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TRANSCRIBER'S NOTES

Italic text is denoted by _underscores_ and bold text by =equal signs=.

The picture of a pointing finger, known in typography as an index, a
manicule, or a fist, has been rendered in this text version as "=>".

Subscripts have been rendered using braces, so that the formula for
sulphuric acid is shown as "H{2}SO{4}", and the formula for water, if it
had appeared, would have been shown as "H{2}O".

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[Illustration: SCIENTIFIC AMERICAN]

  A WEEKLY JOURNAL OF PRACTICAL INFORMATION, ART, SCIENCE, MECHANICS,
                      CHEMISTRY, AND MANUFACTURES.

  Vol. XXXIX.--No. 6      NEW YORK, AUGUST 10, 1878     $3.20 per Annum.
    [NEW SERIES.]                                  [POSTAGE PREPAID.]




              THE PARIS EXHIBITION.--A SKETCH IN THE PARK.

Our engraving, which represents a portion of the park at the Paris
Exhibition grounds, needs little mention beyond that it is one of those
delightful retreats so refreshing to the weary visitor, who, tired out
with tramping about the buildings and grounds, is only too pleased to
refresh his eyes with some of that exquisite miniature water scenery
which is scattered about the grounds. We take our illustration from the
London _Graphic_.

       *       *       *       *       *




                 =Improvements in Silk Worm Breeding.=

_Galignani_ states that a very curious discovery has just been made,
which, if found as practicable in application as it seems to promise,
may create a very considerable change in the production of silk. It is
nothing more nor less than the possibility of obtaining two yields in
the year of the raw material instead of one, as at present. The moth
lays its eggs in May or June, and these do not hatch before the spring
of the following year. But sometimes they are observed to hatch
spontaneously ten or twelve days after they are laid. It was such a
circumstance as this coming to the attention of M. Ducloux, Professor of
the Faculty of Sciences at Lyons, that led him to undertake a series of
experiments on the subject, by means of which he has found that this
premature hatching can be produced at will. The means for effecting the
object are very simple--rubbing the eggs with a hair brush, subjecting
them to the action of electricity, or more surely still by dipping them
for half a minute in concentrated sulphuric acid. M. Bollé, who has also
turned his attention to the same subject, states that the same effect is
produced by hydrochloric, nitric, or even acetic and tartaric acid.
Finally, a submersion of a few seconds in water heated to 50° Cent.
(122° Fah.) is equally efficacious. However, M. Ducloux states that the
operation must be performed while the eggs are quite young, the second
or third day at the outside. When this new hatching is accomplished the
mulberry tree is in its full vigor, and the weather so favorable that
the rearing of the worm is liable to much less risk than during the
early days of spring, when the sudden atmospheric changes are very
detrimental, and frequently fatal to the growing caterpillars.

       *       *       *       *       *




                   =The Natural History of the Eel.=

According to the reports of shad fishermen, the chief enemy of the shad
is the eel, which not only follows that fish up the streams and devours
the spawn, but often attacks the shad after they are caught in the nets.
Entering the shad at the gill openings the eels suck out the spawn and
entrails, and leave the fish perfectly clean. The finest and fattest
shad are the ones selected. It is a curious circumstance that of a fish
so well known as the eel so many of its life habits should be in
dispute. An animated discussion has been going on in Germany quite
recently with regard to the natural history of this fish, and in a late
number of a scientific journal the following points are set down as
pretty well substantiated. Though a fresh water fish which passes the
greater part of its life in rivers, the eel spawns in the sea. That it
is viviparous is extremely improbable. The eel found in the upper waters
of rivers is almost always female. At the age of four years it goes down
to the sea to spawn and never returns to fresh water. The spawning
process is somehow dangerous to the eel, thousands being found dead near
the mouths of rivers, with their ovaries empty. The descent of the fish
to the sea does not appear to take place at any definite period, but is
probably dependent on the season for spawning. The male is always much
smaller than the female, and never exceeds half a yard in length. The
males never ascend to the head waters of rivers, but keep continually in
the sea or in the lower reaches of the river. Nothing is definitely
known about the spawning season, though it is probable that the eggs are
deposited in the sea not far from the mouths of rivers.

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[Illustration: THE PARIS EXHIBITION.--A SKETCH IN THE PARK.]

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[Illustration: "Scientific American." In Gothic script]

                           Established 1845.

                  MUNN & CO., Editors and Proprietors.

                          PUBLISHED WEEKLY AT

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  is a distinct paper from the SCIENTIFIC AMERICAN. THE SUPPLEMENT is
  issued weekly; every number contains 16 octavo pages, with handsome
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=Combined Rates.=--THE SCIENTIFIC AMERICAN and SUPPLEMENT will be sent
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The safest way to remit is by draft, postal order, or registered letter.

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                 =Scientific American Export Edition.=

The SCIENTIFIC AMERICAN Export Edition is a large and splendid
periodical, issued once a month. Each number contains about one hundred
large quarto pages, profusely illustrated, embracing: (1.) Most of the
plates and pages of the four preceding weekly issues of the SCIENTIFIC
AMERICAN, with its splendid engravings and valuable information; (2.)
Commercial, trade, and manufacturing announcements of leading houses.
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         VOL. XXXIX., No. 6. [NEW SERIES.] _Thirty-third Year._
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                  NEW YORK, SATURDAY, AUGUST 10, 1878.
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                              =Contents.=

          (Illustrated articles are marked with an asterisk.)

