how much Ore in a determinate time, as
a week or a day, is wont to be reduced to Metal?

75. In case an Additament be employed, what that is, and in what proportion
it is added? Whether it be mingled with the Ore, before that be put into
the Fire, or cast in afterwards; and, if so, at what time, &c?

78. Whether the Ore be melted by a Wind, excited by the Fire it self; as in
Wind-ovens? Ore by the course of Waters? Or acuated by the blast of
Bellows; and, if so, whether these Bellows be mov'd by a Wheel, turn'd by
Water running under it, or falling on it? And what are, the Dimensions,
Situation, &c. of the Bellows?

79. What contrivance they have, to let or take out the Metal, that is in
fusion; and cast it into Barrs, Sows, Pigs, &c?

80. What Clay, Sand, or Mould they let it run or pour it through? And after
what manner they refrigerate it?

8l. Whether or no they do, either to facilitate the fusion, or to obtain
the more or better Metal, mingle differing sorts or degrees of Ore of the
same metal? (As in some places 'tis usual, to mingle poor and rich Ore; and
at _Mendip_ they mix two or more of these differing kinds of _Lead-ore_
that they call _Frim-ore_, _Steel-ore_, _Potern-ore_, &c.) {341}

82. Whether or no, having once brought the Ore to fusion, they melt all the
Metal it self, to have it the more pure? And, if they do, with what
circumstances they make the fusion?

83. Whether they have any Signs, whereby to know whether the Fusion have
been well or ill perform'd; and the Metal have obtain'd the perfection, to
be expected from such Ore, melted in such a Furnace?

84. Whether they observe any great difference in the goodness of the Metal,
that first melts, from that of the rest of the Metal which comes afterwards
in the same or another operation? And whether the Rule holds constantly?
(For, though they observe in _Tin-Mines_, the best Metal comes first, yet
in the works of an Industrious friend of mine, he informs me, that the best
Metal comes last.)

85. Whether the produced Metal be all of the same goodness? And if it be,
how good it is in reference to the Metal of other Mines, or other parts of
the same Mine or Vein? And if it be not, what differences are observ'd
between the produced portions of Metal; and what disparity that amounts to
in the price?

86. What are the Wayes of distinguishing them, and estimating their
goodness?

87. Whether they do any thing to the Metal, after it is once brought to
Fusion, and, if need be, melt it over again, to give it a melioration? (As
when _Iron_ is refined, and turn'd into Steel;) And what distinct Furnaces,
and peculiar Ways of ordering the Metals are employ'd to effect this
improvement? With a full description of them and the Tools in all
Circumstances, observ'd in the refining of Metals.

88. Whether in those places, where the Metal is melted, there be not
elevated some Corpuscles, that stick to the upper parts of the Furnace, or
Building? And, if there be, whether they be barely fuliginous and
recrementitious exhalations, or, at least in part, Metallin Flowers? (As in
the _Cornish_ Tin-mines, after some years they usually destroy the thatch'd
Houses, where the Ore hath been melted, to get the stuff, that adhears to
the insides of the Roofs, out of which they melt store of excellent Tin.)

89. Whether the Metal, being brought to fusion, affords {342} any
Recrements? (As _Iron-stone_ affords store of a dark Glass or Slagg) And,
if it do, what those Recrements are? How they are separated from the Metal;
and to what Uses they are employed?

90. Whether, after the Metal has been once melted, the remaining part of
the Ore being exposed to the Air, will in tract of time be impregnated, or
ripen'd, so as to afford more Metal? (For, this is affirm'd to me of the
_Cornish_ Tin-Ore; and what remained after the fusion of _Iron-ore_ in the
_Forest of Dean_, is so rich in Metal, that a Tenant of mine in _Ireland_,
though he had on the Land, he held from me, an Iron-Mine, found it less
profit to work it, than to send cross the Sea to the _Forest of Dean_ for
this already us'd Ore, which having lain for some ages, since it was thrown
aside in great heaps expos'd to the Air, he affirm'd to yield as well great
great store of Iron, as very good: though I somewhat doubt, whether this be
_totally_ to be ascribed to the Aire, and length of time; or to the leaving
of Metal in the Slaggs in old times, before great Furnaces were in use.)

       *       *       *       *       *

_Promiscuous Inquiries about Mines, from the same Author._

1. Whether the Territorie, that bears the Mine, abounds with no other Kind
of Mineral in some distinct part of it? (As in _Kent_ near _Tunbridge_, one
part of the Country which is Hilly, abounds all along with _Iron-Mines_;
the other, which is also Hilly, and divided from it but by a small Valley,
abounds exceedingly (as the Diggers and Inhabitants told me upon the place)
in _Quarry's_, which the Metallin-Country wants, but is quite destitute of
Iron-stone. And so at _Mendip_, in one part of the Hill, I saw store of
_Lead-Mines_, containing several Kinds of Ore of that Metal; another part
of the Hill I found to be full of _Cole-pits_, which had some
_Marchasites_, but no Metal; and in another place, _Iron-ore_, and mixt
Ores, which yet they did not think fit to work.)

2. Whether the Air appear to be really cold in Summer, {343} and hot in
Winter at the bottom of the Mines, by surer proofs than the Testimony of
our Touch?

3. Whether they ever meet with places and Stones actually very hot, as
_Matthesius_ relates? And whether that spring not from the quenching of
_Marchasites_?

4. Whether they find in the Mines any Mineral Gelly, such as the _German_
Naturalists call _Ghur_? And whether in process of time it will harden into
a metal, or Mineral Concretion?

5. What are the Laws, Constitutions, and Customs, _Oeconomical_,
_Political_, _Ethical_, that are receiv'd and practis'd among the Mine-men?

6. Whether the Diggers do ever really meet with any subterraneous _Demons_;
and if they do, in what shape and manner they appear; what they portend;
and what they do, &c?

7. Whether they observe in the Trees and other Plants, growing over or neer
the Mine, not only, (as hath been already intimated) that the Leaves are
any whit gilded or silver'd by the ascending Mineral Exhalations, but also,
that the Trees or other Plants are more solid and ponderous? And if they
have not also some discernable Metalline or Mineral Concretes, to be met
within the small Cavities and Pores of their substance?

8. Whether there be not Springs, and also greater Streams of Water neer the
Mine, that rise, and run their whole course under ground, without ever
appearing above it?

9. Whether the Subterraneous Springs do rise with any wind or determinate
change of weather?

10. How much heavier the _Atmosphere_ is at the bottom of the Mine, than at
the top? And whether Damps considerably increase the weight of it?

11. Whether they find any strange substances in the Mines, as Vessels,
Anchors, Fishes inclos'd in Sparr or Metal, &c.? {344}

       *       *       *       *       *

__Promiscuous Inquiries_, chiefly about _Cold_, formerly sent and
recommended to Monsieur _Heuelius_; together with his Answer return'd to
some of them._

A considerable piece of the grand Design of the Modern _Experimental_
Philosophers being, to procure and accumulate Materials for a good Natural
History, whence to raise in progress of time a solid Structure of
Philosophy; all possible Endevours are used in _England_, to send abroad
and recommend to as many of Forreign parts, as there is opportunity,
_Directions_ for searching into the Operations of Nature, and for observing
what occurs therein, aswell as in Mechanical operations and practices.

Several Heads of that kind have been already publish'd for this purpose in
several of the former Tracts; to which, as we have added, in this, the
_Quæries_ about _Mines_, so we shall subjoyn those, that were not long
since committed to the care of that Excellent Promoter of Astronomy and
Philosophy, Monsieur _Heuelius_, Consul of _Dantzick_; who demonstrates so
much zeal for the advancement of real knowledge, that he not only improves
and promotes it by his own Studies, but labours also to incite others to do
the like; having already warmed many of the Northern Climate, particularly
_Poland_, _Prusse_, _Livonia_, _Sweden_ and _Denmark_, into a disposition
to be studious and active in inquiring after such particulars concerning
Philosophy, as are recommended from hence, and rendred them, very willing
to employ themselves in things of that nature.

_The Inquiries sent to _Dantzick_, are these;_

1. What Signior _Burattini_ (an _Italian_ Gentleman, Master of the Mint to
the King of _Poland_, and reputed a great Master in the _Mechanicks_) hath
perform'd in _Diopticks_? Whether at present he employs himself, as is
related, in grinding a _Telescope_ of 120 foot long? And, if so, what way
he means to make use {345} of, commodiously to handle a Tube of that
length?

2. Whether the same have the Art (as has been written from _Paris_) to make
such Glass, as is not at all inferiour to _Venice_-glass, and exceeds any
plate of Glass, hitherto made there, twice or thrice in bigness?

3. What is the way of making Pot-ashes in _Poland_?

4. What is to be observed about _Succinum_ or Amber? whether it be an
Exsudation of the Sea? whether it be seen to float upon the surface of the
Sea? whether it be soft, when 'tis first cast on shore? At what season of
the year, and in what manner 'tis taken up, &c?

5. What is to be observ'd in the Digging of _Sal Gemmæ_ in _Poland_? what
is the Depth of the Mines, stored with this Salt? what their distance from
the Sea, &c?

6. What truth there is in that Relation concerning Swallows being found in
Winter under waters congealed, and reviving, if they be fish'd and held to
the fire?

7. Whether there be in the _Bodnick Bay_ a Whirl-pool, as is related to be
in the Sea of _Norway_, which is commonly call'd the _Maal-stroom_? And
whether there be any Signs, that speak the communication of those Gulphs by
subterraneous passages; as the Jesuit _Kircher_ affirms in his _Mundus
Subterraneus_ T. 1. p. 146?

8. To what depth the Cold in those parts peirces the Earth and Water?

9. Whether their Watches go slower by the intense cold?

10. Whether their Oyls in hard frosts are turn'd into true, that is, hard
and britle, Ice?

11. Whether they can freeze there a strong Brine of Bay-Salt; and a strong
Decoction of _Sal Gemmæ_, or Soot; or a strong Solution of _Salt_ of
_Tartar_, or of _Sugar_ of _Lead_?

12. Whether they can congeal meer _Blood_, all the serous part thereof
being sever'd? Item, _Canary_ Wine; the _Lixiviums_ of Soap-boylers, and
such as are prepared of other Salts; as also, the Spirits extracted out of
Salts, as Spirit of _Vitriol_, _Nitre_, &c?

13. Whether an intense and lasting Frost makes any alteration in
_Quick-silver_, exposed very shallow in a flat Vessel.

14. Whether the Purgative virtue of _Catharticks_ be increased or lessened,
or even totally destroy'd by a strong and continued Cold? {346}

15. Whether Harts-horn thaw'd, and such like substances, using the same
method of Distilling, yield the same quantity of Liquor, which they use to
yield, when not frozen?

16. What Cold operates in the Fermentation of Liquors?

17. Whether Birds and Wilde Beasts grow white there in Winter, and recover
their native colour in Summer?

18. Whether Colours may be concentred by a sharp cold? _E.g._ A strong
Decoction of Cocheneel in a fit Glass?

19. Whether the _Electrical_ virtue of _Amber_, and the _Attractive_ and
_Directive_ force of the _Magnet_, be changed by a vehement Cold?

20. Whether pieces of Iron and Steel, even thick ones, be made britle by
intense frosts; and therefore Smiths are obliged for prevention, to give
their Iron and Steel-tools a softer temper?

21. Whether accurate Observations evince, that all Fishes dye in frozen
Waters, if the Ice be not broken? Where it is to be diligently inquired
into, whether the Cold it self, or the want of changing or ventilating the
water, or the privation of Air, be the cause of the death of Fishes?

22. Whether any Physicians or Anatomists have inquired, by freezing to
death some Animals (as Rabits, Pullets, Dogs, Cats, &c.) after what manner
it is, that Intense Cold kills men? whether they have found any Ice in the
Inner parts; and if so, in which of them; Whether in the Ventricles of the
Brain and Heart; and in the greater Vessels?

_These were the Queries_ recommended about a Twelve-month ago. Monsieur
_Heuelius_ in a late Letter of his, accompanied with several papers from
others, returns this Accompt.

The Inquiries you proposed to me, I did impart to several of my Learned
friends: But hitherto I have attained an Answer but to few particulars.
Among the rest you'l find a Letter of the Learned _Johannes Schefferus_,
Professor in the _Swedish_ University at _Vpsall_, wherein he discourses
handsomly of several things, being ready to entertain a Literary Commerce
with you about such matters. Touching _Amber_, I am almost of the same mind
with him, that it is a kind of _Fossil Pitch_ or _Bitumen_, seeing it is
not only found on the Shore of the _Borussian_ Sea, but also digg'd up in
subterraneous places, some _German_ miles distant from the {347} and that
not only in Sandy, but also in other Hills of firmer Earth; of which I have
seen my self pretty big pieces. Concerning _Swallows_, I have frequently
heard Fisher-men affirm, that they have here often fish'd them out of the
Lakes, in the Winter; but I never have seen it my self. Whilst I am writing
this, I receive Letters out of _Denmark_, advertising me, that those two
Learned men, _Thomas_ and _Erasmus Bartholin_, do intend shortly to answer
the same _Quæries_. Next Winter, if God vouchsafe me life and health, I
purpose to make a Journey to _Konigs-berg_, where I hope to learn many
things, especially about _Amber_.

    _Thus far in answer to those Inquiries for the present._

To this he subjoyns other things, no less fit to be communicated to the
Curious, in these words;

The Books you have sent me over sea, I have not yet received: I wish, they
were all translated into Latin; for I have not _English_ enough, to
understand all particulars perfectly. For the rest, you have obliged me, by
communicating the Observations of the last _Eclipse_ of the _Sun_, aswell
those made in _England_, as those of _Paris_ and _Madrid_. That I may
requite you in some measure, I send you my Observations both of _that_, and
the _Moons_ last _Eclipse_. In the _Sun's Eclipse_, this is chiefly
observable, That the _Semidiameter_ of the _Moon_ from the very beginning,
to about 5. or 6. digits of the increasing _Phasis_ was much less than the
_Rudolphin_ Account imports. For it was then almost equal to the
_Semidiameter_ of the _Sun_: but, after the greatest Obscuration, when I
again contemplated the _Moons Semidiameter_, I found it 8" or 9" bigger
than that of the _Sun_; so that the _Semidiameter_ of the _Moon_ was not
always, during this Eclipse, constant to it self. It will therefore be
worth while, to be hereafter more diligent and curious in this particular,
and accurately to observe in the _Phasis_ of each _Digit_ the _Proportion_
of the _Semidiameters_ of both Luminaries; to the end, that _first_ it may
be made manifest, Whether in all the _Eclipses_ of the _Sun_, or in some
only, that variation happens; _next_, that the Causes of such a
_Phænomenon_ may be diligently inquired into. Of this Variation, the
Excellent _Ismael Bullialdus_ hath also observed something at _Paris_. For
he has written to me, That in the same Eclipse the _Semidiam._ of the _Sun_
to the _Semid._ of the _Moon_ was, as 16'. 9". to 16'. 22"; but that in
another {348} _Phasis_ of 6 _digits_, the Semidiameters appear'd equal.
These my Observations, if you think them worthy, you may communicate to
other Mathematicians. The last year 1665. _July_ 27. (_st. n._) the
_Tables_ did also indicate an Eclipse of the _Moon_: but though the Sky
here was very cleer, yet the Moon was not at all obscured by the _true
shadow_, but entred only a little into the _Penumbra_, wherein it continued
50'. The beginning of its touching the _Penumbra_ did then almost happen,
when _Aquila_ was elevated 36° 18'; which is an Example worthy to be noted.
I have many Observations of the _Eclipses_ of former years by me, which I
could not yet make publick, by reason of the multitude of my business,
which do almost over-whelm me. The Eclipse of the Moon of this Year 1666.
_June_ 16. (_st. n._) was observed from a Hill neer my Garden, to the end,
that we might see both together the _Suns setting_, and the _Moon rising_.
But I was disappointed of my hopes: For very thick Exhalations, besieging
the _Horizon_, where the Moon was to rise, unto 2°. 30', hindred me from
seeing the _Moon rise_, in the Article of the _setting_ of the _Sun_.
Wherefore the first _Phasis_ of 1. _dig_. 45'. did not appear but in the
_Moons Altitude_ of 2°. 30'; when the greatest Obscuration was already
past. The _End_ fell out hor. 9. 27'. about 128° from the _Zenith_
Westward.

[Sidenote: * A Letter, written since from _Paris_, advertises, that some of
the Curious there have received one of these Glasses of _Sr. Burattini_,
and do esteem it to be good without mentioning the Dimension of it: which
yet is look'd for by the next.]

I am very glad to understand, that you have so good _Telescopes_, as to
make such considerable Observations in _Jupiter_ and _Mars_, as you have
lately done in _England_. I have no leasure now, by reason of the
Observations of the Fixt Stars, which I now almost constantly am employ'd
about, to do any thing in the advancing of _Telescopes_. I am obliged to
finish the _Catalogue_ of the _Fixt Stars_; having mean while the
contentment to find, that many excellent persons labour about the
Improvement of _Optick Glasses_. If I could get a good one of those of 60.
foot, you mention, at a reasonable rate, you would oblige me in sending me
one; perhaps may I be so happy, as to make likewise some good discovery or
other, by the help thereof. In the mean time, let me know, I pray, the
Dimensions of those Glasses, and how they are to be managed. The ingenious
_Burattini_ has not yet finisht his _Telescope_; as soon {349} as he hath,
I shall acquaint you with it. * Before I conclude, I must give notice to
the Lovers of _Astronomy_, that on the 24. of _September_ (st. n) of this
year, I have observ'd that _New Star_ in _Pectore Cygni_ (which from the
year 1662. untill this time hath been almost altogether hid) not only with
my naked Eye, like a Star of the sixth or seventh Magnitude, but also with
a very great _Sextant_. It is still in the very same place of the Heavens,
where it was formerly from _A._ 1601. to almost 1662. For, its Distance
from _Scheat Pegasi_ hath been by me found 35°. 51'. 20". and from
_Marcab_, 43°. 10'. 50"; which Distances (as I have found in my _Journal_)
are altogether equal to those, which I observ'd _A._ 1658. the 1. of
_November_. For the Distance from _Scheat_ at that time was 35°. 51'. 20".
and from _Marcab_, 43°. 10'. 25": where that former from _Scheat_ exactly
answers to the recent; and that from _Marcab_, 'tis true, differs in a very
few _Seconds_, but that disparity is of no moment, since it only proceeded
from thence, that this _New Star_ is not yet so distinctly to be seen, as
at that time, when it was of the _third Magnitude_. It is therefore
certain, that it is the self same Star, which _Kepler_ did first see _A._
1601. and continued untill _A._ 1662. But whether in time it will grow
bigger and bigger, or be lost again, time will shew. He that will observe
this Star, must take care, lest he mistake those three more _Southern_
ones, of the _Sixth Magnitude_, and now in a manner somewhat brighter
(though not extant on the _Globe_) than the _New Star_ in _Collo Cygni_.
The highest of those three, is distant from _Scheat Pegasi_ 36°. 25'. 45";
the middlemost from the same, 37°. 25'. 20". and the lowest, 38°. 4'. 30".
Farewell, and assure the Most Illustrious _Royal Society_ of my humblest
Services.