  American goods, excellence of              89
  Astronomical notes*                        90
  Astronomical observation*                  91
  Brass, recipe for cleaning [4]             91
  Cancer, treatment of                       85
  Chloride of lime, to neutralize [6]        91
  Coal, distillation of*                     85
  Discoveries, Prof. Marsh's recent          90
  Drawings, how to mount [19]                91
  Drawings, printing copies of [9]           91
  Edison telephone and Hughes' microphone    80
  Education, industrial                      90
  Eel, natural history of the                79
  Electro-magnet, to construct [12]          91
  England, wages in                          85
  Engraving, photographic                    82
  Exhibition, American Institute             84
  Export edition, Scientific Amer.           80
  Fire, chemicals to extinguish [22]         91
  Flour, explosiveness of                    87
  Gas, saw tempering by natural              87
  Germany, labor in                          89
  Gold, how to melt [18]                     91
  Hair, removing superfluous [1]             91
  Hughes, letter from Prof.                  80
  Industrial enterprises, new                84
  Ink to rule faint lines [7]                91
  Inventions, new                            86
  Inventions, new agricultural               86
  Inventions, new engineering                87
  Inventions, new mechanical                 89
  Iron making, progress of                   80
  Journalism, crooked                        88
  Lathes, attachment for*                    86
  Lemon verbena, new use for                 89
  Life, minute forms of                      85
  Lime light, how to make [14]               91
  Main joints, street                        88
  Mormons, hint from the                     86
  N. Y. Capitol, machinery for               87
  Paris Ex., Japanese Building*              87
  Paris Exhibition, the park*                79
  Patent law, our                            84
  Pens, fountain                             80
  Petroleum June review                      90
  Petroleum oils as lubricators              89
  Petroleum, short history of                85
  Plants, etc., influence of light on        89
  Poisoning of a lake, remarkable            90
  Production, ill-balanced                   89
  Production, more perfect                   88
  Puddling, mechanical*                      82
  Quick work                                 86
  Rainfall, decrease of N. Y.                86
  Rhinoceros Hornbill, the*                  87
  Shad hatching, successful                  88
  Shellac, to dissolve bleached [2]          91
  Shoes, dressing for ladies' [21]           91
  Silk worm breeding                         79
  Substances, how to rate [3]                91
  Sun, the*                              80, 81
  Teeth, replanting, etc.                    84
  Telephone, science promoter                80
  Thermometer, new deep sea*                 83
  Timber, ribs on surface of [17]            91
  Valve, new steam*                          86
  Velocipede feat, extraordinary*            89
  Wires, copper finish to [24]               91
  Wood, to make sound boards [11]            91
  Wool product of the world                  88
  $150,000,000 a year, trying to save        90




                         TABLE OF CONTENTS OF
                  =THE SCIENTIFIC AMERICAN SUPPLEMENT=
                               =No. 136,=
                 =For the Week ending August 10, 1878.=

  I. ENGINEERING AND MECHANICS.--The Manufacture of Wrought Iron Pipe.
      Bending the Sheets. Welding the Tube. Manufacture of Gas Pipe.
      Polishing and Smoothing. 4 figures.

        Improved Marine Engine Governor. 1 figure.--Improved Screw
      Steering Apparatus. 3 figures.--West's Reversing Gear. 1
      figure.--Engineering in Peru. The Oroya Railroad over the summit
      of the Andes. A remarkable engineering feat. The famous Cerro de
      Pasco Silver Mines. Extensive Coal Fields.

  II. TECHNOLOGY.--Coal Ashes as a Civilizer. Grading. Coal Ashes as a
      Fertilizer.--Utilization of the Waste Waters of Fulling Mills and
      Woolen Works.--Suggestions in Decorative Art. Marquetry Ornaments
      from Florence. 3 illustrations.
        Useful Recipes. By J. W. PARKINSON. Cream cake. Kisses. Apples a
      la Tongue. Mead. Bread without yeast. Biscuit. Doughnuts. Glaire
      of Eggs. Crumpets. Ratafia de Framboises. Ratafia de Cerises. To
      color sugar sand. Raspberry and currant paste. Cheese cake.
      Cocoanut macaroons. Orange slices. Ice cream. Fruit juices. Lady
      fingers. White bride cake. Scalloped clams. Iced souffle. Sugar
      for crystal work. To restore the fragrance of oil of lemon. Family
      bread.

  III. FRENCH INTERNATIONAL EXPOSITION OF 1878.--Tobacco at the
      Exhibition. Manufacture of snuff. The two processes of
      fermentation. The grinding. The packing of the snuff. Manufacture
      of chewing tobacco, etc.
        New Cutting Apparatus for Reapers. 1 figure.--The Algerian
      Court. 1 illustration.--The French Forest Pavilion. 1
      illustration.

  IV. CHEMISTRY AND METALLURGY.--A Reducing Agent.--Climbing
      Salts.--Chloride of Lime.--Action of Watery Vapor.--The Active
      Principles of Ergot.--Cadaveric Alkaloids.
        Outlines of Chemistry. By HENRY M. MCINTIRE.

  V. ARCHITECTURE AND BUILDING.--A Cottage Costing $150. By S. B. REED,
      Architect. Plans for cheap summer residence for family of four
      persons. Dimensions, construction, and estimate for all materials
      and labor, with 6 figures.--Buildings in Glass. Improved method of
      constructing conservatories, 2 figures.--Buildings and
      Earthquakes. On structures in an earthquake country. By JOHN PERRY
      and W. E. AYRTON, Japan. Also a new Seismometer for the
      measurement of earthquakes.

  VI. NATURAL HISTORY, GEOLOGY, ETC.--Colors of Birds and
      Insects.--Microscopy. Minute and low forms of life. Poisonous
      Caterpillar. Sphærosia Volvox. An Australian Polyzoon.
        A Chinese Tornado.

  VII. MEDICINE AND HYGIENE.--Nervous Exhaustion. By GEORGE M. BEARD,
      M.D. Symptoms continued. Mental depression with timidity; morbid
      fear of special kinds; headaches; disturbances of the nerves and
      organs of special sense; localized peripheral numbness and
      hyperæsthesia; general and local chills and flashes of heat; local
      spasms of the muscles. Suggestions and treatment. Electricity.
      Application of cold; kind of food; exercise; medicines.
        The Art of Preserving the Eyesight. V. From the French of Arthur
      Chevalier. Presbyopy, or long sight. Symptoms. Causes. Artificial
      light. Franklin's spectacles. Spectacles for artists. Hygiene for
      long sight, and rules. Myopy, or short sight. Dilation of pupil,
      and other symptoms of myopy. Glass not to be constantly used in
      myopy. How to cure slight myopy. Choice of glasses. Colored
      glasses for short sight. False or distant myopy, and glasses to be
      used, 5 figures.

  VIII. MISCELLANEOUS.--The Repair of the Burned Models after the Patent
      Office Fire of 1877. By GEORGE DUDLEY LAWSON. An interesting
      description of the importance and difficulty of the work, and the
      enterprise and care shown. Reconstructing complicated models from
      miscellaneous fragments.
        Verneuil, Winner of the Ascot Cup, 1 illustration.

Price 10 cents. To be had at this office and of all newsdealers.

       *       *       *       *       *




                       =PROGRESS OF IRON MAKING.=

The success of the Dank's puddling furnace fired with pulverized coal
seems to be no longer a matter of doubt in England. It is stated that
Messrs. Hopkins, Gilkes & Co., the well known iron makers of the North
of England, have succeeded in turning out from it from Cleveland pig
alone iron capable of bearing tests which Staffordshire iron has not yet
surpassed. The English iron manufacturers in their struggle with us are
wisely taking advantage of every improvement in their line to keep ahead
of us, and are likely to be successful unless our manufacturers arouse
from their fancied security.

We are now underselling the English at home and abroad in many articles
of manufacture, because so much of our work is done by machinery, and is
consequently better and cheaper than can be produced by hand labor at
the lowest living rate of wages; but so soon as the English masters and
workmen shall fully appreciate this fact, the same machines run there
with cheaper labor will deprive us of our present advantages.

Already we notice several instances in which the workmen, renouncing
their prejudices, have willingly consented to the substitution of
machine for hand work, and we doubt not that the success of these
innovations, conjoined with the pressure of the times, will ere long
create a complete revolution in the ideas of the British workmen, so
that instead of longer opposing they will demand the improved appliances
and facilities for work, converting them from rivals or opponents to
allies. Such a radical change is not necessarily far in the future, for
the logic of it has long been working in the brains of both masters and
men and may reasonably bear fruit at any time. We fear that when this
time arrives our makers of iron, especially, will wake up to the
consciousness that they have not kept up with the advance.

       *       *       *       *       *




               =THE TELEPHONE AS A PROMOTER OF SCIENCE.=

Every new thing, whether it be in the realm of mind or matter, has an
influence on whatever existed before, of a similar kind, to modify,
develop, and improve it, or to doom it to oblivion. Whatever is new
necessitates a better knowledge of the old, so that the world gains not
only by the acquirement of the new thing, but also by a better
understanding of things already known.

A discovery, published, sets a thousand minds at work, and immediately
there is a host of experimentalists who, in their desire to make and try
the new thing for themselves, begin without a knowledge of the science
or art to which the discovery pertains, and inevitably fail. After
failure comes research, which to be of value must be extended. Every
investigator can recall the novelty that induced his first experiments,
and can recount his trials in his search for information.

Among the inventions or discoveries that have induced extended
experiment, the telephone may, without doubt, be mentioned as the chief,
for no sooner was the first speaking telephone brought out than here and
there all over the country it was imitated. Persons who never had the
slightest knowledge of electrical science had a desire to see and test
the telephone. To do this first of all requires a degree of mechanical
skill. Acoustics must be understood, and a knowledge of the four
branches of electrical science is requisite, as the telephone involves
galvanism, magnetism, electrical resistance, induction, and many of the
nicer points which can be understood by investigation only, and this not
only in the direction indicated, but in the allied branches of physics
and also in chemistry. Familiarity with these things develops a
scientific taste that will not be easily satisfied. The characteristic
avidity with which the American people seize upon a novelty has been
wonderfully exemplified by the manner in which the telephone mania has
spread. In consequence of this science has received an impetus, and now
we have everywhere embryo electricians and experimentalists, where
before were only the unscientific.

       *       *       *       *       *




                    =LETTER FROM PROFESSOR HUGHES.=

We print in another column a letter received from Mr. D. E. Hughes
concerning the distinction he finds between his microphone and Mr.
Edison's carbon telephone. Mr. Hughes is very confident that the two
inventions have nothing in common, and that they bear no resemblance to
each other in form, material, or principles.

We would not question Mr. Hughes' sincerity in all this. No doubt he
honestly believes that the invention of Mr. Edison "represents no field
of discovery, and is restricted in its uses to telephony," whilst the
"microphone demonstrates and represents the whole field of nature." But
the fact of his believing this is only another proof that he utterly
fails to understand or appreciate the real scope and character of Mr.
Edison's work.

To those familiar not only with Mr. Edison's telephone but with the long
line of experimental investigation that had to be gone through with
before he was able to control the excessive sensitiveness of the
elements of his original discovery, it is very clear that Mr. Hughes has
been working upon and over-estimating the importance of one phase, and
that a limited phase, of Mr. Edison's investigations.

We propose shortly to review at length the evidence of Mr. Edison's
priority in the invention or discovery of all that the microphone
covers; this purely as a question of scientific interest. For the
personal elements of the controversy between Mr. Edison on the one side
and Messrs. Preece and Hughes on the other we care nothing.

       *       *       *       *       *




               =THE SCIENTIFIC AMERICAN EXPORT EDITION.=

The inquiry for American manufactured products and machinery abroad
seems to grow in volume and variety daily. And though, in comparison
with our capacity to produce, the foreign demand is yet small, its
possibilities are unlimited. To increase the demand the immediate
problem is to make known throughout the world in the most attractive
fashion possible the wide range of articles which America is prepared to
furnish, and which other nations have use for. As a medium for conveying
such intelligence the monthly export edition of the SCIENTIFIC AMERICAN
is unequaled. The table of contents of the second issue, to be found in
another column, will give an idea of the wide range and permanent as
well as timely interest of the matter it circulates. It is a magazine of
valuable information that will be preserved and repeatedly read. The
handsomely illustrated advertising pages supplement the text, and make
it at once the freshest, fullest, and most attractive periodical of the
sort in the world. An examination of the index of advertisers will show
how widely its advantages for reaching foreign buyers have been
appreciated by leading American houses. In the advertising page XXV.
appears a list of some eight hundred foreign commercial places in which
the circulation of the paper is guaranteed, as evidence that it reaches
those for whom such publications are intended.

       *       *       *       *       *




                            =FOUNTAIN PENS.=

For several days we have had in use in our office examples of the
Mackinnon Fountain Pen, and find it to be a very serviceable and
effective instrument. This is a handsome looking pen, with a hollow
handle, in which a supply of ink is carried, and the fluid flows from
the point in the act of writing. The necessity of an inkstand is thus
avoided. One of the difficulties heretofore with pens of this character
has been to insure a free and certain delivery of the ink, and also to
bring the instrument within the compass and weight of an ordinary pen.
The inventor seems to have admirably succeeded in the example before us.
The ink flows with certainty, and there is no scratching as with the
ordinary pen; it writes with facility on either smooth or rough paper;
writes even more smoothly than a lead pencil; may be carried in the
pocket; is always ready for use; there is no spilling or blotting of
ink. The construction is simple, durable, and the action effective. One
filling lasts a week or more, according to the extent of use. These are
some of the qualities that our use of the pen so far has seemed to
demonstrate; and which made us think that whoever supplies himself with
a Mackinnon Pen will possess a good thing. The sole agency is at No. 21
Park Row, New York city.