_So far Monsieur Heuelius_, whose accurate Calcul. of the _Solar Eclipses_
Duration, Quantity, &c. is intended to be fully represented the next Month,
since it could not be conveniently done this time. The _annexed_ Papers
follow.

_One_ is from Monsieur _Joh. Schefferus_, to this purpose.

1. That he is confident, the _Royal Society_ of _England_ will do much good
for the advancement of usefull Knowledge.

{350}

2. That he conceives _Amber_ to be a kind of _Fossil Pitch_, whole Veins
lie at the bottom of the Sea; believing that it is hardned in tract of
time, and by the motion of the Sea cast on shore: _He adds_, that hitherto
it hath been believed, not to be found but in _Borussia_; but he assures,
that it is also found in _Sueden_, on the shores of the Isle _Biorkóó_, in
the Lake _Melero_, whose water is _sweet_. Of this, _he saith_, he hath a
fine piece by him, two inches large and thick, presented him by one, that
himself with his own hands had gathered it and several other pieces, on the
shore of the said Island; affirming withall from the mouth of a Shepherd of
that place, that it is thrown out by a strong Wind, bearing upon the shore.

3. That it is most certain, that _Swallows_ sink themselves towards Autumne
into Lakes, no otherwise than _Frogs_; and that many have assured him of
it, who had seen them drawn out with a Net together with Fishes, and put to
the fire, and thereby revived.

4. That 'tis also very true, that many _Animals_ there grow white in
Winter, and recover their own Colour in Summer. That himself hath seen and
had _Hares_, which about the beginning of Winter and Spring were half
white, and half of their native colour: that in the midst of winter he
never saw any but all white. That _Foxes_ also are white in Winter; and
_Squirrels_ grayish, mixt of dark and white colour.

5. That 'tis known there generally, that _Fishes_ are killed, by reason of
the Ice not being broken: but _first_, in ponds only or narrow Lakes;
_next_, in such Lakes only, where the Ice is pretty thick; for, where 'tis
thin, they dye not so easily. _Lastly_, that those Fishes that lie in slimy
or clayie ground, dye not so soon as others. But, _he adds_, that even in
great Lakes, when 'tis a very bitter Frost, Ice is wont to be broken,
either by the force of the Waves, or of the Imprisoned Vapors, raised by
the agitation of the Water, and then bursting out with an impetuosity;
witness the noise made by the rupture of the Ice through the whole length
of such Lakes, which _he affirms_ to be not less terrible than if many guns
went off together. Whereby it falls out, that Fishes are seldom found dead
in great Lakes.

6. That neither Oyle, nor a strong Brine of Bay-Salt, is truly {351}
congeal'd into Ice, in those parts, _Viz._ at _Upsall_ in _Sueden_.

7. That the Frost pierces into the Earth, two Cubits or _Swedish_ Ells; and
what moisture is found in it, is white, like Ice: That Waters, if standing,
freeze to a greater depth, even to three such Ells or more; but those that
have a Current, less: That rapid Rivers freeze not at all; nor ever-bubling
Springs; and that these latter seem even to be warmer in Winter, than
Summer.

_So far this Observer_; who likewise offers his Services in giving an
answer to the remaining _Queries_, and in entertaining a commerce in such
other Philosophical matters, as he is conversant in.

_Another_ Paper written by Monsieur _Febre_, chief Secretary to Prince
_Ratzivil_, contains these particulars;

1. That the College of the Learned in _Borussia_, finds it not so easie to
resolve all those _Queries_ sent from _England_ to M. _Heuelius:_ but yet
that they will try what may be done upon it.

2. That as for himself, he can assure from his own Experience concerning
the Effects of Cold; _First_, That in the War against the _Muscovites_ and
_Cosacks_, _A._ 1655. in _January_, in _White Russia_, at the Siege of
_Biskow_, 30. Leagues from _Smolensko_, and three from _Morhilo_, near the
River _Boristhenes_, when they had Quarter in a Village call'd _Bikau_,
they were seized on with such a Frost, that all their Provisions of
_Spanish_ Wines or _Petersimen_, and _Beere_, were in one Night frozen upon
the Sleds, notwithstanding they were cover'd with Straw; in so much, that
when next morning they would have drawn of those Liquors, they found all
dry, and were constrain'd to carry them into a Stove, to thaw them; which
they could not do in two whole days, and were obliged to break the Vessels,
and put pieces of the Icy Wine into Kettles to thaw them over the Fire, for
Drink: That they asked not for a Draught, but a _Morsel_ of Wine or Beer:
That their Horses had no better cheer than themselves, as to matter of
Drink; the Pond of the Village being so thoroughly frozen, that there was
but very little Water left between the Ice and the bottom of the Pool;
whereby the poor Beasts were forced to drink with great reverence, kneeling
on the forefeet to thrust their heads into the holes, made for them in the
Ice, and to suck thence some drops of Water; and that, if they had not had
Snow to eat, there would have dyed a far greater {352} number of them, than
there did. Moreover, that he observed, that the _Hungarian Wine_, of which
they had a Tun, resisted the Cold better, than the _Peter Simen_; for it
was not so much frozen; unless it be, that the Butler had more care of
that, than the rest, by transporting it sooner into the Stove, when he
found the excess of Cold. Again, that one presenting him in the March with
some _Aqua-vitæ_, the Scrue of the Flagon, put to his Mouth, stuck so close
to his Lips, that he could not draw it off, without drawing bloud,

In a _third_ Paper, I find these particulars from the same M. _Febre_.

1. That a considerable person, one Dr. _Becker_, a great Lover of Curious
Inquiries, has given him hopes to entertain this Philosophical Commerce.

2. That he hath seen men dye in _Poland_ and _Lithuania_ both of _Heat_ and
_Cold_. And _first_, that _A._ 1653. in _July_, being with this present
King of _Poland_ in march from _Leopoli_ to the Camp of _Glignani_, it was
so furiously hot that day of their march, that it caused such an alteration
in that Regiment of Foot, which was the Kings Guard, marching most of them
bare-foot upon Sands, that more than an hundred of them fell down
altogether disabled, whereof a dozen dyed out-right, without any other
Sickness. _Secondly_, as to the Cold, that the frost was so bitter, that 3
Souldiers dyed of it, _A._ 1665. the 2. of _January_, in passing a long
Ditch: besides, that divers persons lost some of their Lims.

       *       *       *       *       *

_The Success of the Experiment of Transfusing the Bloud of one Animal into
another._

This experiment, hitherto look'd upon to be of an almost unsurmountable
difficulty, hath been of late very successfully perform'd not only at
_Oxford_, by the directions of that expert Anatomist Dr. _Lower_, but also
in _London_, by order of the _R. Society_, at their publick meeting in
_Gresham Colledge:_ the Description of the particulars whereof, and the
_Method_ of Operation, is referred to the next Opportunity.

       *       *       *       *       *


_Errata_ to be corrected in Number 18.

Pag. 311. line 18. read _marked_. p. 312. l. 35. r. _Sines_. ib. l. penult.
_Sines_. p. 313. l. 13. r. _Sines_. p. 316. l. 26. r. _that_ for _if_.

       *       *       *       *       *


_London_, Printed for _John Crook_ neer the _Blew-Anchor_ in _Duck-lane_;
and _Mose Pits_ at the _White-Hart_ in _Little-Britain_.

{353}

       *       *       *       *       *




_Numb._ 20.

PHILOSOPHICAL
_TRANSACTIONS._

       *       *       *       *       *

_Munday_, _December_ 17. 1666.

       *       *       *       *       *

The Contents.

    _The Method observed in _Transfusing the Bloud out of one live Animal
    into another_: And how this Experiment is like to be improved. Some
    Considerations concerning the same. An Accompt of some Sanative Waters
    in _Herefordshire_. A farther Accompt of the _Vitriolate_ Water
    mention'd _Numb. 18_. together with some other particulars touching
    Waters. Inquiries for _Turky_. An Observation about Optick Glasses made
    of Rock-Crystal, communicated from _Italy_. A Relation of the Use of
    the Grain of _Kermes_ for _Coloration_, from _France_. An Accompt of
    some Books lately publisht, _vid. 1_. PINAX Rerum Naturalium
    BRITANNICARUM, continens VEGETABILIA, ANIMALIA & Fossilia ANGLIÆ,
    inchoatus; Auth. _Christophoro Merret_, M.D. _2_. PLACITA PHYLOSOPHICA
    _Guarini. 3_. GUSTUS ORGANUM per _Laurentium Bellini_ deprehensum._

       *       *       *       *       *

The Method observed in _Transfusing the Bloud of one Animal into another._

This Method was promised in the last of these Papers. It was first
practiced by Dr. _Lower_ in _Oxford_, and by him communicated to the
Honourable _Robert Boyl_, who imparted it to the _Royal Society_, as
follows;

First, Take up the _Carotidal_ Artery of the Dog or other Animal, whose
Bloud is to be transfused into another of the {354} same or a different
kind, and separate it from the Nerve of the _Eighth pair_, and lay it bare
above an inch. Then make a strong Ligature on the _upper_ part of the
Arterie, not to be untied again: but an inch below, _videl._ towards the
Heart, make another Ligature of a _running_ knot, which may be loosen'd or
fastned as there shall be occasion. Having made these two knots, draw two
threds under the Artery between the Ligatures; and then open the Artery,
and put in a Quil, and tie the Artery upon the Quill very fast by those two
threds, and stop the Quill with a stick. After this, make bare the
_Jugular_ Vein in the other Dog about an inch and a half long; and at each
end make a Ligature with a running knot, and in the space betwixt the two
running knots drawn under the Vein two threds, as in the other: then make
an Incision in the Vein, and put into it two Quills, one into the
_descendent_ part of the Vein, to receive the bloud from the other Dog and
carry it to the Heart; and the other Quill put into the other part of the
_Jugular_ Vein, which comes from the Head (out of which, the second Dogs
own bloud must run into Dishes.) These two Quills being put in and tied
fast, stop them with a stick, till there be occasion to open them.

All things being thus prepar'd, the Dogs on their sides towards one another
so conveniently, that the Quill may go into each other, (for the Dogs necks
cannot be brought so near, but that you must put two or three several
Quills more into the first two, to convey the bloud from one to another.)
After that unstop the Quill that goes down into the first Dog's _Jugular_
Vein, and the other Quill coming out of the other Dog's Artery; and by the
help of two or three other Quills, put into each other, according as there
shall be occasion, insert them into one another. Then flip the running
knots, and immediatly the bloud runs through the Quills, as through an
Artery, very impetuosly. And immediately, as the bloud runs into the Dog,
unstop the other Quill, coming out of the _upper_ part of his _Jugular_
Vein (a Ligature being first made about his Neck, or else his other
_Jugular_ Vein being compress'd by ones Finger;) and let his own bloud run
out at the same time into Dishes (yet not constantly, but according as you
perceive him able to bear it) {355} till the other Dog begin to cry, and
faint, and fall into Convulsions, and at last dye by his side.

Then take out both the Quills out of the Dogs _Jugular_ Vein, and tye the
running knot fast, and cut the Vein asunder, (which you may doe without any
harm to the Dog, one _Jugular_ Vein being sufficient to convey all the
bloud from the Head and upper parts, by reason of a large _Anatomosis_,
whereby both the _Jugular_ Veins meet about the _Larinx_.) This done, sow
up the skin and dis-miss him, and the Dog will leap from the Table and
shake himself and run away, as if nothing ailed him.

And this I have tryed several times, before several in the _Universities_,
but never yet upon more than one Dog at a time, for want of leisure, and
convenient supplyes of several Dogs at once. But when I return, I doubt not
but to give you a fuller account, not only by bleeding several Dogs into
one, but several other creatures into one another, as you did propose to
me, before you left _Oxford_; which will be very easie to perform; and will
afford many pleasant and perhaps not unuseful Experiments.

But because there are many Circumstances necessary to be observ'd in the
performing of this Experiment, and that you may better direct any one to
doe it, without any danger of killing the other Dog, that is to receive the
others bloud, I will mention two or three.

_First_, that you fasten the Dogs at such a convenient distance, that the
Vein nor Artery be not stretched; for then, being contracted, they will not
admit or convey so much bloud.

_Secondly_, that you constantly observe the Pulse beyond the Quill in the
Dogs _Jugular_ Vein (which it acquires from the impulse of the _Arterious_
bloud:) For if that fails, then 'tis a sign the Quil is stopt by some
congealed bloud, so that you must draw out the _Arterial_ Quill from the
other, and with a _Probe_ open the passage again in both of them, that the
bloud may have its free course again. For, this must be expected, when the
Dog, that bleeds into the other, hath lost much bloud, his heart will beat
very faintly, and then the impulse {356} of bloud being weaker, it will be
apt to congeal the sooner, so that at the latter end of the work you must
draw out the Quill ofter, and clear the passage; if the Dog be
faint-hearted, as many are, though some stout fierce Dogs will bleed freely
and uninterruptedly, till they are convuls'd and dye. But to prevent this
trouble, and make the experiment certain, you must bleed a great Dog into a
little one, or a _Mastive_ into a _Curr_, as I once try'd, and the little
Dog bled out at least double the quantity of his own bloud, and left the
_Mastive_ dead upon the Table, and after he was untyed, he ran away and
shak'd himself, as if he had been only thrown into water. Or else you may
get three or four several Dogs prepared in the same manner; and when one
begins to fail and leave off bleeding, administer another, and I am
confident one Dog will receive all their bloud, (and perhaps more) as long
as it runs freely, till they are left almost dead by turns: provided that
you let out the bloud proportionably, as you let it goe into the Dog, that
is to live.

_Thirdly_, I suppose the Dog that is to bleed out into dishes will endure
it the better, if the Dogs that are to be administred to supply his bloud,
be of near an equal age, and fed alike the day before, that both their
blouds may be of a neer strength and temper.

There are many things I have observed upon bleeding Dogs to death, which I
have seen since your departure from _Oxford_, whereof I shall give you a
relation hereafter; in the mean time since you were pleased to mention it
to the _Royal Society_, with a promise to give them an account of this
experiment, I could not but take the first opportunity to clear you from
that obligation, &c.

_So far this Letter;_ the prescriptions whereof having been carefully
observ'd by those who were imployed to make the Experiment, have hitherto
been attended with good success; and that not only upon Animals of the same
_Species_ (as two Dogs first, and then two Sheep) but also upon some of
very differing _Species_ (as a Sheep and a Dog; the former _Emitting_, the
other _Receiving_)

_Note_ only, that instead of a Quill, a small crooked thin {357} Pipe of
Silver or Brass, so slender that the one end may enter into a Quill, and
having at the other end, that is to enter into the Vein and Arterie, a
small knob, for the better fastening them to it with a thread, will be much
fitter than a strait Pipe or Quill, for this Operation: for so they are
much more easie to be managed.

'Tis intended, that these tryals shall be prosecuted to the utmost variety
the subject will bear: As by exchanging the bloud of Old and Young, Sick
and Healthy, Hot and Cold, Fierce and Fearful, Lame and Wild Animals, &c.,
and, that not only the same, but also of differing kinds. For which end,
and to improve this noble Experiment, either for knowledge, or use, or
both, some Ingenious men have already proposed considerable tryals and
Inquiries; of which perhaps an account will be given hereafter. For the
present we shall only subjoyn some.

_Considerations about this kind of Experiments._

1. It may be consider'd in them, that the bloud of the _Emittent_ Animal,
may after a few minuts of time, by its circulation, mix and run out with
that of the _Recipient_. Wherefore to be assured in these Tryals, that all
the bloud of the _Recipient_ is run out, and none left in him but the
adventitious bloud of the _Emittent_, two or three or more Animals (which
was also hinted in the _method_ above) may be prepared and administred, to
bleed them all out into one.

2. It seems not irrational to guess afore hand, that the exchange of bloud
will not alter the nature or disposition of the Animals, upon which it
shall be practised; though it may be thought worth while for satisfaction
and certainty, to determine that point by Experiments. The case of
exchanging the bloud of Animals seems not like that of _Graffing_, where
the _Cyons_ turns the Sap of the _Stock_, graffed upon, into its nature;
the _Fibres_ of the Cyons so straining the juice, which passes from the
stem to it, as thereby to change it into that of the Cyons, whereas in this
transfusion there seems to be no such {358} Percolation of the bloud of
Animals, whereby that of the one should be changed into the nature of the
other.

3. The most probable use of this Experiment may be conjectured to be that
one Animal may live with the bloud of another; and consequently, that those
Animals, that want bloud, or have corrupt bloud, may be supplyed from other
with a sufficient quantity, and of such as is good, provided the
Transfusion be often repeated, by reason of the quick expence that is made
of the bloud.

       *       *       *       *       *

Note.

_In the last _Transactions_ was also promised an Accompt by the next, of
Monsieur _Hevelius_ his accurate Calcul. of the late _Solar Eclipses_,
Duration, Quantity, &c. But this being to be accompanyed with _Scheme_, the
_Graving_ whereof met with a disappointment, it must be still referred to
another Opportunity._

       *       *       *       *       *

_An Accompt of some Sanative-waters in _Herefordshire_._

This account was communicated by Dr. _B._ in these words.

There are two Springs in _Herefordshire_, whereof one is within a Bolt, or
at least Bow-shoot of the top of the near adjoyning loftie Hill of
_Malvern_, and at great distance from the Foot of the Hill; and hath had a
long and old fame for healing of eyes. When I was for some years molested
with Tetters on the back of one and sometimes of both my hands,
notwithstanding all endeavors of my very friendly and skilful Physitians I
had speedy healing from a neighbouring Spring of far less fame. Yet this
Spring healed very old and Ulcerous sores on the Legs of a poor Fellow,
which had been poyson'd by Irons in the Gaol, after other Chirurgery had
been hopeless. And by many tryals upon my hands, and the Tetters; I was
perswaded, that in long droughts, and lasting dry Frosts, those waters were
more effectually and more speedily healing, than at other times. And not to
omit this circumstance, I did hold this water in my mouth, till it was
warm, perchance somewhat intermingled with fasting Spittle, {359} and so
dropping it upon the Tetter, I there could see it immediately gather a very
thin skin upon the raw flesh, not unlike that which is seen to gather upon
Milk over a gentle fire. This skin would have small holes in it, through
which a moisture did issue in small drops, which being wip'd away, and the
water continued to be dropp'd warm out of the mouth, the holes would
diminish, and at last be all quite healed up.

For the _Eye-waters_, I conceived them more strongly tersive, and clearing
the Eyes; and they had a rough smartness, as if they carryed Sand or Gravel
into the Eye.

I have known and try'd three or four healing Fountains of late discovery,
or of no old fame that I could hear of.

I did once put rich _Marle_ for some days in a vessel of water, to try
whether the water would acquire a healing vertue, but my Experiments were
interrupted. I had in my thoughts many other ways of Tryal; which I may
resume hereafter.

       *       *       *       *       *

_A farther Accompt of the _Vitriolate-water_, mention'd _Num. 18 p. 323_.
Together with some other particulars touching waters._

This comes from the same hand as follows;

I formerly mentioned to you, that, if that Pool of Mr. _Phillip's_, which
seems to be of Vitriolate-water, were on my ground, I would drain it, and
search the head of the Spring, pursuing the source, till I could well
discern, through what lay of Earth or Gravel it does pass. Now I shall tell
you, that I have taken order for the further tryal of the said Water, by
boiling a greater quantity in a Furnace, &c. But just as we were in
readiness for the tryal, a stream of Rain-water fell into the Pool, and so
discourag'd us for the present. I have also taken a course to turn the
falling Waters aside, and to drain the Pool, that we may see, what the
Native Springs (whether one or more) may be. Of which more hereafter.

I wish (_so he goes on_) we had a full Accompt of our _Salt-Springs_ at
_Droyt-wych_ near _Worcester_, and at _Nant-wych_ in _Cheshire_ (what other
Salt-Springs we have in _England_, I know not:) {360} It should be
inquired, at what distance they are from the Seas, or from Salt-fluxes,
from Hills, and how deep in the Vales? What the weight? Whether in droughts
or long Frosts the proportion of Salt or weight increaseth? Whether the
Earth near the Springs, or in their passage hath any peculiar ferment, or
produceth a blackishness, if it rests, after it is well drained.

       *       *       *       *       *

_Inquiries for _Turky_._

Though many Relations and Descriptions of _Turky_ be extant in Print, yet
they leave in many a desire of a fuller information in the following
particulars, lately drawn up, for the most part by Mr. _H._ and recommended
to an Ingenious Gentleman, bound for that Country; and desired also to be
taken notice of by others, that may have occasion to visit the same.

[Sidenote: * _Rusma_ is a kind of Earth, used in _Turky_ to take away
hair.]

1. In what part of _Turky_ the * _Rusma_ is to be found; and in what
quantity? Whether the _Turks_ employ it to any other Uses, besides that of
the taking away of Hair? Whether here be differing kinds of it? How it is
used to take of hair, and how to get store of it.

2. Whether the _Turks_ do not only take _Opium_ themselves for strength and
courage, but also give it to their Horses, Camels and Dromedaries, for the
same purpose, when they find them tired and faint in their travelling? What
is the greatest _Dose_, any men are known to have taken of _Opium_? and how
prepared?

3. What effects are observed from their use, not only of _Opium_ (already
mention'd) but also of Coffee, Bathing, shaving their Heads, using Rice;
and why they prefer that which grows not unless water'd, before Wheat, &c.

4. How their Damasco steel is made and temper'd?

5. What is their way of dressing and making Leather, which though thin and
supple, will hold out water?

6. What method they observe in breeding those excellent Horses, they are so
much famed for?

7. Whether they be so skilful in Poysoning, as it is said; and how their
Poysons are curable?

{361}

8. How the _Armenians_ keep Meat fresh and sweet so long, as 'tis said they
do?

9. What Arts or Trades they have worth Learning?

10. Whether there be such a Tree about _Damascus_, call'd _Mouslat_, which
every year about the Month of _December_ is cut down close by the root, and
within four or five Months time shoots up again apace, bringing forth
Leaves, Flowers, and Fruit also, and bearing but one Apple (an excellent
Fruit) at once?

11. Whether about _Reame_ in the Southern part of _Arabia Foelix_, there be
Grapes without any grains? And whether the people in that Country live,
many of them, to a hundred and twenty years, in good health?

12. Whether in _Candia_ there be no poysonous Creatures; and whether those
Serpents, that are there, are without poyson?

13. Whether all Fruits, Herbs, Earth, Fountains, are naturally saltish in
the Isle of _Cyprus_? And whether those parts of this Isle, which abound in
_Cyprus-trees_, are more or less healthful, than others?

14. What store of _Amianthus_ there is in _Cyprus_; and how they work it?

15. Whether _Mummies_ be found in the sands of _Arabia_, that are the dryed
flesh of men buried in those sandy Deserts in travelling? And how they
differ in their vertue from the Embalmed ones?

16. Whether the parts about the City of _Constantinople_ or _Asia Minor_,
be as subject to Earth-quakes now, as they have been formerly? And whether
the Eastern Winds do not Plague the said City with Mists, and cause that
inconstancy of Weather, it is said to be subject to?

17. Whether the Earth-quakes in _Zant_ and _Cephalonia_ be so frequent, as
now and then to happen nine or ten times a Month? And whether these Isles
be not very Cavernous?

18. What is the height of Mount _Caucasus_, its position, temper in its
several parts, &c.

19. With what declivity the Water runs out of the _Euxine-Sea_ into the
_Propontis_? With what depth? And if the many Tides and Eddies, so famous
by the name of the _Euripi_, have any certain Period? {362}

20. If in the _Euxine-Sea_ there can be found any sign of the _Caspian
Seas_ emptying it self into it by a passage under ground? If there be any
different Colour, or Temper as to Heat or Cold; or any Current or Motion in
the Water, that may give light to it?

21. By what Inland passages they go to _China_; there being now a passage
for _Caravans_ throughout those places, that would formerly admit of no
Correspondence by reason of the Barbarisme of the Inhabitants?

22. Whether in the Aquæducts, they make, they line the inside with as good
Plaister, as the Ancients did? and how theirs is made?

23. To inquire after these excellent works of Antiquity, of which that
Country is full, and which by the ignorant are not thought worth notice or
preservation? And particularly, what is the bigness and structure of the
Aquaeducts, made in several places about _Constantinople_ by _Solyman_ the
Magnificent? &c.

       *       *       *       *       *

_An Observation of Optick Glasses made of _Rock-Chrystal_._

This is contained in a Letter of _Eustachio Divini_, Printed in _Italian_
at _Rome_, as the _39. Journal des Scavans_ extracts it, _vid._

[Sidenote: * It may be queried whether those were true Veins, or only
Superficial Strictures, and slight scratches.]

Though it be commonly believed, that _Rock-Christal_ is not fit for
Optick-Glasses, because there are many Veins in it; yet _Eustachio Divini_
made one of it, which _he saith_ proved an excellent one, though full of
Veins. *

       *       *       *       *       *

_An Accompt of the Use of the Grain of _Kermes_ for Coloration._

This was communicated by the Ingenious Dr. _Croon_, as he received it from
one Monsieur _Verny_, a _French_ Apothecary at _Montpelier_; who having
described the Grain of _Kermes_, to be an excrescence growing upon the
Wood, and often upon the {363} leaves of a Shrub, plentifull in
_Languedock_, and gather'd in the end of _May_, and the beginning of
_June_, full of a red Juyce; subjoyns two Uses, which that Grain hath, the
one for _Medicine_, the other for _Dying of Wool_. Waving the _first_,
notice shall only be taken here of the _latter_, vid. That, for _Dying_,
they take the Grain of _Kermes_, when ripe, and spread it upon Linnen: And
at first, whilst it abounds most in moisture, 'tis turn'd twice or thrice a
day, to prevent its Heating. And when there appears red powder amongst it,
they separate it, passing it through a Searce; and then again spread abroad
the Grain upon Linnen, untill there be perceived the same redness of the
powder; and at the end, this red power appears _about_ and _on_ the surface
of the Grain, which is still to be pass'd through a Searce, till it render
no more.

And in the beginning, when the small red Grains are seen to move (as they
will do) they are sprinkled over with strong Vinegar, and rubb'd between
ones hands: afterwards little balls are form'd thereof, which are expos'd
to the Sun to dry.

If this red powder should be let alone, without pouring Vinegar or some
other accid liquor upon it, out of every Grain thereof would be form'd a
little Fly, which would skip and fly up and down for a day or two, and at
last changing its colour, fall down quite dead, deprived of all the
bitterness, the Grains, whence they are generated, had before.

The Grain being altogether emptyed of its pulp or red powder, 'tis wash'd
in Wine, and then expos'd to the Sun Being well dryed, 'tis rubb'd in a
Sack to render it bright; and then 'tis put up in small Sacks, putting in
the midst, according to the quantity, the Grain has afforded, 10. or 12.
pounds (for a _Quintal_) of the dust, which is the red powder, that came
out of it. And accordingly, as the Grain affords more or less of the said
powder, Dyers buy more or less of it.

'Tis to be noted, That the first red powder, which appears, issues out of
the Hole of the Grain, that is on the side, where the Grain adhered to the
Plant. And that, which about the end appears sticking on the Grain, hath
been alive in the husk, having pierced its covers though the hole, whence
it commonly issues, remains close as to the Eye. {364}

       *       *       *       *       *

_An Account of Some Books lately published._

1. _PINAX Rerum Naturalium BRITANNICARUM, continens VEGETABILIA, ANIMALIA &
FOSSILIA in hoc Insula reperta, inchoatus, Auth._ Christophoro Merret,
_Med. D. & utriusque_ Societatis Regiæ _socio._

The Learned and Inquisitive Author of this Book, hath by his laudable
example of collecting together, what Natural things are to be found here in
_England_, of all sorts (which he has done upon his own expences) given an
invitation to the curious in all parts of the world to attempt the like,
thereby to establish the much desired and highly useful commerce among
_Naturalists_, and to contribute every where to the composing of a genuine
and full _History of Nature_.

In the _Preface_ he intimates, that his stock does still encrease dayly;
and that therefore the Reader may expect an _Appendix_ to this collection.

In the Body of the Book, he enumerates all the _Species_, Alphabetically:
And, as to _Vegetables_, he reckons up about 410 sorts; and gives their
_Latine_ and _English_ Names, and the _Places_ and _Times_ of their growth:
reducing them afterwards to certain _Classes_, hitherto used by _Botanick_
Writers in their _Histories_ of _Plants_: Adding the _Etymology_ of their
Generick Names, and a compendious _Register_ of the Time, _when_ and _how
long_ the _English_ Plants do shoot and flourish.

As to _Animals_, he finds of them about 340 kinds in _England_, whereof the
_fourfooted_ are about 50, _Birds_ 170, and _Fishes_ 120. _Insects_ are
innumerable, which yet he endeavours to enumerate, and to reduce to certain
_Classes_; into which he also brings the three former kinds.

Concerning _Fossils_, he _first_ takes notice of the _Metals_ found in
_English_ Mines; as _Silver, Tin, Copper, Iron, Lead, Antimony_, and some
_Gold_ extracted out of _Tin_. Next of the _Stones_, of which he finds
about 70 sorts; & amongst them, _Bristol Diamonds, Agates, Hyacinths,
Emerods, Loadstones, Toad-stones_, (which last yet he affirms to be nothing
but the grinding-teeth of the {365} Fish _Lupus_) _Pearls, Corals, Marble,
Alablaster, Emery:_ To which he adds the various kinds of _Coals_; as also
_Bitumens, Turfs_ and _Jets_. And _thirdly_ of the various kinds of _Allam,
Vitriol, Niter, Sea-salt, Pit-salt_. But _fourthly_ of the various
_Earths_, of which he reckons up 15. peculiar sorts (besides those that
serve for _Husbandry_, which are not easily numbred;) and amongst them,
_Read-lead, Black-lead_ and _Fullers-earth_.

He concludes all with mentioning the several _Meteors_ appearing in
_England_; and the _Hot springs_; and _Medical Waters_; as also, the
_Salin, Petrifying_, and some more unusual Springs: _Item, Subterraneous
Trees, Subterraneous Rivers, Ebbings and Flowings of Wells_, &c.



II. _PLACITA PHILOSOPHICA Guarini._ The chief subject of this Treatise is
Natural _Philosophy_; upon many important questions whereof it enlargeth,
as those of the Motion of the Coelestial Bodies, of Light, of Meteors, and
of the vital and animal functions; leaving sometimes the common opinions,
and delighting in the defence of _Paradoxes_.

_E. G._ That the material substantial Form, is nothing but _mera potentia_,
and subsists not by it self: by which means the Author judges, he can free
himself from many great difficulties touching _Generation_ and
_Corruption_, which do perplex the other Philosophers.

He holds _Epicycles_ to be impossible, and _Excentricks_, not sufficient to
explicate the motion of the Stars; but that all the irregularities of this
motion may be salved by the means of certain _Spiral_ Lines; largely
proving this _Hypothesis_, and particularly explicating the motion of each
Planet.

He denies the middle Region of the Air to be cold; and believes that cold
is not necessary to condense the vapours into Water.

He admits not that received Axiome, _That the generation of one Body is the
corruption of another_; maintaining that there are _Generations_, to which
no corruption ever preceded; and that it may happen, that one Animal
without dying may be changed into another Animal.

He alledges several reasons to evince, that the Air breathed in, enters not
only into the whole capacity of the Chest, but also into the lower belly.
{366}

He is of opinion that the Air, which is commonly believed to corrupt
easily, is incorruptible; alledging among other reasons, this for one, that
experience shews, that if a Bottle be exactly stop'd, there is never any
mixt Body form'd in it; wherefore, _saith he_, the Air is not corrupted
there.

He maintains, that 'tis not the _Magnet_ that draws the Iron, but rather
the Iron that attracts the _Magnet_. To explain which he affirms, that the
Load-stone spreads abroad out of it self many corpuscles, which the
substance of the Iron imbibes, and that, as dry things attract those that
are moist, by the same reason Iron drawn the Loadstone.

He rejects the _species intentionales_, _Vital_ and _Animal_ Spirits, and
holds many other uncommon opinions, touching _Light_, the _Iris_, the _Flux
and Reflux of the Sea_, &c.



III. _GUSTUS ORGANUM per _Laurentium Bellini_ novissimè deprehensum._

The Author proposing to himself to discover both the principal _Organ_ of
the _Taste_, and the nature of its _object_, begins with the latter, and
examins first, what is _Taste?_ He judges that it is caused by nothing but
Salts, which being variously figured, affects the tongue variously:
alledging this for his chief reason, that the Salt which is extracted by
_Chymists_ out of any mixt body whatever it be, carries away with it all
its taste, and that the rest remains tasteless. He adds that the Teeth in
grinding the Food, serve much to extract this Salt: And he notes by the by,
that the Teeth are so necessary for preparing the aliment, that certain
Animals which seem to have none, have them in their stomach; and that
nature has put at the entry of the palat of those that are altogether
destitute of them, certain moveable inequalities, which are to them instead
of Teeth.

But then _secondly_, concerning the _Organ_ of Taste, he esteems, that 'tis
neither the Flesh, nor the Tongue, nor the Membrans, nor the Nerves found
there, nor the Glanduls, called _Amygdalinæ_; but those _little eminences_
that are found upon the tongue of all Animals. To obtain which, he
observes,

1. That from the middle of the Tongue to the root, as also towards the tip,
there are found innumerable _little Risings_ {367} called _Papillares_; but
that from the tip of the Tongue unto the string there is observed none at
all.

2. He hath experimented, that if you put _Sal Armoniack_ upon the places of
the Tongue, where those _Eminencies_ are not, you shall find no Taste; but
that you will find it presently assoon as you put any such Salt, where they
are to be met with. Ergo, _saith he_, those _Eminencies_ are the principal
Organ of Taste.

3. He assures, that with a _Microscope_, may be seen in those _Risings_
many little holes, at the bottom whereof there are small nerves,
terminating there: But _he directs_, to observe this in live and healthy,
not in dead or sick Animals.

Having laid down these Observations, he concludes, that the manner, after
which Taste is perform'd, is this, That the particles of Salt passing
through those pores, which pierce the _Papillary Eminences_, and
penetrating as far as to the nerves, that meet them there, do by the means
of their small points prick them; which pricking is called the _Taste_.

In the mean time he acknowledges, that before him Signior _Malphigi_,
Professor at _Messina_, had made some of these discoveries.

The notice of these two last Books we owe to the _French Journal_.

       *       *       *       *       *


_Correct in Number._ 19.

Page, 342. line, 33. read _mixt Ores_, in stead of, _mixt with Ores_.

       *       *       *       *       *


_London_, Printed for _John Martin_, Printer to the _Royal Society_, and
are to be sold at the _Bell_ a little without _Temple-Bar_.

{369}

       *       *       *       *       *




_Numb._ 21.

PHILOSOPHICAL
_TRANSACTIONS._

       *       *       *       *       *

_Munday_, _January_ 21. 1666.

       *       *       *       *       *

The Contents.