       *       *       *       *       *




                               =THE SUN.=

             BY S. P. LANGLEY, ALLEGHENY OBSERVATORY, PA.*

When, with a powerful telescope, we return to the study of the sun's
surface, we meet a formidable difficulty which our first simple means
did not present. This arises from the nearly constant tremors of our own
atmosphere, through which we have to look. It is not that the tremor
does not exist with the smaller instrument, but now our higher
magnifying power exaggerates it, causes everything to appear unsteady
and blurry, however good the glass, and makes the same kind of trouble
for the eye which we should experience if we tried to read very fine
print across the top of a hot stove, whence columns of tremulous air
were rising. There is no remedy for this, unless it is assiduous
watching and infinite patience, for in almost every day there will come
one or more brief intervals, lasting sometimes minutes, sometimes only
seconds, during which the air seems momentarily tranquil. We must be on
the watch for hours, to seize these favorable moments, and, piecing
together what we have seen in them, in the course of time we obtain such
knowledge of the more curious features of the solar surface as we now
possess.

The eye aches after gazing for a minute steadily at the full moon, and
the sun's light is from 300,000 to 600,000 times brighter than full moon
light, while its heat is in still greater proportion. The object lens of
such a telescope as the equatorial at Allegheny is 13 inches in
diameter, and it is such light, and such heat, concentrated by it, that
we have to gaze on. The best contrivance so far found for diminishing
both, and without which our present acquaintance with the real
appearance and character of sunspots would not have been gained, depends
upon a curious property of light, discovered by a French physicist,
Malus, in the beginning of this century. Let A (Fig. 10) be a piece of
plane unsilvered glass, receiving the solar rays and reflecting them to
a second similar one, B, which itself reflects them again in the
direction C. Of course, since the glass is transparent, most of the rays
will pass through A, and not be reflected. Of those which reach B again
most will pass through, so that not a hundredth part of the original
beam reaches C. This then, is so far a gain; but of itself of little
use, since, such is the solar brilliancy, that even this small fraction
would, to an eye at C, appear blindingly bright. Now, if we rotate B
about the line joining it with A, keeping always the same reflecting
angle with it, it might naturally be supposed that the light would
merely be reflected in a new direction unchanged in quantity.

But according to the curious discovery of Malus this is not what
happens. What does happen is that the second glass, after being given a
quarter turn (though always kept at the same angle), seems to lose its
power of reflection almost altogether. The light which comes from it now
is diminished enormously, and yet nothing is distorted or displaced;
everything is seen correctly if enough light remains to see it by at
all, and the ray is said to have been "polarized by reflection." It
would be out of place to enter here on the cause of the phenomenon; the
fact is certain, and is a very precious one, for the astronomer can now
diminish the sun's light till it is bearable by the weakest eye, without
any distortion of what he is looking at, and without disturbing the
natural tints by colored glasses. In practice, a third and sometimes a
fourth reflector, each of a wedge shaped, optically plane piece of
unsilvered glass, are thus introduced, and by a simple rotation of the
last one the light is graded at pleasure, so that with such an
instrument, called "the polarizing eyepiece" (Fig. A), I have often
watched the sun's magnified image for four or five hours together with
no more distress to the eye than in reading a newspaper.

With this, in favorable moments, we see that the sun's surface away from
the spots, everywhere, is made up of hundreds of thousands of small,
intensely brilliant bodies, that seem to be floating in a gray medium,
which, though itself no doubt very bright, appears dark by comparison.
What these little things are is still uncertain; whatever they are, they
are the immediate principal source of the sun's light and heat. To get
an idea of their size we must resort to some more delicate means of
measurement than we used in the case of the watch. The filar micrometer
consists essentially of two excessively fine strands of cobwebs (or,
rather, of spider's cocoon), called technically "wires," stretched
parallel to each other and placed just at the focus of the telescope.
Suppose one of them to be fixed and the second to be movable (keeping
always parallel to the first) by means of a screw, having perhaps one
hundred threads to the inch, and a large drum shaped head divided into
one hundred equal parts, so that moving this head by one division
carries the second "wire" 1/10000 part of an inch nearer to the first.
Motions smaller than this can clearly be registered, but it will be
evident that everything here really depends upon the accuracy of the
screw. The guide screw of the best lathe is a coarse piece of work by
comparison with "micrometer" screws as now constructed (especially those
for making the "gratings" to be described later), for recent uses of
them demand perhaps the most accurate workmanship of anything in
mechanics--the maker of one which will pass some lately invented tests
is entitled at any rate to call himself "a workman."

[Illustration: Fig. 11]

Since the "wires" are stretched precisely in the focus, where the
principal image of the sun is formed, and move in it, they, and the
features of the surface, form one picture, as magnified by the eye lens,
so that they appear as if moving about on the sun itself. We can first
set them far enough apart, for instance, to take in the whole of a spot,
and then by bringing them together measure its apparent diameter, in ten
thousandths of an inch. Then, measuring the diameter of the whole sun,
we have evidently the proportion that one bears to the other, and hence
the means of easily calculating the real size. A powerful piece of
clockwork, attached to the equatorial, keeps it slowly rotating on its
axis, at the same angular rate as that with which the sun moves in the
sky, so that any spot or other object there will seem to stay fixed with
relation to the "wires," if we choose, all day long. The picture of
"wires," spots, and all, may be projected on a screen if desired; and
Fig. 11 shows the field of view, with the micrometer wires lying across
a "spot," so seen on the 6th of March, 1873. Part of a cambric needle
with the end of a fine thread is represented also as being projected on
the screen along with the "wires" to give a better idea of the delicacy
of the latter.

Now we may measure, if we please, the size of one of those bright
objects, which have just been spoken of as being countable by hundreds
of thousands. These "little things" are then seen to be really of
considerable size, measuring from one to three seconds of arc, so that
(a second of arc here being over 400 miles) the average surface of each
individual of these myriads is found to be considerably larger than
Great Britain. Near the edge of the disk, under favorable circumstances,
they appear to rise up through the obscuring atmosphere, which darkens
the limb, and gathered here and there in groups of hundreds, to form the
white cloudlike patches (_faculæ_), which may sometimes be seen even
with a spy-glass--"something in the sun brighter than the sun itself,"
to employ the expression by which Huyghens described them nearly two
hundred years ago. They are too minute and delicate objects to be
rendered at all in our engraving; but this is true also of much of the
detail to be seen at times in the spots themselves. The wood cuts make
no pretense to do more than give an outline of the more prominent
features, of which we are now about to speak. The wonderful beauty of
some of their details must be taken on trust, from the writer's
imperfect description of what no pencil has ever yet rendered and what
the photograph has not yet seized.