    _An Account, formerly promised, of Monsieur _Hevelius's_ Calculation of
    the late _Solar Eclipse's_ Quantity, Duration, &c. The Figure of the
    Star in the Constellation of _Cygnus_, together with the New Star in
    it, discovered some years ago, and very lately seen again by the same
    Mr. _Hevelius_. An Extract of a Letter, written by Mr. _Auzout_,
    concerning a way of his, for taking the _Diameters_ of the Planets, and
    for knowing the _Parallax_ of the _Moon_: Giving also a Reason, why in
    the _Solar Eclipse_ above-mentioned, the _Diameter_ of the _Moon_ did
    increase about the end. A Relation of the loss of the Way to prepare
    the _Bononian Stone_ for shining. A Description of a _Swedish Stone_,
    affording _Sulphur, Vitriol, Allum_, and _Minium_. A Relation of the
    Raining of Ashes. An Extract of a Letter from _Rome_, rectifying the
    Relation of _Salamanders_ living in Fire. An Account of several
    Engagements for _Observing of Tydes_. Some Suggestions for Remedies
    against Cold. A Relation of an uncommon accident in two Aged Persons.
    An Account of Two Books, _I. ISMAELIS BULLIALDI ad Astronomos Monita
    duo: Primum, de Stella Nova, in _Collo Ceti_ ante aliquot annos visa.
    Alterum, de Nebulosa Stella in _Andromedæ_ Cinguli parte _Borea_, ante
    biennium iterum ortâ. II. ENTRETIENS sur les vies & sur les Ouvrages
    des plus excellens Peintres, antients & modernes, par M. FELIBIEN_._

       *       *       *       *       *

_Monsieur _Hevelius_'s Calculation of the late _Solar Eclipse's_ Quantity,
Duration, &c._

This _Calculus_ was not long since communicated by Monsieur _Hevelius_ in a
Letter to the _Publisher_, as follows, {370}

_Eclipsis Solaris._

_Observata An. 1666. D. 2. Julii, St. N. Mane, à Johanne Hevelio._

  ----+-----------------+-----------+----------+--------+--------+----
  Ordo|                 |Temp æstin |          |Altitude|        |
  Pha-|Quantitas        |sec. horol |Temp. sec.| [Sun]  |Tempus  |
  sium|Phasium          |ambulat.   |Sciother. |        |correct.|Anim.
  ----+-----------------+-----------+----------+--------+--------+----
      |                 |H. '  "    |H. '  "   | °. '   |H. '  " |
      |                 |5.51.11    |5.51. 0   |17.45   |5.53.12 | 1.
      |                 |5.57. 5    |5.57. 0   |18.37   |5.59.28 |
      |                 |6. 0. 0    |6. 0. 0   |18.55   |6. 1.28 |
  ----+-----------------+-----------+----------+--------+--------+----
      |Initium          |6.55.30    |          |        |6.57.30 | 2.
    1 |0-3/8 dig.       |6.57.30    |          |        |5.59.30 |
    2 |0-3/4            |7. 0.23    |7. 0. 0   |        |7. 2.23 |
    3 |1-1/8            |7. 2.30    |7. 2. 0   |        |7. 4.30 |
  ----+-----------------+-----------+----------+--------+--------+----
    4 |1-1/2 dig.       |7. 4.50    |7. 5 ferè.|        |7. 6.50 |
    5 |1-3/8 ferè.      |7.10.57    |7.10      |        |7.12.57 |
    6 |3-3/8            |7.14.59    |7.15      |        |7.16.59 |
    7 |3-3/4            |7.17.50    |7.18 ferè.|        |7.19.50 |
  ----+-----------------+-----------+----------+--------+--------+----
    8 |4-3/8 dig.       |7.21.35    |7.21      |        |7.23.35 |
    9 |4-2/3            |7.23.43    |7.23 ferè.|        |7.25.43 |
   10 |5-1/4            |7.27.53    |7.28      |        |7.29.53 | 3.
   11 |6                |7.31.50    |7.32      |        |7.33.50 |
  ----+-----------------+-----------+----------+--------+--------+----
   12 |6-3/4            |7.36.55    |7.37      |        |7.38.55 |
   13 |6-7/8 paul. plus.|7.38. 5    |7.38      |        |7.40. 0 |
   14 |7-1/8            |7.39.45    |7.39      |        |7.41.45 |
   15 |7-1/4 paul. plus.|7.42.30    |7.42      |        |7.44.30 |
  ----+-----------------+-----------+----------+--------+--------+----
   16 |7-1/2            |7.44. 6    |7.44      |        |7.46. 6 |
   17 |7-2/3            |7.46. 0    |7.46      |        |7.48. 0 |
   18 |8 ferè           |7.48.25    |7.48 ferè |        |7.50.25 |
   19 |8-1/5            |7.51.15    |7.51      |        |7.53.15 |
  ----+-----------------+-----------+----------+--------+--------+----
   20 |8-1/4 paul. plus.|7.53.37    |7.52      |        |7.55.37 |
   21 |8-3/4            |7.55.45    |7.56 ferè |        |7.57.45 |
   22 |8-3/4 paul. min. |7.59. 5    |7.59      |        |8. 1. 5 | 4.
   23 |8-1/5            |8. 6.30    |8. 6      |        |8. 8.30 |
  {371}
  ----+-----------------+-----------+----------+--------+--------+----
   24 |7-3/4            |8.11.25    |8.12      |        |8.13.25 | 5.
   25 |7-1/4 ferè.      |8.17.30    |8.18      |        |8.19.30 |
   26 |7 ferè.          |8.19.41    |8.19      |        |8.21.41 |
   27 |5-7/8            |8.28. 8    |8.28      |        |8.30. 8 |
  ----+-----------------+-----------+----------+--------+--------+----
   28 |5-1/2 ferè.      |8.30.14    |8.30      |        |8.32.14 |
   29 |4-3/4            |8.36.25    |8.36      |        |8.38.25 |
   30 |3-5/8            |8.43.19    |8.43      |        |8.45.19 |
   31 |3-1/4            |8.46.12    |8.46 ferè.|        |8.48.12 |
  ----+-----------------+-----------+----------+--------+--------+----
   32 |3                |8.47.32    |8.47      |        |8.29.32 |
   33 |2-3/4            |8.50.57    |8.50      |        |8.52.57 |
   34 |2-1/2 ferè       |8.54.15    |8.54      |        |8.56.15 |
   35 |1-3/4            |8.58.24    |8.58      |        |9. 0.24 |
  ----+-----------------+-----------+----------+--------+--------+----
   36 |1-1/8            |8.59.35    |8.59      |        |9. 1.35 |
   37 |0-5/6            |9. 1.38    |9. 1      |        |9. 3.38 |
   38 |0-1/2            |9. 3.20    |9. 3      |Altit.  |9. 5.20 |
   39 |Finis.           |9. 6.53    |9. 6      |[Sun]   |9. 8.53 | 6.
  ----+-----------------+-----------+----------+--------+--------+----
      |                 |9.23. 6    |          |47.33   |9.25 28 |
      |                 |9.24.16    |          |47.42   |9.26.45 |
      |                 |9.28.29    |          |48.10   |9.30.42 |
      |                 |9.30.36    |          |48.28   |9.33.12 |

_Animadvertenda._

1. Quòd Sciatericum cum correcto tempore non omnino convenit, non-nisi
Lineæ Meridianæ imputandum.

2. Initium circa 79 gr. à puncto _Zenith_ occasum versùs contigit.

3. Hujusque Semidiameter Lunæ æqualis extitit Solari.

4. Maxima obscuratio extitit digit. 8.25' hora 8.2'.

5. Hic Semidiameter _Lunæ/_ ad 8" vel 9" major apparuit.*

* _See Numb. 19 of the Philosophical Transactions, p. 347._

6. Punctum finis distitit à verticali ad Ortum 143 gr.

This Observation is by the same _Astronomer_, represented also by the
_Figures AAAAAA_; as that of the _Horizontal Eclipse_ of the _Moon_, is, by
the _Figures BB_.

[Illustration]

[Illustration]

[Illustration]

[Illustration]

{372}

       *       *       *       *       *

_The Figure of the Stars in the Constellation of _Cygnus_; together with
the _New Star_ in it, discover'd some years since, and very lately seen by
M. _Hevelius_ again._

The Relation concerning this _New Star_ in the _Brest of Cygnus_, very
lately discover'd again at _Dantzick_, by M. _Hevelius_, was publish't
_Numb_. 19. _p_. 349. The _Figure_ of that _Constellation_, with the _New
Star_ in it, was thus, hastily drawn, sent over by that Observer.

[Illustration]

{373}

       *       *       *       *       *

_An Extract of a Letter written _Decemb. 28. 1666_. by M. _Auzout_ to the
Publisher, concerning a way of his, for taking the _Diameters_ of the
_Planets_, and for knowing the _Parallax_ of the _Moon_; as also the
Reason, why in the _Solar Eclipse_ above calculated, the _Diameter_ of the
_Moon_ did increase about the end._

I did apply my self the last Summer to the taking of the _Diameters_ of the
Sun, Moon, and the other Planets, by a Method, which one M. _Picard_ and my
self have, esteem'd by Us the best of all those, that have been practis'd
hitherto; since we can take the _Diameters_ to _Second Minutes_, being able
to divide one foot into 24000. or 30000. parts, scarce failing as much as
in one only part, so as we can in a manner be _assur'd_, not to deceive our
selves in 3. or 4. _seconds_. I shall not now tell you my Observations, but
I may very well assure you, that the _Diameter_ of the _Sun_ has not been
much less in his _Apogee_, than 31. m. 37. or 40. sec. and certainly not
lesse than 31. m. 35. sec. and that at present in his _Perigee_ it passes
not 32. m. 45. sec. and may be lesse by a second or two. That, which is at
the present troublesome, is, that the _Vertical_ Diameter, which is the
most easie to take, is diminisht, even at _Noon_, by 8. or 9. sec., because
of the _Refractions_, which are much greater in Winter than Summer at the
same height; and that the _Horizontal_ Diameter is difficult, because of
the swift motion of the Heavens.

As for the _Moon_, I never yet found her Diameter less than 29. m. 44. or
45. sec. and I have not seen it pass 33. m. or if it hath, it was only by a
few _seconds_. But I have not yet taken her in all the kinds of situations
of the _Apogees_ and _Perigees_ which happen, with the _Conjunctions_ and
_Quadratures_. I do not mention all, what can be deduced from thence, but
if you have Persons at _London_, that observe these _Diameters_, we may
entertain our selves more about this Subject, another time. I shall only
tell you, that I have found a Way to know the _Parallax_ of the _Moon_, by
the means of her _Diameter_: _Vid_. If on a day, when she is to be in her
_Apogee_ or _Perigee_, and in the most _Boreal_ Signes, you take her
Diameter towards the _Horizon_, and then towards the _South_, with her
_Altitudes_ {374} above the Horizon. For, if the Observation of the
Diameters be exact; as in these Situations the Moon changes not
considerably her Distance from the Earth in 6. or 7. hours, the
_Difference_ of the Diameters will shew the Proportion there is of her
Distance, with the Semi-diameter of the Earth. I do not enlarge, because
that as soon as one hath this _Idea_, the rest is easie. The same would yet
be practis'd better in the places, where the Moon passes through the
_Zenith_, than here, for the greater the difference is of the Heights, the
greater is that of the Diameters. I do not note (for it easily appears)
that, if one were under the same _Meridian_, or the same _Azimuth_ in two
very different places, and took at the same time the Diameter of the Moon,
one would do the same thing, though this Method goes not to preciseness.

From what has been said, may be collected the reason of the Observation,
which M. _Hevelius_ made in the last _Eclipse of the Sun_, touching the
increase of the Moon's Diameter about the end. I am exceeding glad, that a
person, who probably knew not the cause of it, has made the Experiment: but
it is strange, that until now no Astronomer has foreseen, that that should
happen, nor given any precepts for the Change of the _Moons Diameter_ in
the _Eclipses of the Sun_, according to the places, where they should
happen, and according to the Hour and Height, the Moon should have. For,
what hapned in that _Eclipse_ of Augmentation, would have faln out
contrarily, if it had been in the Evening; for, the Moon, which in that
_Eclipse_, that began in the Morning, was higher about the end than at the
beginning, was nearer us, and consequently was to appear bigger: But if the
_Eclipse_ should happen in the Evening, she would be lower at the end, and
therefore more distant from us, and consequently appear lesser. So also in
two different places, whereof one should have the Eclipse in the Morning,
and the other at Noon, the Moon should appear bigger to him that hath it at
Noon: And she must likewise appear bigger to those, who shall have a leser
_Elevation_ of the _Pole_ under the same _Meridian_, because the Moon will
be nearer them.

I wish, I could satisfie you about the _Optick Glasses_ of Signior
_Burattini_ in _Poland_, which he hath sent hither; but I have not yet seen
their performances my self. I only saw once the Glasses, {375} which are
perfectly well wrought and well polisht. Those, that have tried them, find
them very good; but they are only, the one of 10, the other of 8. foot. A
good Astronomer told me, that they would bear a great _Aperture_ in respect
of their length.

I do not well know, what to say to yours concerning M. _Hevelius_. Mean
while, the interest of truth, and the obliging manner, he has treated me
with, engage me to answer him, in the matter of the _Comets_: I am
perswaded, I shall convince him; but since he hath taken the _Illustrious
Royal Society_ for Judge, I accept that with all my heart.

       *       *       *       *       *

_A Relation of the loss of the Way to prepare the _Bononian Stone_ for
shining._

[Sidenote: * It is hoped notwithstanding (which also a late Letter from
abroad does hint) that some or other of the _Italian_ Vertuosi at
_Florence_ have secured this Secret.]

Though several Persons have pretended to know the Art of preparing and
calcining the _Bononian_ Stone, for keeping a while the Light once imbibed;
yet there hath been indeed but one, who had the true secret of performing
it. This was an _Ecclesiastick_, who is now dead, without having left that
skill of his to any one, as Letters from _Italy_ and _France_, some while
since, did inform. There is no substance, in Nature, known to us, that hath
the effect of this Stone; so that (to the shame of the present Age) this
_Phænomenon_ is not like to be found any where, but in Books, except some
happy _Genius_ light upon same or the like skill. *

       *       *       *       *       *

_A Description of a _Swedish_ Stone, which affords _Sulphur_, _Vitriol_,
_Allum_ and _Minium_._

This was communicated to the _R. Society_ by Sir _Gilbert Talbot_ Knight, a
Worthy Member of that Body, as he had received it in _Denmark_, being his
Majesties Extraordinary Envoy there; as follows,

[Illustration]

There is a Stone in _Sweden_ of a Yellow Colour, intermixed with streaks of
white (as if composed of Gold and Silver) and heavy withal. It is found in
firm Rocks, and runs in Veins, {376} upon which they lay Wood, and set it
on fire. When the Stone is thus heated, they cast Water upon it, to make it
rend, and then dig it up with Mattocks. This done, they break it into
smaller pieces; and put it into Iron-pots, of the shape represented by
_Figure_ C; the mouth of the one going into the other. These they place,
the _one_ in the Oven upon an Iron fork sloping, so that, the Stone being
melted, it may run into the _other_, which stands at the mouth of the Oven,
supported upon an Iron. The first running of the Stone is _Sulphur_.

The remainder of the burned Stone is carry'd out, and laid upon a high
Hill, where it lies exposed to the Sun and Air for the space of two years,
and then taketh fire of it self, casting forth a thin blew flame, scarce
discernable in the day time. This being consumed, leaveth a blew dust
behind it; which the Workmen observe, and mark with woodden pins. This they
dig up, and carry into the Work-house, and put it into great Tubs of Water,
where it infuseth 24. hours or more. The Water they afterward boyl in
Kettles, as we do Saltpeter, and put it into cooling Tubs, wherein they
place crosse Sticks, and on them the _Vitriol_ fastens, as Sugar-candy
doth.

The Water, that remains after the extraction of the _Vitriol_, they mix
with an eight part of Urin and the Lees of Wood-ashes, which is again
boyled very strong, and being set to cool in Tubbs, crosse Sticks are
likewise placed, and thereon the _Allum_ fastens.

In the Water, which remains after the _Allum_, is found a Sediment, which
being separated from the Water, is put into an Oven, and Wood laid upon it
and fired, till it become red, which makes the _Minium_, wherewith they
paint their Houses, and make plaister.

_So far this Description_; Which gave occasion to a curious person to call
to mind, That there was a kind of Stone in the _North_ of _England_,
yielding the same substances, except _Minium_. {377}

       *       *       *       *       *

_A Relation of the Raining of _Ashes_, in the _Archipelago_, upon the
Eruption of Mount _Vesuvius_, some years ago._

This came but lately to hand from that knowing person, Mr. _Henry
Robinson_, and was thought fit to be now inserted here, that it might not
be lost, though it hath hapned above 30 years ago. It was contained in a
Letter, (subscribed by Capt. _Will. Badily_) in these words:

[Sidenote: * Some of these Ashes were produced by Mr. _John Evelyn_, before
the _Royal Society_.]

The 6^{th.} of _December_ 1631, being in the Gulf of _Volo_, riding at
Anchor, about ten of the Clock that Night, it began to rain Sand or Ashes,
and continued till two of the Clock the next Morning. It was about two
inches thick on the Deck, so that we cast it over board with Shovels, as we
did Snow the day before: The quantity of a Bushel we brought home, and
presented to several Friends *, especially to the Masters of _Trinity
House_. There was in our Company, Capt. _John Wilds_ Commander of the
_Dragon_, and Capt. _Anthony Watts_, Commander of the _Elisabeth_ and
_Dorcas_. There was no Wind stirring, when these Ashes fell, it did not
fall onely in the places, where we were, but likewise in other parts, as
Ships were coming from St. _John D'Acre_ to our Port; they being at that
time a hundred Leagues from us. We compared the Ashes together, and found
them both one. If you desire to see the Ashes, let me know.

       *       *       *       *       *

_An Extract Of A Letter not long since written from _Rome_, rectifying the
Relation of _Salamanders_ living in Fire._

This came from that Expert Anatomist M. _Steno_, to Dr. _Croone Videl_.
That a Knight called _Corvini_, had assured him, that, having cast a
_Salamander_, brought him out of the _Indies_, into the Fire, the Animal
thereupon swell'd presently, and then vomited store of thick slimy matter,
which did put out the neighbouring Coals, to which the _Salamander_ retired
immediately, putting them out again in the same manner, as soon as they
{378} rekindled, and by this means saving himself from the force of the
Fire, for the space of two hours, the Gentleman above-mentioned being then
unwilling to hazard the Creature any further: That afterwards it lived nine
Months: That he had kept it eleven Months without any other food, but what
it took by licking the Earth, on which it moved, and on which it had been
brought out of the _Indies_; which at first was covered with a thick
moisture, but being dried afterwards, the Urin of the Animal served to
moisten the same. After the eleven Months, the Owner having a mind to try,
how the Animal would do upon _Italian_ Earth, it died three dayes after it
had changed the Earth.