[Illustration: Fig. A.]

[Illustration: Fig. 10.]

Bearing this in mind, let us now suppose that while using the polarizing
eyepiece on the part of the spot distinguished by the little circle, we
have one of those rare opportunities when we can, by the temporary
steadiness of our tremulous atmosphere, use the higher powers of the
telescope and magnify the little circle till it appears as in Fig. 12.
We have now nearly the same view as if we were brought close to the
surface of the sun, and suspended over this part of the spot. All the
faint outer shade, seen in the smaller views (the _penumbra_) is seen to
be made up of long white filaments, twisted into curious ropelike forms,
while the central part is like a great flame, ending in fiery spires.
Over these hang what look like clouds, such as we sometimes see in our
highest sky, but more transparent than the finest lace vail would be,
and having not the "fleecy" look of our clouds, but the appearance of
being filled with almost infinitely delicate threads of light. Perhaps
the best idea of what is so hard to describe, because so unlike anything
on earth, is got by supposing ourselves to look _through_ successive
vails of white lace, filled with flower-like patterns, at some great
body of white flame beyond, while between the spires of the flame and
separating it from the border are depths of shade passing into
blackness. With all this, there is something crystalline about the
appearance, which it is hard to render an idea of--frost-figures on a
window pane may help us as an image, though imperfect. In fact the
intense whiteness of everything is oddly suggestive of something very
cold, rather than very hot, as we know it really. I have had much the
same impression when looking into the open mouth of a puddling furnace
at the lumps of pure white iron, swimming half-melted in the grayer
fluid about them. Here, however, the temperature leaves nothing solid,
nothing liquid even; the iron and other metals of which we know these
spot-forms do in part at least consist are turned into vapor by the
inconceivable heat, and everything we are looking at consists probably
of clouds of such vapor; for it is fluctuating and changing from one
form into another while we look on. Forms as evanescent almost as those
of sunset clouds, and far more beautiful in everything but color, are
shifting before us, and here and there we see, or think we see, in the
sweep of their curves beyond, evidences of mighty whirlwinds (greater by
far than the largest terrestrial cyclone) at work. While we are looking,
and trying to make the most of every moment, our atmosphere grows
tremulous again, the shapes get confused, there is nothing left distinct
but such coarser features as our engraving shows, and the wonderful
sight is over. When we consider that this little portion of the spot we
have been looking at is larger than the North and South American
continents together, and that we could yet see its parts change from
minute to minute, it must be evident that the actual motion must have
been rapid almost beyond conception--a speed of from 20 to 50 miles a
_second_ being commonly observed and sometimes exceeded. (A cannon ball
moves less than ¼ of a mile per second.) I have seen a portion of the
photosphere, or bright general surface of the sun, drawn into a spot,
much as any floating thing would be drawn into a whirlpool, and then,
though it occupied by measurement over 3,000,000 miles in area,
completely break up and change so as to be unrecognizable in less than
twenty minutes.

When we come to discuss the subject of the sun's heat, we shall find
that the temperature of a blast furnace or of the oxyhydrogen blowpipe
is low compared with that which obtains all over such a vast region, and
remembering this, it is evident that its disappearance is a cataclysm of
which the most tremendous volcanic outburst here gives no conception. We
cannot, by any terrestrial comparison, describe it, for we have no
comparison for it in human experience. If we try to picture such an
effect on the earth, we may say in another's words that these solar
whirlwinds are such as, "coming down upon us from the north, would in
thirty seconds after they had crossed the St. Lawrence be in the Gulf of
Mexico, carrying with them the whole surface of the continent in a mass,
not simply of ruin, but of glowing vapor, in which the vapors arising
from the dissolution of the materials composing the cities of Boston,
New York, and Chicago would be mixed in a single indistinguishable
cloud."

These vast cavities then in the sun we call spots are not solid things,
and not properly to be compared even to masses of slag or scoria
swimming on a molten surface. They are rather rents in that bright cloud
surface of the sun which we call the photosphere, and through which we
look down to lower regions. Their shape may be very rudely likened to a
funnel with sides at first slowly sloping (the _penumbra_), and then
suddenly going down into the central darkness (the _umbra_). This
central darkness has itself gradations of shade, and cloud forms may be
seen there obscurely glowing with a reddish tinge far down its depths,
but we never see to any solid bottom, and the hypothesis of a habitable
sun far within the hot surface, suggested by Sir William Herschel, is
now utterly abandoned. We are able now to explain in part that
mysterious feature in the sun's rotation before insisted on, for if the
sun be not a solid or a liquid, but a mass of glowing vapor, it is
evidently possible that one part of it may turn faster than another.
_Why_ it so turns, we repeat, no one knows, but the fact that it does is
now seen to bear the strongest testimony to the probable gaseous form of
the sun throughout its mass--at any rate, to the gaseous or vaporous
nature of everything we see. We must not forget, however, that under
such enormous temperature and pressure as prevail there the conditions
may be--in fact, must be--very different from any familiar to us here,
so that when we speak of "clouds," and use like expressions, we are to
be understood as implying rather an analogy than an exact resemblance.

[Illustration: Fig. 12]

We must expect, with the great advances photography has lately made, to
know more of this part of our subject (which we may call solar
meteorology) at the next spot maximum than ever before, and by that time
it may be hoped that some of the wonderful forms described above so
imperfectly will have been caught for us by the camera.

* For parts 1 and 2 see SCIENTIFIC AMERICAN for July 20 and July 27.

       *       *       *       *       *

IN the notice in our issue for July 27 of a new screw cutting lathe made
by Messrs. Goodnow & Wightman, the address should have been 176
Washington street instead of 128, and the diameter of the tail spindle,
which was given as 5/16, should have been 15/16 inch.

       *       *       *       *       *

THE Olympia (Wyoming Territory) _Standard_ announces that a company has
been formed there to bring ice from a glacier. The deposit covers a
number of acres, is seventy or eighty feet deep, and is supposed to
contain a hundred thousand or more tons, some of which may have been
there as many years. The ice can be cut and sold at one and one half
cents a pound, and by the ship load at five dollars a ton.