       *       *       *       *       *

_An Account of several Engagements for Observing of Tydes._

Since nothing is more important for discovering the Cause of that Grand
_Phænomenon_ of Nature, the _Flux_ and _Reflux of the Sea_, than a true and
full _History of the Tydes_; the _Virtuosi_ of _England_ have of late
(especially since the Publication of Dr. _Wallis_ his _Theory_ touching
that _Apparence_) taken care, to direct and recommend in several parts of
the World, and particularly in the most proper places of these _Ilands_,
such Observations, as may contribute to the elucidating of that Subject.

And as formerly they have sent their _Inquiries_ of this Nature to the Isle
of St. _Helena_, situated in the open Ocean beyond the _Æquinoctial_, and
already received some account thereupon; so they have since dispatcht the
like for the _Bermudas_, an _Isle_ that hath no less conveniency of
situation for that purpose. And they intend (as will more amply appear, God
permitting, in a short time) to lodge with such Masters of Ships and
Pilots, as shall sayl into remote parts, very particular directions of that
kind, to be printed at the _Royal Societies_ charges, and to be committed
to the care of the Masters of _Trinity House_ for disposing of them to that
end.

And, as for the Observations, to be made in these Kingdoms; 'tis hoped,
that the Masters in the Art of Navigation at _Bristol_ (Mr. _Standridge_
and Mr. _Iff_) will undertake that business with affection and care: the
former of these two having already (as we are informed from a good hand)
made a Collection of the Tydes; {379} for some years past, and found them
differing from former Observations and Tables; the other promising future
diligence in this matter; noting in the mean time, that some Tydes of last
Autumn were so far differing from former Observations, that neither he, nor
any others there, could make any thing of it.

We must not omit here to mention the readiness, expressed by these worthy
Gentlemen, Mr. _Rob. Boyle_, Sir _Rob. Moray_, and Mr. _Henry Powle_, for
concurring in this Work; the first, having undertaken to recommend
Observations of this nature, to be made, upon the _Western_ Coast of
_Ireland_ *; the second, upon the West of _Scotland_; and the third, in the
Isle of _Lundy_; to whom we must adde the inquisitive Mr. _Sam.
Colepresse_, for _Plymouth_, and the _Lands-end_. Besides, we hope to
engage the curious of _France_ in the same undertaking, especially for
procuring, besides what is known already concerning that place, a very
particular and exact account of the Tydes upon the Coast of _Britany_,
where (especially about St. _Malo_) they are found to rise to admiration,
even to 60, 70, and sometime 80, feet, at the New and Full Moon.

    * The Observations particularly recommended for that Coast, are these;

    1. At what hour it is High-water on the day of the New and Full Moon,
    upon every Cape and Bay of the Western Coast of _Ireland_.

    2. How long after the New and Full Moon the highest Spring-tides fall
    out.

    3. What are the perpendicular heights of the Flood, both at the
    ordinary, and the Spring-tydes.

       *       *       *       *       *

_Some Suggestions for Remedies against _Cold_._

As there have been Remedies found out against excessive _Heat_, and Means
of cooling Meat and Drink; so it was lately, on the occasion of the sharp
Season, suggested, That Remedies might be thought on against _Cold_; and
that particularly it might be inquired into,

1. What things in Nature, or by Art, or Mechanical contrivance will retain
a warming Heat longest, or a melting or scorching Heat?

2. What will continue or maintain Fire longest?

Some that observe common practises and vulgar Trades, take notice, That
_Joyners_ use _Leaden-Pots_ for their Glue, alledging for a Reason, That
Lead, being a close Mettal, retains the heat {380} longer than other
Mettals. _Cary_'s Warming-stone promised a warmth for six or eight hours;
if it performed but for two or three hours, it would be of great use. 'Tis
found by sad experience, how hurtful Bright Fires, and especially of
Stone-coal are to the Eyes.

To retain Fire long, certain _Black_ Earths are useful, as we were newly
informed by the Inquisitive Dr. _B._ That a Gentleman in _Sommertsetshire_,
called Mr. _Speke_, had bountifully obliged _Ilminster_, and his
Neighborhood, by a Black Fat-Earth lately found in his Park. But the same
Correspondent adds, That he never saw any parallel to a _Sea-weed_, which
he and some of his Fellow-Students had in _Cambridge_ in the mouth of a
Barrel of good Oysters. It was smaller than Pease-halm, yet cut, it lasted
two very great Fires of Sea-coal, burning bright in the midst of the Fire;
and by a stroak of the Tongues, it fell into the Hearth, jingling like
Mettal.

       *       *       *       *       *

_A Relation of an uncommon Accident in two Aged Persons._

This was imparted by the above-mentioned Mr. _Colepresse_, who assures in
his Letter, containing this Account, That the matter of fact was thorowly
examined by himself, and that he was fully, and in all respects, satisfied
of the truth thereof.



_The Relation of the one, is in these words._

_Joseh Shute_ Clerk, Parson of _Mary_ (nigh _Plymouth_) in the County of
_Devon_, aged 81 years, being a temperate man, and of an healthy
constitution, having the in-most Grinder loose, and so remaining,
perceived, that his mouth, about three Moneths since, was somewhat
streightned; and upon inquiry into the cause of it, found, That he had a
new Tooth (the third Grinder) being the innermost of the upper Jaw in the
Right Cheek, which still remains firm.



_The Account of the other follows thus._

_Maria Stert_ of _Benecliffe_, in _Plympton St. Mary_ (near _Plymouth_) in
_Devon_, aged about 75 years, an healthy person, having had nine children,
about the fortieth year of her age lost three of her {381} upper
_Incisores_ or _Cutters_, the other drawn out, and so remained Toothless,
as to them, for about 25 years, when she perceived, that a new Tooth came
forth (without any pain) next the _Canini_ of the left Cheek: And about two
years after, another Tooth grew out likewise without pain, close by the
former. The first whereof, never came to above half the length of her
former _Cutters_, the latter scarce breaking the skin: Both which yet
proved serviceable, till about six weeks since, when she eating (no hard,
crusty, or solid) Meat, that Tooth which came out first, fell down into her
Mouth, without any loosness before hand perceived, or any pain; which had
not a phang like other _Cutters_, but much less, and shorter. The other
abides firm, and serviceable.

To the truth of these Relations, not onely the said _Joseph Shute_ and
_Maria Stert_, have put the one his name, the other her Mark, the third and
seventh of _January_, 1666. but also Sir _William Strode_, and Mr.
_Colepresse_ have subscribed the same, as believing the Relation to be
true.

       *       *       *       *       *

_An Account of two Books._

__I. ISMAELIS BULLIALDI_ ad Astronomos Monita duo: Primum, De Stella Nova,
quæ in Collo Ceti ante annos aliquot visa est. Alterum, De Nebulosa in
Andromeda Cinguli parte Borea, ante biennium iterum orta._

The chief end of the _Author_ in publishing this Tract, seems to be, To
excite Astronomers to a diligent observation, both of that _New Star_ in
the _Neck_ of the _Whale_, to be seen in _February_ and _March_ next; and
of that other, in the Northern part of _Andromeda's Girdle_, to be seen at
this very present.

As to the _former_ of these Stars, _he affirms_, that, as it hath appeared
for many years in the said place, so it will in the beginning of _March_
next appear equal to the Stars of the _third Magnitude_, or perhaps bigger;
and that about the end of the same Month, if the Crepuscle do not hinder,
the greatest _Phasis_ of it will appear, if so be, that it keep the same
Analogy of Motions and Periods, which it observed from _An._ 1638. to _An._
1664. Where he takes notice of the Causes, why its two greatest Appearances
could not be seen, _An._ 1664, 1665, 1666; and how he {382} comes to know,
that in the beginning of _March_ next, It will equal, or even exceed the
Stars of the _Third Magnitude_; noting, that from the Observations hitherto
made of this Star, it is manifest, that the _greatest Phases_ thereof do
every year anticipate by 32. or 33. dayes; forasmuch as _An._ 1660. its
_greatest Appearance_ was about the end of _October_ and the beginning of
_November_; _An._ 1661. about the end of _September_, or the beginning of
_October_; _An._ 1662. about the end of _August_, &c. so that this year it
must be in _March_, if the former Analogy do hold.

He collects also from the Observations, That one _Period_ from the
_greatest Phasis_ to the next, consists of about 333. dayes: but that the
interval of the time betwixt the times of its beginning to appear equal to
the Stars of the _Sixt Magnitude_, and of its ending to do so, consists of
about 120. dayes: And that its _greatest Appearance_ lasts about 15. dayes:
All which yet he would have understood with some latitude.

This done, he proceeds to the investigation of the Causes of the
Vicissitudes in the Emersion and Dis-appearance of this Star, and having
discoursed, That the apparent Increase and Decrement of every Lucid Body
proceeds _either_ from its changed distance from the Eye of the Observer;
_or_ from its various site and position in respect of him, whereby the
angle of Vision is changed; or from the increase or diminution of the bulk
of the lucid body it self: and having also demonstrated it impossible, that
this Star should move in a _Circle_, or in an _Ellipsis_; and proved it
improbable that it should move in a _Strait Line_, he concludes, that there
can be no other genuin, or at least, no other more probable cause of its
Emersion and Occultation, than this, That the bigger part of that round
Body is obscure and inconspicuous to us, and its lesser part lucid, the
whole Body turning about its own Center, and one Axe; whereby for one
determinate space of time it exhibits its lucid part to the Earth, for
another, subducts it: it not being likely, that fires should be kindled in
the Body of that Star, and that the matter thereof should at certain times
take fire and shine, at other times be extinguisht upon the consumption of
that matter.

_So far of that Star._ As to the other in the _Girdle_ of _Andromeda_, seen
about the beginning of _An._ 1665; he relates, that, when in the end of
1664. the World beheld the then appearing _Comet_, {383} Astronomers
observed also this new _Phænomenon_, which was called by them _Nebulosa in
Cingulo Andromedæ_. Concerning which, he notes, that the same had been
already seen many years before by _Simon Narius_, vid. _An._ 1612. when
with a _Telescope_ he search'd for the _Satellits_ of _Jupiter_, and
observed their motions; alledging for proof hereof, the said _Authors_ own
words, out of his own Book, _De Mundo Joviali_, publisht _An._ 1614. And
farther shews, that it hath formerly appear'd (about 150. years ago) and
been taken notice off by an expert, though Anonymous, Astronomer; whose
words he cites out of a _Manuscript_, brought out of _Holland_ by the
Excellent _Jacobus Augustus Thuanus_, returning from his Embassy to
_Paris_; wherein also was marked the _Figure_ of that _Phænomenon_;
represented in print by our Author: who from all this collects, that,
whereas this Star hath been seen formerly, and that 150. years since, but
yet neither observed by _Hipparchus_, nor any other of the Antients, that
we can find; nor also in the former Age by _Tycho Brahe_, nor in our Age,
by _Bayerus_; and appear'd also in the Month of _November_ last (wherein he
wrote this _Tract_) much lessened and obscure, after it had, two years ago,
shone very bright; that therefore it must needs appear and dis-appear by
turns, like those in the _Necks_ of the _Whale_ and _Swan_.



__II._ ENTRIENS sur les Vies et sur les Ouvrages_ Des plus excellens
Peintres, Anciens et Modernes, par Monsieur_ FELIBIEN._

This Author, having first discoursed of that Royal Pallace the _Louvre_,
and the Designs of finishing it; passes on to the Art of _Picturing_, and
treats of the three principal things, wherein a good Master of the Art must
excel, _vid._ the Composition, Designing, and Laying on of Colours, which
done, he ravels into the Origine, and deduces the Progress of Painting, and
relates what is most remarkable in the Lives of the Antient Painters: And
among many particulars, he observes in the Life of _Andreas de Sarte_, how
difficult it is, to judge well of a Picture; relating, that a Duke of
_Mantua_, having obtained of _Clement_ VII. a Pourtrait of _Leo_ X. which
had been done by _Raphael Urbin_, and was at _Florence_, those of that Town
being unwilling to lose so excellent a {384} piece, caused a Copy thereof
to be made by the said _Andreas de Sarte_, which they sent instead of the
Original. This _Copy_ was so perfect, that _Julio Romano_, who had been
bred and taught by _Raphael_, and was one of the best Painters of _Italy_,
took it for an _Original_; and would never have been undeceived, if one
_Vasari_ had not assured him, that it was but a Copy, which himself had
seen made, and had not shew'd him certain marks, that were there put to
discriminate it from the Original.

In the _Second_ Part, the Author has set down all that is requisite to
judge and discourse well of Painting. But, to add Examples to Precepts, he
discourses of the _Modern_ Painters, and making a Description of their best
Works, he takes occasion to observe, what is there found most excellent,
and to shew, how they have put in practice the Rules of Art. He treats also
of the declining of Painting, and affirms, that nothing considerable hath
been done in it from the time of _Constantine_, till _An._ 1240. when one,
_Cimabue_, began to raise this Art again. After this, he give a List of the
Painters, that since have been famous for their Works, preferring before
all others, _Raphael Urbin_. The last of all is the above-mention'd _Andrè
de Sartes_, who died, _An._ 1530. and whom the liberality of _Francis_ I.
had drawn into _France_.

       *       *       *       *       *


The Printing of these Tracts is now return'd to the first Printer thereof,
as being somewhat re-setled after the late sad Fire of _London_.

_FINIS._

       *       *       *       *       *


In the _SAVOY_, Printed by _T. N._ for _John Martyn_, Printer to the _Royal
Society_, and are to be sold at his Shop a little without Temple-Bar, 1667.

{385}

       *       *       *       *       *




_Numb._ 22.

PHILOSOPHICAL
_TRANSACTIONS._

       *       *       *       *       *

_Monday_, _February_ 11. 1666.

       *       *       *       *       *

The Contents.

    _Trials proposed to be made for the Improvement of the Experiment of
    _Transfusing Blood out of one live Animal into another_. A Method for
    _Observing the Eclipses of the Moon_, free from the Common
    Inconveniences. An Account of some Celestial Observations lately made
    at _Madrid_. Extract of a Letter, lately written to the Publisher,
    containing some observations about _Insects_ and their Inoxiousness,
    &c. An Account of some Books, _vid._ _I. TOME TROISIEME DES LETTRES DE
    M. DESCARTES. II. ASTRONOMIA REFORMATA P. RICCIOLI. III. ANATOME
    MEDULLÆ SPINALIS ET NERVORUM_, inde provenientium, _GERARDI BLASII_,
    M.D. An Advertisement about the re-printing of M. _Evelyns_ Sylva and
    Pomona. A _Table_ of the _Transactions_, printed these two years._

       *       *       *       *       *

_Tryals proposed by Mr. _Boyle_ to Dr. _Lower_, to be made by him, for the
Improvement of Tranfusing blood out of one live Animal into another;
promised _Numb. 20. p. 357_._

The following _Queries_ and _Tryals_ were written long since, and read
about a Moneth ago in the _R Society_, and do now come forth against the
Authors intention, at the earnest desire of some Learned Persons, and
particualrly of the worthy _Doctor_, to whom they were addressed; who
thinks, they may excite and assist others in a matter, which, to be well
prosecuted, will require many hands. At the reading of them, the _Author_
declared, that of divers of them he thought he could fore-see the Events,
but {386} yet judged it fit, not to omit them, because the Importance of
the _Theories_, they may give light to, may make the Tryals recompence the
pains, whether the success favour the _Affirmative_ or the _Negative_ of
the Question, by enabling us to determine the one or the other upon surer
grounds, than we could otherwise do. And this Advertisement he desires may
be applied to those other Papers of his, that consist of _Quæries_ or
proposed _Tryals_.

_The _Quæries_ themselves follow._

1. Whether by this way of Transfusing Blood; the disposition of Individual
Animals of the same kind, may not be much altered? (As whether a _fierce_
Dog, by being often quite new stocked with the blood of a _cowardly_ Dog,
may not become more tame; _& vice versa, &c_?)

2. Whether immediately upon the unbinding of a Dog, replenisht with
adventitious blood, he will know and fawn upon his Master; and do the like
customary things as before? And whether he will do such things better or
worse at some time after the Operation?

3. Whether those Dogs, that have _Peculiarities_, will have them either
abolisht, or at least much impaired by transfusion of blood? (As whether
the blood of a _Mastiff_, being frequently transfused into a _Blood-hound_,
or a _Spaniel_, will not prejudice them in point of scent?)

4. Whether acquired Habits will be destroy'd or impair'd by this
Experiment? (As whether a Dog, taught to fetch and carry, or to dive after
Ducks, or to sett, will after frequent and full recruits of the blood of
Dogs unfit for those Exercises, be as good at them, as before?)

5. Whether any considerable change is to be observ'd in the Pulse, Urin,
and other Excrements of the _Recipient_ Animal, by this Operation, or the
quantity of his insensible Transpiration?

6. Whether the _Emittent_ Dog, being full fed at such a distance of time
before the Operation, that the mass of blood may be suppos'd to abound with
_Chyle_, the _Recipient_ Dog, being before hungry, will lose his appetite,
more than if the _Emittent_ Dogs blood had not been so chylous? And how
long, upon a {387} Vein opened of a Dog, the admitted blood will be found
to retain _Chyle_?

7. Whether a Dog may be kept alive without eating by the frequent Injection
of the Chyle of another, taken freshly from the Receptacle, into the Veins
of the _Recipient_ Dog?

8. Whether a Dog, that is _sick_ of some disease chiefly imputable to the
mass of blood, may be cured by exchanging it for that of a _sound_ Dog? And
whether a _sound_ Dog may receive such diseases from the blood of a _sick_
one, as are not otherwise of an infectious nature?

9. What will be the Operation of frequently stocking (which is feasible
enough) an _old_ and feeble Dog with the blood of _young_ ones, as to
liveliness, dulness, drowsiness, squeamishness, &c., _et vice versa_?

10. Whether a _small_ young Dog, by being often fresh stockt with the blood
of a young Dog of a _larger_ kind, will grow bigger, than the ordinary size
of his own kind?

11. Whether any Medicated Liquors may be injected together with the blood
into the _Recipient_ Dog? And in case they may, whether there will be any
considerable difference found between the separations made on this
occasion, and those, which would be made, in case such Medicated Liquors
had been injected with some other Vehicle, or alone, or taken in at the
mouth?

12. Whether a Purging Medicine, being given to the _Emittent_ Dog a while
before the Operation, the _Recipient_ Dog will be thereby purged, and how?
(which Experiment may be hugely varied.)

13. Whether the Operation may be successfully practis'd, in case the
injected blood be that of an Animal of another _Species_, as of a _Calf_
into a _Dog_, &c. and of a _Cold_ Animal, as of a _Fish_, or _Frog_, or
_Tortoise_, into the Vessels of a _Hot_ Animal, and _vice versa_?

14. Whether the _Colour_ of the Hair or Feathers of the _Recipient_ Animal,
by the frequent repeating of this Operation, will be changed into that of
the _Emittent_?

15. Whether by frequently transfusing into the same Dog, the blood of some
Animal of another _Species_, something further, and more tending to some
degrees of a change of _Species_, may {388} be effected, at least in
Animals near of Kin; (As Spaniels and Setting Dogs, Irish Grey-hounds and
ordinary Grey-hounds, &c?)

16. Whether the Transfusion may be practic'd upon pregnant Bitches, at
least at certain times of their gravidation? And what effect it will have
upon the Whelps?

_There_ were some other _Quæries_ proposed by the same _Author_; as, the
weighing of the _Emittent_ Animal before the Operation, that (making an
abatement for the Effluviums, and for the Excrements, if it voids any) it
may appear, how much blood it really loses. To which were annext divers
others not so fit to be perused but by _Physitians_, and therefore here
omitted.

       *       *       *       *       *

_A Method for Observing the _Eclipses of the Moon_, free from the Common
Inconveniencies, as it was left by the Learned Mr. _Rook_, late
_Gresham_-Professor of Geometry._

Eclipses of the Moon are observed for two principal ends; One
_Astronomical_, that by comparing Observations with Calculations, the
_Theory_ of the _Moons Motion_ may be perfected, and the _Tables_ thereof
reformed: the other, _Geographical_, that by comparing among themselves the
Observations of the same _Ecliptick Phases_, made in _divers_ places, the
_Difference_ of _Meridians_ or _Longitudes_ of those places may be
discerned.

The Knowledge of the Eclipse's Quantity and Duration, the Shadows, Curvity,
and Inclination, &c. conduce only to the former of these ends. The exact
time of the Beginning, Middle, and End of Eclipses, as also in _Total_
ones, the Beginning and End of _Total_ darkness, is useful for both of
them.

But because in Observations made by the _bare_ Eye, these times
considerably differ from those with a _Telescope_; and, because the
_Beginning_ of Eclipses, and the _End_ of _Total_ darkness, are scarce to
be observed exactly, even with Glasses (none being able clearly to
distinguish between the _True_ Shadow and _Penumbra_, unless he hath seen,
for some time before, the Line, separating them, pass along upon the
Surface of the Moon;) and lastly, because in small {389} _Partial_
Eclipses, the Beginning and End, and in _Total_ ones of short continuance
in the Shadow, the Beginning and End of _Total_ darkness, are unfit for
nice Observations, by reason of the slow change of _Apparences_, which the
_Oblique_ Motion of the Shadow then causeth. For these reasons I shall
propound a _Method_ peculiarly design'd for the Accomplishment of the
_Geographical_ end in Observing Lunar Eclipses, free (as far as is
possible) from all the mentioned Inconveniences.

For, _First_, It shall not be practicable without a Telescope. _Secondly_,
The Observer shall alwayes have opportunity before his principal
Observation, to note the Distinction between the _True Shadow_ and the
_Penumbra_. And, _Thirdly_, It shall be applicable to those Seasons of the
Eclipse, when there is the suddenest Alteration in the _Apparences_.

To satisfie all which intents,

Let there be of the Eminentest _Spots_, dispersed over all Quarters of the
Moons Surface, a select number generally agreed on, to be constantly made
use of, to this purpose, in all parts of the World. As, for Example, those,
which _M. Hevelius_ calleth,

         { Sinai.
         {
         { Æthna.                   { Besbicus.           { Mæotis.
   Mons  {                  Insula. {               Palus {
         { Porphyrites.             { Creta.              { Maræotis.
         {                                          Lacus Niger Major.
         { Serorum.

Let in each _Eclipse_, not all, but (for instance) three of these _Spots_,
which then lie nearest to the _Ecliptick_, be exactly observed, when they
are first touch'd by the _True_ Shadow, and again, when they are just
compleatly entred into it, and (if you please) also in the _Decrease_ of
the Eclipse, when they are first fully clear from the _True_ Shadow: For
the accurate determinations of which moments of time (that being in this
business of main importance) let there be taken _Altitudes_ of remarkable
_Fixed Stars_ on this {390} side of the _Line_, of such, as lie between the
_Æquator_ and _Tropick_ of _Cancer_; but _beyond_ the _Line_, of such, as
are situate towards the other _Tropick_; and in all places, of such, as at
the time of Observation, are about 4. hours distant from the _Meridian_.

       *       *       *       *       *

_An Account of some Observations, lately made in _Spain_, by His Excellency
the _Earl of Sandwich_._

The Right Honourable the _Earl of Sandwich_, as he appears eminent in
discharging the Trust, his Majesty hath reposed in him, of Ambassador
Extraordinary to the King of _Spain_; so he forgets not in the midst of
that Employment, that he is a Member of the _Royal Society_; but does from
time to time, when his weighty State-Negotiations do permit, imploy himself
in making considerable Observations of divers kinds, both _Astronomical_
and _Physiological_; and communicateth the same to the said _Society_; as
for instance, lately, what he has observ'd concerning the _Solar Eclipse_
in _June_ last, the Suns height in the Solstice, and also the Latitude of
_Madrid_, esteeming by the Suns Altitude in the _Solstice_, and by other
Meridian Altitudes, the _Latitude_ of _Madrid_ to be 40 deg. 10 min; which
differs considerably from that assigned by others; the General Chart of
_Europe_ giving to it 41 deg. 30 min. the General Map of _Spain_, 40 deg.
27 min. A large Provincial Map of _Castile_, 40 deg. 38 min.

To these particulars, and others formerly imparted, his Excellency is
making more of the same nature; and particularly those of the Immersion of
the _Satellites_ of _Jupiter_.

We must not omit mentioning here, what he hath observed of _Halo_'s about
the _Moon_; which he relates in these words;

_Decemb._ 25. _Old Style_, 1666. In the Evening, here (vid. at _Madrid_)
was a great _Halo_ about the Moon, the _Semidiameter_ whereof was about 23
deg. 30 min. _Aldebaran_ was just in the _North-east_ part of the _Circle_,
and the two Horns of _Aries_ just enclosed by the _South-west_ of the
_Circle_, the Moon being in the _Center_. I note this the rather (_saith
he_) because five or six years ago, vid. _Novemb._ 21. _Old Style_, 1661.
an hour after Sun-set, I saw a great _Halo_ about the Moon of the same
_Semidiameter_, {391} at _Tangier_, the Moon being very near the same
place, where she was now.

       *       *       *       *       *

_Extract of a Letter, lately written by Mr. _Nathaniel Fairfax_ to the
_Publisher_, containing Observations about some _Insects_, and their
Inoxiousness, &c._

The Ingenious Author of this Letter, as he expresses an extraordinary
desire to see the _Store-house_ of _Natural Philosophy_, more richly
fraughted (a Work begun by the single care and conduct of the Excellent
Lord _Verulam_, and prosecuted by the Joynt-undertakings of the _R.
Society_) so he very frankly offers his Service in contributing some of his
Observations, and begins in this very Letter to perform his Offer. For,
Having taken notice of what was publisht in _Numb. 9. p. 161_. out of the
_Italian_ Philosopher _Redi_, vid. That Creatures, reputed Venomous, are
indeed no Poysons, when swallow'd, though they may prove so, when put into
Wounds: He, for confirmation thereof, alledges Examples of several Persons
well known to him (himself also having been an Eye-witness to some such
Experiments) who have frequently swallow'd _Spiders_, even of the rankest
kind, without any more harm than happens to Hens, Robin-red-breasts, and
other Birds, who make Spiders their daily Commons. And having made mention
of some men, that eat even _Toads_, he adds, that though a Toad be not a
Poyson to us in the whole; yet it may invenome outwardly, according to some
parts so and so stirr'd; an instance whereof he alledges in a Boy, who
stumbling on a Toad, and hurling stones at it, some Juyce from the bruised
Toad chanced to light upon his Lips, whereupon they swell'd, each to the
thickness of about two Thumbs: And he neglecting to use, what might be
proper to restore them, they have continued in that mishapen size ever
since; the ugliness whereof, when the Relator saw, gave him occasion to
inquire after the cause of it, which thereupon he understood to be, as has
been recited.

On this occasion, the same Gentleman relates, that once seeing a Spider
bruised into a small Glass of Water, and that it tinged {392} it somewhat
of a Sky-colour, he was, upon owning his surprise thereat, informed, that a
dozen of them being put in, they would dye it to almost a full _Azure_.
Which is touch't here, that, the Experiment being so easie to make, it may
be tried, when the season furnishes those Insects; meantime, it seems not
more incredible, that this Creature should yield a Sky-colour, when put in
water, than that _Cochineel_, which also is but an Insect, should afford a
fine _red_, when steep'd in the same Liquor.

       *       *       *       *       *

_An Account Of Some Books._

_I._ Le Tome troisieme et dernier des Lettres de _M. DES-CARTES_.

As the two first _Tomes_ of M. _Des-Cartes_ his Letters, contain Questions,
for the most part of a _Moral_ and _Physiological_ Nature, proposed to, and
answer'd by him; so _this_ consists of the Contests, he had upon several
Subjects with divers Men eminent in his time.

To pass by that sharp Contest, he was engaged in by some Professors of
Divinity at _Utrecht_, who endeavoured to discredit his Philosophy, as
leading to Libertinisme and Atheisme, notwithstanding he made it so much
his business, as to assert the Existence of a Deity, and the Immortality of
a Soul: We shall take notice of what is more to our purpose, _vid._ the
Differences, he had touching his _Dioptricks_ and _Geometry_.

As for his _Dioptricks_, though a great part of the Learned World have much
esteem'd that Treatise, as leaving little to be said after him upon that
Subject; yet there have not been wanting Mathematicians, who have declared
their disagreement from his Principles in that Doctrine. The first of them
was the Jesuit _Bourdin_, Mathematick Professor in the Colledg of
_Clermont_ at _Paris_; but this difference was soon at an end. A second was
Mr. _Hobbs_, upon whose account he wrote several Letters to _Mersennus_,
containing many remarks conducing to the Knowledge of the Nature of
_Reflection_ and _Refraction_. But the Person, that did most learnedly and
resolutely attack the said _Dioptricks_, was Monsieur _Fermat_, {393}
writing first about it to _Mersennus_, who soon communicated his Objections
to M. _Des-Cartes_, who failed not to return his Answer to them. But
_Fermat_ replied, and _Des-Cartes_ likewise; and after many reciprocations,
in which each party pretended to have the advantage, the matter rested;
until M. _Fermat_ taking occasion to write afresh of it to M. _De la
Chambre_, several years after _Des-Cartes_'s death, upon occasion of a
Book, written M. _De la Chambre_, _Of Light_; discoursed with this new
_Author_ after the same rate, as he had done before with _Des-Cartes_
himself, and seemed to invite some-body of his friends, to re-assume the
former contest. Whereupon M. _Clerselier_ and M. _Rohault_ took up the
Gantlet, to assert the Doctrine of the deceased Philosopher, exchanging
several Letters with M. _Fermat_, all inserted in this _Tome_, and serving
fully to instruct the Reader of this Difference, and withal to elucidate
many difficult points of the Subject of _Refractions_; especially of this
particular, _Whether the Motion of Light is more easily, and with more
expedition, perform'd through _dense_ Mediums, than _rare_._

Besides this, though one would think, Disputes had no place in _Geometry_,
since all proofs there, are as many Demonstrations; yet M. _Des-Cartes_
hath had several scufles touching that Science. As M. _Fermat_ had
assaulted his _Dioptricks_, so He reciprocally examined his Treatise _De
Maximis & Minimis_, pretending to have met with _Paralogismes_ in it. But
the Cause of M. _Fermat_ was learnedly pleaded for, by some of his Friends,
who took their turn to examine the Treatise of _Des-Carte_'s Geometry;
whereupon many _Letters_ were exchanged, to be found this Book, and
deserving to be considered; which doubtless the Curious would easily be
induced to do, if Copies of this Book were to be obtain'd here in
_England_, besides that one, which the _Publisher_ received from his
_Parisian_ Correspondent, and which affords him the opportunity of giving
this, though but Cursory, Account of it.

As to _Physicks_, there occur chiefly two Questions, learnedly treated of
in this _Volume_, though not without some heat between M. _Des-Cartes_ and
M. _Roberval_. The _one_ is, touching the Vibrations of Bodies suspended in
the Air, and their Center of Agitation: about which, there is also a Letter
inserted of {394} M. _Des-Cartes_ to that late Noble and Learned English
Knight, Sir _Charles Cavendish_. The _other_ is, whether Motion can be made
without supposing a _Vacuum_: where 'tis represented, That, if one
comprehend well the Nature, ascribed to the _Materia subtilis_, and how
Motions, called _Circular_, are made, which need not be just _Ovals_ or
_true_ Circles, but are only called Circular, in regard that their Motion
ends, where it had begun, whatever irregularity there be in the Middle; and
also, that all the Inequalities, that may be in the Magnitude or Figure of
the parts, may be compensated by other inequalities, met with in their
Swiftness, and by the facility, with which the parts of the _Subtle
Matter_, or of the first _Cartesian_ Element, which are found every where,
happen to be divided, or to accommodate their Figure to the Space, they are
to fill up: If these things be well understood and considered, that then no
difficulty can remain touching the Motion of the parts of Matter _in
pleno_.

Besides all these particulars, treated of in this _Tome_, there occur many
pretty Questions concerning _Numbers_, the _Cycloid_, the manner of
_Working Glasses for Telescopes_, the way of _Weighing Air_, and many other
Curiosities, Mathematical and Physical.



_II. _ASTRONOMIA REFORMATA_, Auctore _JOHANNE BAPT. RICCIOLI_, Soc. Jesu._

For the Notice of this Book, and the Account of the Chief Heads contained
therein, we are obliged to the _Journal des Scavans_; which informs us,

_First_, That the Design of this Work is, that, because several
_Astronomers_, having had their several _Hypotheses_, there is found so
great a diversity of opinions, that it is difficult thence to conclude any
thing certain; this Author judged it also necessary, to compare together
all the best Observations, and upon examination of what they have most
certain in them, to reform upon that measure the Principles of Astronomy.

_Secondly_, That this _Volume_ is divided into two Parts, whereof the
_First_ is composed of _Ten_ Books; in which the Author {395} considers the
principal Observations, hitherto made of the Motion of the Planets and the
Fixed Stars, of their Magnitude, Figure, and other Accidents; drawing
thence several Conclusions, in which he establishes his _Hypothesis_. The
_second_ contains his _Astronomical Tables_, made according to the
_Hypotheses_ of the First Part, together with Instructions teaching the
manner of using them.

_Thirdly_, That Astronomers will find in this Book many very remarkable
things, concerning the _Apparent Diameter of the Sun_ and the other Stars,
the Motion of the _Libration of the Moon_, the _Eclipses_, _Parallaxes_,
and _Refractions_: And that this Author shews, that there is a great
difference between _Optical_ and _Astronomical_ Refraction, which _Tycho_
and many others have confounded; undertaking to prove, that, whereas these
_Astronomers_ have believed, that the remoter any Star is, the less is its
Refraction, on the contrary the Refraction is the greater, the more a Star
is distant. And among many other things, he ingeniously explicates the two
contrary Motions of the Sun, from East to West, and _vice versa_, by one
onely Motion upon a _Spiral_, turning about a _Cone_.

_Fourthly_, That he represents, How uneasie it is to establish sure
Principles of this Science, by reason of the difficulties of making exact
Observations. So, for example, in the Observation of the _Equinox_, every
one is mistaken by so many _Hours_, as he is of _Minutes_, in the Elevation
of the _Pole_, or the Diameter of the Sun, or the Refraction, or in any
other circumstance. In the Observation of the _Solstice_, the error of one
only _Second_ causeth a mistake of an _Hour_ and an _half_: mean time 'tis
almost impossible to avoid the error of a _Second_; and even the sharpest
sight will not be able to perceive it, except it be assisted with an
Instrument of a prodigious bigness. For to mark _Seconds_, though Lines
were drawn as subtil as the single threds of a Silk-worms Clew, (which are
the smallest spaces to be discerned by the sharpest Eye) by the Calculation
made by this Author there would need an Instrument of 48. feet _Radius_,
since Experience shews, that there needs no more at most, than 3600. threds
of Silk to cover the space of an _inch_. But, suppose one could have a
_Quadrant_ of this bigness, who can assure himself, that dividing it into
{396} 324000. parts (for so many _Seconds_ there are in 90. _Degrees_)
either in placing it, or in observing, he shall not mistake the thickness
of a single thred of Silk? He adds, that Great Instruments have their
defects, as the small ones: For in those, that are _Movable_, if the thred,
on which the Lead hangs, is any thing big, it cannot exactly mark
_Seconds_; if it be very fine, it breaks, because of its great length, and
the weight of the Lead: And in the _Fixed_ ones, the greater the _Diameter_
is, the less the Shadow or the Light is terminated; so that it is painful
enough, exactly to discern the extremities thereof. Yet 'tis certain, that
the greater the Instruments are, the surer _Astronomers_ may be: Whence it
is, the some _Astronomers_ have made use of _Obelisks_ of a vast bigness,
to take the _Altitudes_; and Signior _Cassini_, after the example of
_Egnatio Dante_, caused a hole to be made on the highest part of a Wall of
95. feet in a Church at _Bononia_, through which the beams of the Sun
falling on the Floor, mark as exactly as is possible, the height of that
Luminary.