       *       *       *       *       *




                    =MECHANICAL PUDDLING IN SWEDEN.=

The accompanying engravings, which we take from _Iron_, give plan and
section of the puddling apparatus invented by Mr. Oestlund, as used at
the Finspong Ironworks. The gas generator, A, is of the common Swedish
type, as used for charcoal. The tube, _k_, conducts the gases into the
refining pot, _a_. This pot has a lining of refinery slag, which is
melted, as the apparatus revolves, to get it to adhere to the sides. The
revolution of the pot, _a_, on its axis, _d_, is effected by the action
of the beveled wheels, _b_ and _b'_, and the pulley, _c_, which takes
from an iron chain the power given off by a turbine. The spindle, _d_,
is supported in the bearings, _e_ and _e', c_ carrying a pair of
trunnions which form the axis of oscillation, and allow the apparatus to
rise or fall, the whole of this mechanism being supported on the plummer
blocks, _f f_. One of the trunnions, _e''_, is prolonged so as to form
the axis of the beveled wheel, _b_, and the pulley, _c_, the latter
sliding along the trunnion so as to put _b_ in or out of gear. The bush,
_e_ is tied by means of the stay, _g'_ to the upper end of the toothed
segment, _g_, the lower extremity of which is connected with the second
bush at the end of the spindle. By means of the pinion, _h_, revolving
on standards, _i i_, and the segmental rack, _g_, the pot can be raised
or lowered without interfering with the action of the beveled wheels.

[Illustration: APPARATUS FOR MECHANICAL PUDDLING.]

The gas from the generator is brought to the mouth of the pot by the
tubes, _k_ and _m_. The air necessary for the combustion of the gas is
brought in by a tube, _l_, branching from the air main, _l''_. The air
tube, _l_, passes into the gas tube and is continued concentrically
within the latter. The gas and air tubes both have joints at _m'_ and
_m''_. By means of the bar, _n_, which has a counterpoise to keep the
moving parts in position, the tubes can be brought from or toward the
mouth of the pot, so as to make it free of access to the workman. With a
key fitting on the stem, _n'_, the tubes can be turned in _m'_, so as to
give the currents of gas and air a more or less oblique direction. To
screen the workmen from the heat of the pot a disk of iron, _o_, lined
with fire clay on the side next the pot, is fitted to the end of the
tubes.

[Illustration: APPARATUS FOR MECHANICAL PUDDLING.]

Before running the metal into the pot, the latter must be heated, to
such a degree that the slag lining is pasty or semi-fluid at its
surface. Generally an hour and a half will be spent in heating with gas
to this point. There should be sufficient live coal in the pot when the
gas is first let in to keep up its combustion; should it be extinguished
by excess of air or gas, it must be relit. As soon as the pot begins to
get red hot the full heat can be put on.

The gas generator is tended in the usual way with the ordinary
precautions. To keep ashes and dust out of the gas tube, lumps of
charcoal are heaped up to the height of the top of the flue. The wind
pressure for the generator was 33 to 41 millimeters of mercury, that of
the wind for the combustion of the gas (at Finspong the blast is not
heated) being only 16½ millimeters. The pressure of the gas in the tube
near the pot was 6.2 millimeters of mercury. The method of working,
viewed chemically, does not sensibly differ from puddling; although
giving as good, perhaps better, results at a much less cost. There are
three principal periods in the operation: 1. The period before boiling.
2. The boiling itself. 3. The end of the boiling, and the formation of
balls. When cast metal is poured into the pot a shovelful or two of
refinery slag is added. The temperature of the bath is thus brought
down; it thickens and boils, the pot revolving at the rate of 30 or 40
revolutions a minute. The metal is worked with a rabble, either to cool
it or to get the slag to incorporate with it, as is done in puddling.
Note must be taken of the temperature of the melted metal and that of
the pot, at the moment of charging, the heat during working being
regulated accordingly by increasing or diminishing the inflow of air
and gas. When circumstances are favorable, boiling begins five minutes
after the metal is run into the pot, and it lasts about ten minutes.

Boiling having begun, the batch swells, the iron forms, granulates, and
seems to cling to the rabble and the sides of the pot. The rotation of
the pot is continued, as well as the working, to separate out parts
which are not yet refined; but no more cold cinder is put in. While
boiling goes on the temperature is regulated so that the pig does not
cling to the side of the pot during a complete revolution, but so that
the particles next the side fall back into the bath when the side comes
uppermost in the revolution. The heat is raised a little when the iron
can be felt by the rabble to be completely refined, when shining lumps
make their appearance in the bath, and the iron begins to cling to the
walls. At the moment, therefore, that the temperature is brought to its
highest point, and the iron begins to agglutinate, the rotation of the
pot should be stopped, and either immediately, or after the delay of a
couple of minutes, it is removed. If the iron does not ball well, it is
not completely refined, and the pot may be started again. If the iron is
firm enough already, the isolated particles are exposed to the hottest
flame possible, the blast being carried to its maximum. The refining is
thus completely finished, and all the particles are agglomerated. The
mobility of the gas tube at _m''_ is of advantage in this operation. It
is sometimes useful to start the pot again to round up the puddled ball,
but it is best if this has been formed with the rabble.

The iron from a charge of 75 kilos. of pig may be divided with advantage
into a couple of balls; a third may be made of the iron separated from
the walls of the pot. To get out the balls the pot is lowered, and the
workmen use tongs, pointed rabble, and hooked bar. If things have gone
well the balls ought to come out soft at a welding heat, filled with
cinder like puddled balls, but a little more resisting and solid under
the hammer. They are forged into bars, and these are at once passed to
the rolls. If nothing hinders the balling and shingling, these
operations will not consume more than fifteen minutes.

       *       *       *       *       *




                       =Photographic Engraving.=

Scamoni's process is as follows: The original drawings are carefully
touched up, so that the whites are as pure and the blacks as intense as
possible, and then the negative is taken in the ordinary way, the plate
being backed in the camera with damp red blotting paper, to prevent
reflection from the camera or back of the plate. The negative is
developed in the ordinary manner, intensified by mercuric chloride, and
varnished. A positive picture is taken in the camera, the negative being
carefully screened from any light coming between it and the lens. This
is intensified by pyrogallic acid, and afterward washed with a pure
water to which a little ammonia has been added. It is then immersed in
mercuric chloride for half an hour, and again intensified with
pyrogallic acid. This is repeated several times. When the intensity of
the lines is considerable, the plate is well washed, treated with
potassium iodide, and finally with ammonia, the image successively
appearing yellow, green, brown, and then violet brown. The plate is then
thoroughly drained, and the image is treated successively with a
solution of platinic chloride, auric chloride, ferrous sulphate, and
finally by pyrogallic acid, which has the property of solidifying the
metallic deposits. The metallic relief thus obtained is dried over a
spirit lamp, and covered with an excessively thin varnish. This varnish,
which is evidently a special preparation, retains sufficient tackiness
to hold powdered graphite on its surface (the bronze powder now used may
be employed instead), which is dusted on in the usual manner. After
giving the plate a border of wax, it is placed in an electrotyping bath,
and a perfect facsimile in intaglio is obtained, from which prints may
be taken in a printing press.