_Fifthly_, That the Author reasons for the _Immobility of the Earth_ after
this manner. He supposes for certain, that the swiftness of the Motion of
heavy bodies doth still _increase_ in their descent; to confirm which
principle, he affirms to have experimented, That, if you let fall a Ball
into one of the Scales of a Ballance, according to the proportion of the
height, it falls from, it raiseth different weights in the other Scale. For
example, A Wooden Ball, of 1½ ounce, falling from a height of 35 inches,
raiseth a weight of 5. ounces; from the height of 140 inches, a weight of
20 ounces; from that of 315 inches, one of 45 ounces; and from another of
560 inches, one of 80 ounces, &c. From this principle he concludes the
Earth to be at Rest; for _saith he_, if it should have a Diurnal Motion
upon its Center, Heavy Bodies being carried along with it by its motion,
would in descending describe a _Curve Line_, and, as he shews by a
_Calculus_, made by him, run equal spaces in equal times; whence it
follows, that the Celerity of their Motion would not increase in
descending, and that consequently their stroke would not be stronger, after
they had fallen thorow a longer space. {397}



_III. _ANATOME MEDULLAE SPINALIS, ET NERVORUM_ inde provenientium, _GERARDI
BLASII_, M. D._

The Author shews in this little _Tract_ a way of taking the entire _Medulla
Spinalis_, or Marrow of the Back, out of its _Theca_ or Bony Receptacle
_without Laceration_; which else happens frequently, both of the Nerves
proceeding from it, and of the Coats investing it; not to name other parts
of the same. This he affirms to have been put into practice by himself, by
a fine Saw and Wedge; which are to be dexterously used: and he produceth
accordingly in excellent Cuts, the Representations of the Structure of the
said _Medulla_ thus taken out, and the _Nerves_, thence proceeding; and
that of several Animals, Dogs, Swine, Sheep.

He intermixes several Observations, touching the _Singleness_ of this
_Medulla_, against _Lindanus_ and others; its _Original_; vid. Whether it
be the Root of the Brain, or the Brain the Root of it: its difference of
_Softness_ and _Hardness_ in several Animals; where he notes, that in
_Swine_ it is much softer than in Dogs, &c.

He exhibits also the Arteries, Nerves, and Veins, dispersed through this
_Medulla_, and inquires, Whether the _Nerves_ proceed from the _Medulla_ it
self, or its _Meninx_; and discourses also of the _Principle_ and
_Distribution_ of the Nerves; referring for ampler information in this and
the other particulars, to that Excellent Book of the Learned Dr. _Willis_,
_De Anatome Cerebri_. {398}

       *       *       *       *       *


_Advertisement._

    _It was thought fit to publish here_ the following _Advertisement_ of
    _John Evelyn_ Esquire, and that, as himself proposed it. _Viz_,

Being much solicited by many worthy Persons, to publish a _Second Edition_
of my Discourse and Directions concerning _Timber, &c._ which was printed
at the Command and by the Encouragement of the _R. Society_, I do humbly
request, that if any Person have any Material, Additions or Reformations,
which he thinks necessary either to the Part, which concerns the
Improvement of _Forrest-Trees_, or that of _Cider_, he would be pleased to
communicate his Notes and Directions to Mr. _H. Oldenburgh_, one of the
Secretaries of the said Society, at his House in the _Palmal_ of _St.
James's Fields Westminster_, with what speed they conveniently can, before
our _Lady-day_ next, to be inserted into this intended _Edition_.

       *       *       *       *       *


NOTE,

_What was observed, _Numb. 20_. p. 364, l. 18, of the Number of
_Vegetables_,_ (_vid._ That they are about 410.) _found in _England_; and
catalogued by Dr. _Merret_ in his _Pinax_, &c. is to be understood only of
the _different Kinds_ of Plants, not of the several sorts of several
Plants; for, these being comprised, the Number will amount to about 1400._

       *       *       *       *       *


{399}

THE
_PHILOSOPHICAL TRANSACTIONS_
OF
Two Years, 1665 and 1666, beginning _March_ 6. 1665.
and ending with _February_ 1666; abbreviated in an
ALPHABETICAL TABLE:
And also afterwards Digested into a more
_NATURAL METHOD_.

In the TABLE, the first _Figure_ signifies the _Number_ of the _Tracts:_
the second, the _Page_, as it is remarked in the same.

                  A.

  _Agriculture_, Head of Inquiries concerning it. _num._ 5 _pag._ 91.

  _Air._ The weight of it in all changes, by wind, weather, or whatever
      other influence observable by a standing _Mercurial Balance_, call'd
      a _Baroscope_, hinted in reference to M. _Hooks_ Micrography, n. 2.
      p. 31.
    applied to particulars by Dr _Beale_, 9. 153.
    with additions, 10. 163.
    described with observables relating to an Earth-quake about _Oxford_ by
        Dr.  _Wallis_, 10. 167.
    Mr. Boyle's remarks on the same, 11. 181.
    The _Wheel-Baroscope_ improved and delineated by M. _Hook_, 13. 218.
    Another Balance of the Air contrived by M. _Boyle_, and call'd
        _Statical_, by which the former may be exactly stated and examin'd
        for many particular applications, 14. 231.

  _Anatome_, see _Flesh_, _Blood_, _Animals_, _Lungs_, _Petrification_,
      _Taste_; item, _Steno_, _Graeff_, _Bellinus_, _Redi_, in the _Liste
      of Books_.

  _Animals_, one may live by the blood of another, the whole mass of his
      own blood being drawn out, and the blood of another infus'd in the
      mean time, 20. 353. See _Bloods Tranfusion_.
    The Generation and Functions of Animals deduced by Mechanical
        principles, without recourse to _substantial form_, 18. 325.  See
        _Honor. Fabri._ & n. 20. p. 365.  See also _Guarini_.

  _Artificial Instruments_ or _Engins._ To weigh _air_, see _Baroscope_, or
      rather _Air_.
    To discern drought or moisture of the Air, see _Hygroscope_.  n. 2. p.
        31.
    appliable in the observation of _Tydes_, 17. 300.
    _Thermometers_, to measure degrees of heat and cold, 2. 31.
    described, 10. 166.
    applied in the examination of _Tydes_, 17. 300.
    An Instrument for graduating _Thermometers_, to make them _Standards_
        of heat and cold, 2. 31.
    A new Engine for grinding any Optick Glasses of a Sphærical figure, 2.
        31.
    To measure the Refractions of Liquors of all kinds, for establishing
        the Laws of Refraction, 2. 32.
    To break the hardest Rocks in _Mines_, 5. 82.
    To try for _fresh_ waters at the bottom of the _Seas_, 9. 147.
    To find the greatest depths in the Sea, 9. 147.
    The _Engin_ for fetching up fresh water defended by Explication, 13.
        228.
    Huge _Wheels_, and other Engins for _Mines_, 2. 23.
    By the fall of water to blow wind, as with Bellows, 2. 25.
  {400}

  _Astronomical_ Remarks of a _New Star_ seen by _Hevelius_ in _Pectore
      Cygni_, which he supposeth to be the same, which _Kepler_ saw A.
      1601. and continued until 1602. and was not seen again until 1662.
      and then almost always hiding it self till 24. _Nov._ 1666. _That_,
      seen by _Kepler_ was of the third magnitude; this now, of the sixth
      or seventh. Q. Whether it changes place and magnitude, 19. 349.
    The _Scheme_, 21. 372.
    A _New Star_ in _Collo Ceti_, observ'd from 1638, to 1664, 1665, 1666.
        with its vicissitudes and periods, and causes of change, open'd by
        _Bullialdus_, who conceives the bigger part of that round body to
        be obscure, and the whole to turn about its own Center, 21. 382.
    Another _New Star_ call'd _Nebulosa_ in _Cingulo Andromedæ_, seen when
        the Comet appear'd 1665. observ'd by the said _Bullialdus_ to
        appear and disappear by turns, _ibid._ 383.
    A method for observing the _Eclipses of the Moon_, free from the common
        Inconveniences, by M. _Rook_, 22. 387.

                  B.

  _Baroscope._ See _Air_ and _Artificial_ Instruments.

  _Blood._ The new Operation of _Transfusing_ blood into the veins, out of
      one Animal into another; with considerations upon it, 20. 353.
    The first Rise of this Invention, 7. 208.
    The Success, 19. 352.
    Proposals and Queries, for the improvement of this Experiment, by M.
        _Boyle_, 22. 385, 386.

  Little Blood-letting in _China_, 14. 249.
    Blood found in some mens veins like Milk, or of the colour of Milk, 6.
        100.
    again p. 117. 118.
    and again 8. 139.

  A _Bolus_ in _Hungary_ good as _Bole Armenick_, 1. 11.

  The _Bononian Stone_, see _Light_ or _Stone_, 21. 375.

  _Books_ abbreviated, or recited:
    Laur. _Bellinus_ de Gustùs Organo novissimè deprehenso, 20. 366.
        abbrev.
    Gerh. _Blasii_ Anatome Medullæ Spinalis & Nervorum inde procedentium,
        abbrev. 22. 397.
    Mr. _Boyle_ of Thermometers and History of Cold, abbrev. 1. 8. more 3.
        46.
    ---- His _Hydrostatical Paradoxes_ abbrev. 8. 145. more largely 10.
        173.
    ---- His _Origin of Forms_ and _Qualities_, 8. 145. abbreviated 11.
        191.
    Monsieur _de Bourges_ his Relation of the Bishop of _Beryte_ his
        Voyages in _Turky_, _Persia_, _India,_ abbrev. 18. 324.
    _Bullialdi_ Monita duc, abbrev. 21. 381. See sup á _Astronomy_.
    _Des Cartes_ his Third Volume of _Letters_, 22. 392.
    _De la Chambre_'s Causes of the inundation of the Nile, abbr. 14. 251.
    _Cordemoy_ of the difference of Bodies and Souls, or Spirits, and their
        operation upon one another, abbrev. 17. 306.
    _Euclidis_ Elementa Geometrica novo ordine de nonstrata, 15. 261.
    Hon. _Fabri_ Soc. Jes. Tract. duo 1. de Plantis & Genet. Animalium. 2.
        de Homine; abbreviated, 18. 325.
    _Felibien_ of the most excellent Paintings, 21. 383.
    Catalogue of _Fermats_ Writings, and his character, 1. 15.
    _De Graeff_, de Succi Pancreatici natura & usu, abbrev. 10. 178.
    _Guarini_ Placita Philosophica, abbreviated, 20. 365.
    _Hevelius_'s Prodromus Cometicus, abbrev. 6. 104.
      His _Descriptio Cometica cum Mantissa_, abbrev. 17. 301.
    _Hobbes_ de Principiis & Ratione Geometrarum, described, 14. 193.
      Animadverted upon by Dr. _Wallis_, 16. 289.
    _Hooks_ Micrographical and Telescopical Observations, Philosophical
        Instruments and Inventions, abbr. 2. 29.
    _Kircher_'s Mundus Subterraneus, abbrev. 6. 109.
    _Lower_'s Vindication of Dr. _Willis_ de Febribus, 4. 77.
    _Meret_'s Pinax Rerum Naturalium Britannicarum, continens Vegetabilis,
        Animalia & Fossilia, in hac insula reperta, inchoatus; abbr. 20.
        364.
    _Parker_'s Tentamina Physico Theologica, abbrev. 18. 324.
    _Redi_ an Italian Philosopher, of Vipers, abbrev. 9. 160.
    _Ricciolo_'s Astronomia Reformato, Volumen quartum abbrev. 22. 394.
    _Smith_ of K. _Solomon_'s Pourtraicture of Old Age, 14. 254.
  {401}
    _Stetonis_ de Musculis & Glandulis observatium Specimen; cum duabus
        Epistolis Anatomicis, abbrev. 10. 176.
    _Sydenhami_ Methodus Curandi Febras, abbrev.  12. 210.
    _Thevenot's_ Relation of curious Voyages, with a Geographical
        description of _China_, abbr.  14. 248.
    The English _Vineyard_ vindicated, 15. 262.
    Isaac _Vossius_ de Origine Nili, abbreviated, 17. 304.
    _Vlug-Beig_ great Grand-child to the famous _Tamerlane_, his Catalogue
        of fix't Stars, with their Longitudes, Latitudes, and Magnitudes,
        taken at _Samarcand_, A. 1437. Translated out of a _Persian_ M. S.
        by M. _Hyde_, Keeper of the Bodleian Library, 8. 145.
    The _Burning_ Concave of _M. de Vilette_ in _Lyons_, burning and
        melting any matter (very few excepted.) What, and How, and at what
        distance. The proportion; and compared with other rare burning
        Concaves, 6. 96.

                  C.

  In _China_ very ancient Books found of the nature and vertues of Herbs,
      Trees and Stones, 14. 249.
    The Root _there_ called _Genseng_, very restorative and cordial,
        recovering agonizing persons, sold there each pound for three
        pounds of silver, 14. 249.

  _China_ Dishes how made there, _ibid._
    A way found in _Europe_ to make _China_-Dishes, 7. 127.

  _Chymists_ in _China_ pretend to make Gold, and promise Immortality, 14.
      249.

  _Cold_, see M. _Boyles_ History, abbrev. More Inquiries, and some answers
      touching _Cold_, 19. 344.
    How _Cold_ may be produced in hottest Summers by _Sal Armoniack_,
        discovered by M. _Boyle_, 15. 255.
    Some suggestions see remedies against _Cold_, by D. _Beale_, 21. 379.

  _Comets._ The motions of the Comet of _Decemb._ 1664. predicted, 1. 3.
    _Cassini_ concurs; 2. 17.
    _Auzout_, who first predicted the motion, reflects upon _Cassini_, 2.
        18. and predicts the motions of the second Comet of _March, April_
        1665. n. 3. 36.

  Controversies and Discourses, some at large, concerning _Comets_, n. 1.
      p. 3. n. 2. p. 17, 18. n. 3. p. 36. n. 6. p. 104. n. 9. p. 150. n.
      17. p. 301.
    Many considerables abbreviated, n. 6. p. 104. n. 17. p. 301.

                  D.

  _Damps_ in Mines pernicious, 3. 44. and how killing, _ibid._

  _Directions_ for Seamen bound for far Voyages, by M. _Rook_, 8. 140.
    Mr. _Boyles_ Inquiries, 18. 315.

  Philosophical _Directions_ or Inquiries for such as Travel into _Turky_,
      20. 360.

  _Directions_, or general Heads for a natural History of a Countrey, by M.
      _Boyle_, 11. 186.

  _Directions_ or Inquiries concerning _Mines_, by the same, 19. 330.

  _Diamonds_ where, and how the fairest are discover'd, 18. 327.

                  E.

  The _Earthquake_ about _Oxford_, Anno 1665. described by D. _Wallis_, 10.
      181.
    by M. _Boyle_, 11. 179. noting the Concomitants thereof by _Baroscope_
        and _Thermometer_.

  The _Earth_'s Diurnal motion prov'd by the motion of the Comets, 1. 6. &
      7.
    especially by the slow motion of the second Comet, 3. 39.
    See M. _Auzout_, confirm'd by M. _Hevelius_, 6. 105.
    confirm'd also by the Tydes at Sea, 16. 265.

  The _Eclipse_ of _June_ 22, 1666. accurately observ'd at _London_, 17.
      245.
    at _Madrid_, _ibid._
    at _Paris_, 17. 246.
    at _Danizick_, drawn in accurate Cuts, n. 19. 347. n. 21. p. 369.

  _Elephants:_ How to escape, or to combat with them, 18. 328.

  _Eeles_ discover'd under Banks in Hoar-Frosts, by the Greens of the Banks
      approaching, 18. 383.

                  F.

  The _Fleshy_ parts of the Body which are usually reputed, and do seem
      void of Vessels, are argued to be full of Vessels, by D. _King_, 18.
      316.

  _Friction_ and sometimes _Touch_, how sanative, by several Examples, 12.
      206.

  _Frictions_ much used by Physitians in _China_ with good success, 14.
      249.
  {402}

                  G.

  _Geometricians_ censur'd by M. _Hobbs_, 14. 153.
    defended by D. _Wallis_, 16. 289.

  The method of teaching _Geometry_ reform'd, 15. 261.
    See _Euclidis Elementa novo ordine_, among the Books.

                  I.

  _Inquiries_, see Directions, suprá.

  _Ice_ and Snow how to be preserv'd in Chaffe, and how Snow-houses are
      made in _Livorn_, 8. 139.

  _Insects_, in swarms pernicious in some Countries; the cause of them, and
      what Remedies, 8. 139.
    some _Insects_, commonly believed poysonous, not so, by M. _Fairfax_,
        22. 391.

  To find the _Julian_ period by a new and easie way, 18. 324.

  _Jupiter_'s Rotation by degrees discover'd in _England_ and _Italy_, n.
      1. p. 3. n. 4 p. 75. n. 8. p. 143. n. 9. p. 173. n. 12. p. 209. n.
      14. p. 245.

                  K.

  _Kermes_, how gather'd and used for Coloration, describ'd with many
      considerables, 20. 362.

                  L.

  _Light_, to examine what figure or celerity of motion begetteth or
      increaseth Light or Flame in some Bodies, by D. _Beale_, 13. p. 226.
    _Shining_ Worms found in Oysters, 12. 103.
    The Bononian Stone duly prepar'd continues _light_ once imbibed above
        any other substance yet known amongst us, 21. 375.
    The loss of the way of preparing the same for shining, feared, _ibid._

  _Longitudes_ at Sea, how to be ascertain'd by Pendulum-Watches, 1. 13.

  _Lungs_ and Windpipes in Sheep and Oxen strangely stopt with Hand-Balls
      of Grass, 6. 100.

                  M.

  _Marbles_, that a liquor may be made to colour them, piercing into them,
      7. 125.

  _Mars_, by what steps and degrees of diligence discover'd to be
      turbinated, both in _England_ and _Italy_.  Compare n. 10. p. 198.
      and n. 14. 239, 242. see the Schemes there.

  _May-dew_ examin'd by various Experiments, by M. _Henshaw_, 3. 33.

  _Mechanical_ Principles in a Geometrical method, explicating the nature
      or operation of Plants, Animals, 8. 325.

  _Medicins_ in _China_ consist for the most part of Simples, Decoctions,
      Cauteries, Frictions, without the use of Blood-letting, 14. 249.
    The _Physitians_ there, commended for speedy Cures, and easie, _ibid._

  _Mediterranean Sea_, whether it may be join'd with the Ocean, debated, 3.
      41.