       *       *       *       *       *




                     =A NEW DEEP SEA THERMOMETER.=

Perhaps some of our readers may have seen a description of a form of
thermometer devised by MM. Negretti and Zambra for the purpose of
ascertaining the temperature of the ocean at great depths. This
consisted of a tube bent into the shape of a siphon, which when it had
reached the desired depth was made, by means of an ingenious
arrangement, to pour all the mercury found above a certain point near
the reservoir into the second arm of the siphon. This second arm, which,
like the other, was a capillary tube, carried a scale of divisions on
which might be read the temperature of the depths to which the
instrument had been lowered. This thermometer gave all the results that
might have been expected. The ship Challenger during its polar
expedition had on board a certain number of these instruments. The
report of Capt. G. S. Nares made to the English Admiralty describes all
the benefits that we may hope to reap from a serious study of the
temperature of the ocean at different depths, and not the least of these
are those that pertain to the fishery interest. Notwithstanding the good
results given by this instrument, its inventors have endeavored to
render it still more practical and more within the reach of all by
diminishing the cost of construction, and increasing its compactness.

[Illustration: Fig. 1 Fig. 2 Fig. 3 NEW THERMOMETER FOR OBTAINING THE
TEMPERATURE OF THE OCEAN AT GREAT DEPTHS.]

Fig. 1 represents the thermometer isolated from its case. It is an
ordinary thermometer furnished at A with a little device that M.
Negretti has already made use of in the construction of his larger
instrument, and which allows the liquid to run from the reservoir into
the capillary tube when the temperature rises, without letting it flow
back when it lowers, if moreover the precaution has been taken to
incline the tube slightly, reservoir upward. At B there is a bulge in
the tube in which a certain quantity of mercury may lodge; this bulge is
placed in such a way that the mercury resulting from the dilatation of
the reservoir may come to it and continue its ascension in the capillary
tube when the reservoir is down (the thermometer being vertical), but
cannot get out when the reservoir is upward.

We should add that these thermometers are constructed so as to give the
variations of temperature within determined limits.

The small reservoir, B, is indispensable to the well working of the
apparatus; for in seeking the temperature at a certain depth the
instrument may, on being drawn up, pass through warmer strata, and it is
necessary, therefore, to provide the reservoir with a means of diffusing
the small quantity of mercury resulting from this excess of temperature.
The tube has also a small bulge at its upper extremity at C.

The thermometer is placed in a small wooden case having a double bottom
throughout its length. In this double bottom are placed a certain number
of lead balls that can run from one end of the case to the other, and of
sufficient weight to render the instrument buoyant in sea water. To use
the apparatus, one end of a cord is passed through a hole in the case
under the reservoir of the thermometer, and the other end is tied to the
sounding line at a certain distance from the lead (Fig. 2). While the
line is descending the thermometer will remain reservoir downward (Fig.
2); but when it is again drawn up the thermometer case will take the
position indicated in Fig. 3, and the column of mercury breaking at A
will fall into the capillary tube, the divisions of which, as will be
seen at Fig. 1, are reversed.

As to the thermometer itself, it is important to protect it against the
pressure which becomes so considerable at great depths; to do this the
reservoir is surrounded by an envelope of thick glass about three
quarters full of mercury. The mercury serves to transmit the temperature
to the reservoir, and should the exterior envelope yield to the effects
of pressure, the reservoir proper would not be affected, the mercury not
exactly filling the annular part which surrounds it.

       *       *       *       *       *




                           =New Inventions.=

George E. Palmer, of Cedar Rapids, Iowa, has patented an improved
Ironing Board, on which the garments may be held in stretched state
while being smoothed with the irons, and readily adjusted thereon to any
required degree of tension by a simple attachment.

William B. Rutherford and Joel T. Hawkins, of Rockdale, Texas, have
patented an improved Bale Tie, which is formed of the plate provided
with a longitudinal groove and cross ribs or loops, and having
projections or keys to adapt it to receive and hold the notched ends of
the bale band.

An improvement in Composition Pavements has been patented by John C.
Russell, of Kensington, Eng. This invention relates to the treatment of
peat and spent tan for the manufacture of an improved product or
material suitable for paving roads and other places and for roofing,
etc. The most important steps in making the composition consist in
drying bruised or finely ground peat or spent tan, heating the same _in
vacuo_ to degree of 150° Fah., and adding sulphur and gas tar, gas
pitch, and stearine pitch in the proportions specified, then kneading
the mixture while heated and adding carbonate of lime and furnace slag.

Louis Blanck, of New York city, has patented an improved Safety Brake or
attachment for locomotives and railroad cars, by which the entire train,
either by a collision with another train or by contact with any
obstruction, is first raised from the rails, and then moved in backward
direction for the distance of a few feet, so that all danger of accident
is avoided, and no other sensation than that of a slight rocking motion
exerted. The attachment is constructed so as to admit of being worked by
the engineer from the cab or the locomotive, or, if desired, from any
car of the train.

An improved Evaporating Pan had been patented by Andrew D. Martin, of
Abbeville, La. This invention consists in a tapering sheet metal tank
having transverse partitions and longitudinal tapering flues that extend
through all of the partitions and terminate at the ends of the tank.

Lloyd Arnold, of Galveston, Texas, has patented an improved Bale Tie,
which is formed of a block of iron, with a space or opening running
longitudinally through its breadth from one end nearly to the other, and
having the alternate edges of the two plates thus formed notched, the
notch of the lower plate being square and of a width equal to or a
little greater than the bale band, and the notch of the upper plate
being narrower at its bottom than the bale band, and with its sides
inclined and beveled to an edge, to adapt it to receive and hold the
bale band.