  _Micrography_ epitomized, 2. 27.
    M. _Auzout_'s Objections to a part of it; vid. the new way of grinding
        Spherical Glasses by a Turn-lath, 4. 57.
    M. _Hooks_ answer thereunto, 4. 64. both at large.

  _Mercury_-Mines in _Friuli_, and the way of getting it out of the earth,
      2. 21.

  _Mineral_ Inquiries, see Directions, Engins, Artificial Instruments.
    _Mineral_ at Liege yielding Brimstone and Vitriol; and the way of
        extracting them, 3. 35.
    How Adits and _Mines_ are wrought at Liege, 5. 79.
    A Stone in _Sueden_ yielding Sulphur, Vitriol, Allum and Minium, and
        how, 21. 375.
    See _Kircher_'s Mundus Subterraneus abbr. 6. 109.

  _Monsters_, a Calf deform'd, and a great stone found in a Cows womb, n.
      1. 10.
    a _Colt_ with a double eye in one place, 5. 85.

  _Moons_ Diameter how to be taken, and why increased in the Solar Eclipse
      of _Jun._ 22. 1666. n. 2. p. 373.
    see _Planets_.
    What discoverable in the _Moon_, and what not.
    _Moons Eclipses_ how to take without inconvenience, 22. 387.

  _Mulberry-Trees_ how to be cut low, and easie to be reach'd, for relief
      of Silk-worms, in _China_, 14. 249.
    in _Virginia_, 12. 202.
    see Silk.

                  N.

  _Nile's_ Inundations, the cause attributed to _Niter_, by _Dela Chambre_;
      opposed by _Vossius_. See both in the _List of Books_, 14. 251. and
      17. 304.

  The _North-Countries_ of _Poland_, _Sweden_, _Denmark_, &c. are warm'd by
      the influence of the _Royal Society_, 19. 344.
  {403}

                  O.

  _Ocean_, what Seas may be joined with it, 3. 41.

  _Opticks_, Campani's Glasses do excell Divini's; 'tis easie by them to
      distinguish people at four Leagues distance, 2. 131. and 12. 209.
    What they discover in _Jupiter_ and _Saturn_, 1. 1. and 2.
    The proportions of Apertures in Perspectives reduced to a Table by M.
        _Auzout_, 4. 55.
    Animadverted upon by M. _Hook_, 4. 69.

  How to illuminate Objects to whatsoever proportion, proposed by M.
      _Auzout_, 4. 75.

  _Hevelius_, _Hugenius_, and some in _England_, endeavour to improve
      Optick Glasses, 6. 98.

  Seigneur _Burattini_'s advance in the same inquired after, 19. 348.
    some answer to it from _Paris_, 22. 374.

  _Divini_ makes good Optick Glasses of Rock-chrystal, that had veins (_if
      he mistook not somewhat else for veins_) 20. 362.

  To measure the distance of Objects on earth by a Telescope, undertaken by
      M. _Auzout_, and others of the _Royal Society_, 7. 123.

  How a Telescope of a few feet in Diameter may draw some hundreds of feet,
      7. 127.

  How a Glass of a small convex-sphere may be made to reflect the Rayes of
      Light to a _Focus_ at a far greater distance than is usual, 12. 202.

                  P.

  _Parsley_, to make it shoot out of the ground in a few hours, see _Hon.
      Fabri_ 18. 325.

  _Pictures_, a curious way in _France_ of making lively Pictures in Wax,
      and Maps in a low relieve, 6. 99.

  The cause why _Pictures_ seem to look upon all Beholders, on which side
      soever they place themselves, 18. 326.

  Ancient _Paintings_ compar'd with the Modern, and a judgment of the
      _Paintings_ in several Ages, their perfections, and defects, see M.
      _Felibien_, 21. 383.

  _Petrification_, in the wombs of Women, 18. 320.
    in a Calf in the Cows womb, 1. 10.
    _Stones_ found in the heart of the Earl of _Belcarris_, 5. 86.
    Part of an Elm by incision, or otherwise, _petrified_ a foot above the
        root and ground, 19. 329.
    Wood _petrified_ in a sandy ground in _England_; and of a Stone like a
        Bone or Osteocolla, 6. 101.
    A _Stone_ of excellent vertues found in the head of a Serpent in the
        _Indies_, 6. 102.
    The causes of _Petrification_ inquired, 18. 320.

  _Planets_, See _Jupiter,_, _Mars_, _Saturn_, _Sun_, _Moon_; which are
      turbinated, and which not, 8. 143.
    To find the true distances of the Sun and Moon from the earth, 9. 191.

  _Physitians_ of _China_ commended, see _Medecins_.

  _Preservation_, to preserve small Birds taken out of the shell, or other
      _Fætus_'s, for discoveries, 12. 198.

  _Pulses_ of the Sick how diligently, and to what good purposes observ'ed
      in _China_, 14. 249.

                  R.

  _Rainbows_ strangely posited, 13. 219.

  _Raining_ of Ashes, and how, 21. 377.

  _Rice_ prospers best in watery places, see _Marishes_, 18. 328.

                  S.

  _Salamander_, how it extinguishes fire, and feeds by licking _Indian_
      earth, 21. 377.

  _Salt_ by excessive use stiffens, and destroys the body, 8. 138.

  _Salt-Springs_, see _Springs_.

  _Salt-Peeter_ how made in the _Mogols_ Dominions, 6. 103.

  The proportion of _Salt_ in best Salt-Springs; and what grounds or signs
      of best _Salt_, 8. 136.

  _Sea-fluxes_, the cause proposed by way of a new Theory, by Dr. _Wallis_,
      16. 263. see _Tydes_.

  _Seas_, whether they may be united, 3. 41.

  _Silk-Worms_ and _Silk-Trade_ sollicited, 5. 87. and 2. 26. and 12. 201.

  _Snakes_, how they differ from Vipers, 8. 138.

  _Rattle-Snakes_, how sometimes kill'd in _Virginia_, 3. 43 and 4. 78.

  _Snow-houses_ directed, and how to preserve Ice and _Snow_ in Chaffe, 8.
      139.

  _Springs_, of peculiar note, n. 7. 127. n. 8. 133. 135. and 136. n. 18.
      323.
  {404}

                  T.

  _Taste_, the Organ and Nature of it, 20. 366.

  _Thunder_ and Lightning, the Effects examined, n. 13. 222. n. 14. 247.

  _Tydes_, the causes proposed, 16. 263.
    See a further examination by a severe History of Tydes, Winds, and
        other circumstances directed, n. 17. n. 18. n. 21.

  _Trees_ of Oak how found under-ground in Moors or Marishes, 18. 323.

  _Thee_, in _China_ and what; how exchanged there for dried leaves of Sage
      by the _Dutch_, 14. 249.

                  W.

  _Whale-fishing_ about _Bermudas_, and _New England_, how it is performed,
      n. 1. 11. n. 8. 132.

  _Wind_, how to be raised by the fall of water, without any Bellows, 2.
      25. shewed in a draught.

  _Worms_, that eat holes in stones, feeding on stone, 28. 321.

       *       *       *       *       *


{405}

The more

_NATURAL METHOD._

  I. A Natural History of all Countries and Places, is the foundation for
      solid Philosophy, _See_ Directions, Inquiries, and Instructions for a
      Natural History of a Countrey, n. 11. p. 186.

  _See_ it in part exemplified in the _History of England_, begun by Dr.
      _Merret_ in his _Pinax_, 20. 364.

  _See_ the cause of Tydes proposed by D. _Wallis_, 16. 263.

  _See_ the further Examination by a severe History of Tydes, Winds, and
      other Concomitants or Adherents, directed, n. 17. n. 18, n. 21.

  _See_ the Inquiries concerning the Seas, and Sea-waters, n. 18. 315.

  _See_ Directions for Seamen bound for far Voyages, 8. 140.

  _Kircher_'s Account of the Subterraneous World, 6. 109.

  Mr. _Boyle_'s Directions and Inquires touching Mines, 19. 330.

  Philosophical Directions and Inquiries for such as Travel into _Turky_,
      n. 20. 300.

  The Relation of M. _de Bourges_, 18. 324.

  M. _Thevenots_ Relation of divers curious Voyages, &c. more particularly
      of _China_, 24. 248.

  The causes of the inundation of the _Nile_, disputed by _Dela Chambre_
      and _Vossius_. In the _List of Books_.

  _See_ Mr. _Boyle_'s Mechanical Deductions, and Chymical Demonstrations of
      the _Origine of Forms and Qualities_, 11. 191.

  _See_ the Application of these Mechanical Principles more particularly to
      the Nature, Operation, and Generation of Plants and Animals, and to
      our humane Contexture, in a Geometrical method, by _Hon. Fabri_, 18.
      325.

  _See_ Mr. _Boyle_'s History of Cold and Thermometers, n. 1. p. 8. n. 3.
      p. 46.

  The History of Winds and Weather, and all changes of the Air (especially
      in relation to the weight) observable by the Baroscope, n. 9. n. 10,
      n. 11.

  _Light_, some special search into the causes, and some peculiar Examples.
      _See_ above in _Light_.

  _Petrification_ sollicited, see Petrification, Stone.

  The Earths Diurnal Rotation, see Earth _suprá_.

  Adventurous Essayes in Natural Philosophy, see _Guarini_, 20. 365.

  Earthquakes, and their Concomitants observed, n. 10. n. 11.

  The effects of Thunder and Lightning, examin'd, see _Thunder_, n. 13.
      222. n. 14. 247.

  The raining of Ashes and Sand at great distance from the Mount
      _Vesuvius_, see _Raine_, 21. 377.

  Springs, and Waters of peculiar Note, see _Springs_.

  Insects in Swarms how begotten; pernicious, and how destroyed, 8. 137.

  Monsters, or Irregularities in Nature. The _Calf_, _Colt_, suprá.

  Four Suns at once, and two strange Rainbows, 13. 219.

  _See_ the statical position and tendency or gravitation of Liquids, in M.
      _Boyle_'s _Hydrostatical Paradoxes_, 8. 145.

  _See_ in M. _Hooks_ Micrography, a History of minute Bodies, or rather of
      the minute and heretofore unseen parts of Bodies; it being a main
      part of Philosophy, by an artificial reduction of all gross parts of
      Nature to a closer inspection.

  _Medicinals_, see Medicine. Physitians, _China_. Friction, Dr.
      _Sydenham_. Dr. _Lower_, Friction, _suprá._ n. 4. 77. n. 12. 206.

  _Anatome_, see _Steno de Musculis & Glandulis_.
    How a juyce in the stomack dissolves the shells of Crafishes, _ibid._

  Graeff _de Succo Pancratico_;
    that Flesh hath Vessels, n. 18. 316.
    Blood degenerated to resemble milk, n. 6. 117.
    The Transfusion of blood, 20. 353.
    The organ and nature of _Taste_, 20. 366.
  {406}

  _Salt_ too much stiffens and destroys the Body, 8. 138.

  II. _Singularities_ of Nature severely examin'd.

  The ordering of _Kermes_ for Color. n. 20. 362.

  How the _Salamander_ quencheth Fire, and lives by licking the Earth. n.
      21. 377.

  Whether Swallows do lie under water in Winter, and revive in Summer? n.
      19. 350.

  Whether the _Hungarian Bolus_ like the _Armenus_? 1. 11.

  _Rattle-Snakes_ how kill'd in _Virginia_, 3. 43.

  _Snakes_ and Vipers how they differ, see _Snakes_ above.

  The Qualities and Productions of _May-dew_, 3. 1.

  Damps in Mines how they kill, 3. 44.

  Teeth growing in aged persons, 21. 380.

  Steams and Expirations of the Body how stopp'd; and the stoppage
      dangerous or mortal, 8. 138.

  Shining Worms in Oysters, 12. 203.

  III. _Arts_, or Aids for the discovery or use of things Natural. _See_
      Artificial Instruments in the _Table_.

  Agriculture, _see_ the Inquiries, 5. 91.

  English Vineyards vindicated, see in the _Catalogue of Books_.

  Geometry, see _Euclid_ methodized for Facility, _Fermat: in the Catalogue
      of Books._

  Astronomy, see Astronomical Remarks. _Bullialdus_, _Hevetius_, _Comets_,
      _Planets_, _Saturn_, _Jupiter_, _Mars_, _Sun_, _Moon_, _Eclipses_.

  Opticks _see_ that Head in the _Table_.

  Picture, _see_ that Head in P. and _Felibien_ in the _Catalogue of
      Books_.

  How to paint Marbles within, _see_ the Head _Marble_.

  _Pendulum_ Watches to ascertain _Longitudes_ at Sea, 1. 13.

  Whale-fishing about _Bermudas_, 1. 11. and 8. 132.

  Silk-trade sollicited in _France_, _Virginia,_ see _Silk_ in the _Table_.

  Eeles how to be found in Frosts, 17. 323.

  Winds raised to blow by the fall of water without Bellows, 2. 25. shew'd
      in a _Cutt_.

  Elephants enraged, how to escape or subdue, 18. 328.

  Seas and vast waters, whether they may be united to the main Ocean, 3.
      41.

  To proportion the distance necessary to burn Bodies by the Sun; and
      shewing, why the Reflections from the Moon and other Planets do not
      burn, 4. 69.

  The Art of making _Salt-Peeter_, as practised in the _Mogols_ Dominions,
      6. 103.

  To make _China_-Dishes, 14. 249.
    expected from Seigneur _Septalio_ to be made in _Europe_, 7. 127.

  To convey blood of one Animal, or other Liquors, into the blood of
      another Animal, 20. 353.

  To preserve Ice and Snow by Chaffe, 8. 138.

  To preserve Ships from being Worm eaten, 11. 190.

  To preserve Birds taken out of the Eggs, or other small _Fætus_'s, for
      Anatomical, or other Discoveries, 12. 199.

  To allay the heat in hottest Summer, for Diet or Delight, 15. 255.

  Remedies against extream Cold suggested, 21. 379.

  Trees of Oak as black as Ebony discover'd, and taken up out of Moors and
      Marshes in draughty weather, 11. 323.

       *       *       *       *       *


  _Note,_

That though in this last Head there is repeated the _Transfusion_ of Blood,
because the Operation is an Art requiring diligence, and a practised hand
to perform it for all advantagious Discoveries, and so to be distinguish'd
from the _Anatomical_ Account; yet that there is not affected noise and
number, may well appear by reviewing and comparing the particulars of
_Artificial Instruments_ in the {407} _Table_, where sometimes one Engin or
Instrument may minister Aid to discover a large branch of Philosophy, as
the _Baroscope_, an _Optick Glass_, &c.

And very particularly M. _Rook_'s directions for Seamen, which specifies
Instruments, may hereunto belong.

And sometimes in one of the Discourses herein mention'd, and abbreviated,
there are almost as many Artificial Inventions, as Experiments; as in Mr.
_Boyle_'s Hydrostatical Experiments: Besides all the Chymical Operations,
recited in the _Treatise_ of the _Origine of Forms_, &c.

[Greek: Ouk en tôi megalôi to eu, all' en tôi eu to mega.]

       *       *       *       *       *


ERRATA.

Pag. 392. lin. 23. blot out, _as_. ibid. lin. 24. read _of the Soul_.

       *       *       *       *       *


FINIS.

{408}

       *       *       *       *       *


In the _SAVOY_,

Printed by _T. N._ for _John Martyn_, and _James Allestry_, Printers to the
_Royal Society:_ And are to be sold at their Shop without _Temple-Bar_, and
in _Duck-lane_, 1667.

       *       *       *       *       *


       *       *       *       *       *

Corrections made to printed original.

Page 6, "But that, which he judgeth most remarkable": 'rewarkable' in
original.

Page 29, "the strange Phænomena of Glass-drops": 'Grass-drops' in original.

Page 33, "Of the Mineral of Liege": 'Leige' in original.

Page 103, "by the feet of People they tread it": 'traed' in original.

Page 104, "sell us a Maon of 6 pounds": 'a Moan' in original.

Page 109, "Of the Mundus Subterraneus of Athanasius Kircher": 'Athansius'
in original.

Page 110, "the Earth, its Heterogeneous Nature": 'Mature' in original.

Page 110-1, "the manifold Productions made therein": 'Produ-actions' in
original, across page-break; the catch-word is 'ctions'.

Page 111, "Secondly, of the Transformation of Juices": 'Transforma-on' in
original, across line-break.

Ibid., "little Fishes, and Plants are Intombed therein": 'Planets' in
original(!).

Page 115, "A Relation of strange Earth-quakes": 'Eath-quakes' in original.

Page 121, "or that none of them burn at this time": 'or or' across two
lines in original.

Page 141, "together with all the Accidents": 'Ac-dents' in original, across
page-break; the catch-word is 'cidents'.

Page 142, "take exact care to observe the Trade-Winds": 'Trade-Wines' in
original.

Page 148, "1/16 at the bottom in diameter": 'the the' in original.

Page 172, "Jupiter turns about his Axis in 9. hours 56. minutes": '9. dayes
56. minutes' in original (which contradicts the rest of the paragraph).

Page 228, "and by better Microscopes": 'bet-bet' in original, across
line-break.

Page 243, para. 5. numbered 4. in original.

Ibid., "very distant from one another": 'anothe' in original.

Page 297, "that some understanding Persons at London, or Greenwich, but
rather nearer the Sea,": 'that' and 'Sea,' transposed in original (first
words of successive lines).

Page 315 (Sidenote), "the Differences of Gravity he might meet with":
'Garvity' in original.

Page 315, "from the greater or lesser Proportion of Salt": 'gteater' in
original.

Ibid. "the Stones, Minerals and Vegetables to be found there": 'Vetegables'
in original.

Page 315, "the Deity, which we worship": 'Diety' in original.

Page 335, para. 35. numbered 75. in original.

Page 364, "PINAX Rerum Naturalium BRITANNICARUM": 'BRITANIARUM' in original
(cf. contents page & volume index).

Page 376, "carry into the Work-house": 'Work-honse' in original.

Page 379, "by Art, or Mechanical contrivance": 'contri-trivance' in
original, across line-break.

Page 381, "the Canini of the left Cheek": 'Check' in original.

Page 400, Astronomical Remarks of a New Star: "which Kepler saw A. 1601.":
'1661' in original (the remaining dates in this index entry do not well
match the article).