An improved Tie for Letter Packages has been patented by John Mersellis,
of Knowersville, N. Y. The object of this invention is to provide a tie
by means of which letter packages may be quickly and securely fastened
or tied. It consists in a plate apertured to receive one end of the
string and also to receive the hook upon which the tie is hung when not
in use, and having a button and clasp spring for engaging the string in
the process of tying.

Fred P. Hammond, of Aurora, Ill., has patented an improved Inking Pad,
which consists in a novel arrangement of layers of cloth or felt,
chamois skin, oiled silk, and printing roller composition, which enables
a clean impression of the stamp to be made. The pad retains the desired
rounded surface and proper degree of softness, and is easily manipulated
when necessary to replenish the supply of ink.

William J. Clark and Thomas W. Roberts, of Coffeeville, Miss., have
patented an improved Trap for Catching Fish in streams, which will allow
the fish to be conveniently taken out without taking up the trap.

John W. Cooper, of Salem, Ind., is the inventor of an improved Alcohol
Lamp for soldering and similar purposes; and it consists in a reservoir
pivoted in a supporting frame, and provided with two wick tubes, and an
extinguisher secured to a spring support, and capable of closing the
larger wick tube when it is in a vertical position. It has an
independent extinguisher for the smaller wick tube, and is provided with
a novel device for projecting the wick from the larger tube as it is
moved out of a vertical position.

Benjamin Slater, of Attica, N. Y., has invented a simple and effective
device for Renovating Feathers by the combined action of steam and hot
air. It consists of a cylindrical receptacle, partly surrounded by a
steam jacket, and having a hot air box, a perforated bottom, a cover or
damper for the same, and an aperture in the top, to which is fitted a
perforated cover and a close cover.

An improved Blind Fastening has been patented by George Runton and John
Runton, of Hoboken, N. J. This fastening is so constructed as to fasten
the blind or shutter automatically when swung open, and in such a way as
to prevent all rattling or shaking of the blind or shutter from the
action of the wind.

David R. Nichols, of Alexandria Bay, N. Y., has patented an improved
Animal Trap, which is so constructed as to set itself after each animal
has been caught, and leave no trace of the trapped animal to frighten
away those that may come afterward.

William A. Doherty, of Fall River, Mass., has patented an improved Loom
Shuttle Attachment, by which the weaving of bad cloth is prevented, and
in case any false shed is made by any irregularities in the warp, and
that part of the shed carried lower than usual, the attachment is
released and thrown over the spindle point, so as to render it
impossible to draw out the filling from the shuttle, and thus break it
and stop the loom.

Jonas Bowman, of Somerset, O., has patented an improved Vehicle Spring,
which permits of dispensing with side bars, thus taking less space to
turn on, and by which the tilting and pitching motion usual with springs
as heretofore constructed is avoided.

Hiram Unger, of Germantown, O., is the inventor of an improved Gate
Latch, which is so constructed that the gate cannot be opened
accidentally by being lifted or by rebounding of the catch or latch.

Madison Calhoun, of Ocate, Ter. of New Mex., has patented an improved
Hame Fastening, which is not liable to become accidentally unfastened,
and is easily and quickly fastened and unfastened, even with cold or
gloved hands.

       *       *       *       *       *

The Downer well at Corry, Pa., is now down over 1,300 feet, and an oil
bearing sand has been struck of about five feet thickness.

       *       *       *       *       *




[Illustration: "Communications.", in Gothic script.]


                           =Our Patent Law.=

_To the Editor of the Scientific American_:

While I cannot handle this subject with any master talent, nor afford to
devote the time which should be given to so important a subject before
expressing an opinion, yet I can less afford to keep quiet and allow
shrewd avarice to manipulate or titled ignorance to legislate my
property out of existence. "Property! There is no property in patents,"
I often hear said. And how about the invention covered by a patent? Is
that property? A large majority of people may say no, and deny the
justice of a patent law. On the contrary, I, as an inventor, think an
invention is genuine property, and as such should be under the same
protection in common law as all other property, instead of requiring a
special law by which the people magnanimously grant me the privilege for
a short time of using what was never theirs, what they never knew of
until I brought it into existence.

But what is real property, and by what title is it held? Mother earth,
from which we sprung, by which we exist, and to which we return, is,
without question, real estate. How is it obtained; how held? History
answers, By conquest, by subjugation. But these words, conquest and
subjugation, have a more significant meaning than the spoiling of one
people by another; they are the actual price of possession. He who,
toiling, subjugates the soil, is undoubted owner of its production, by
virtue of the highest blessing on record--"By the sweat of thy brow
shalt thou obtain bread." And this principle is so far acknowledged that
the laborer holds a lien on the product of his labor, even though the
property belongs to another.

Mr. A has an unpromising piece of land on which he would like to raise
corn. He analyzes the soil, experiments upon it chemically, reads up on
the properties and components of corn, the effects of fertilizers and
acids upon the soil, and makes himself a fool and laughing-stock
generally among his neighbors because he steps out of the beaten track
by which they have succeeded in making the ground barren. He does not
have much success the first year, and is sympathizingly consoled with "I
told you so." But he perseveres and wins the reputation of being
"visionary" and "as stubborn as a mule." In the meantime he becomes more
familiar with his subject, sees more clearly the requirements of the
case, finds he must post himself more thoroughly in certain branches of
science in order to conduct his experiments, wrestles with this obstacle
and that, and finally discovers a fertilizer based on some natural law
of rotation, and produces a crop of corn never before equaled. Now his
neighbors come out with this very intelligent question, "How did you
happen to think of it?" And they further very condescendingly remark,
"That is a rousing crop; I guess I'll try the same thing myself. How did
you say you mixed the stuff?" This man is the true conqueror. He has
endured privation and scorn, fought obstacles, and in subduing them has
eliminated a new principle in agriculture that is an engine of power to
all generations. Shall his crops be his only reward? Shall they who
laughed him to scorn step into his reward without sharing the labor that
produced it?

This is a simile for thousands of inventions, only that the inventor is
seldom situated to plant the corn on his own land and reap the harvest.
Then which of you will say that he has not a just lien on every man's
crop raised by his process for a per cent of the gains thereby? There is
a bill before Congress favoring a periodical taxation of patents under
the pretext of removing useless patents from the path of later
inventors. Let me show you how one inventor looks at that. My neighbor
has a vacant lot on which he is unable to build; but joined to mine it
would increase the value of my property vastly. Now can't you legislate
that old heap of rubbish into my possession somehow? Of course he is
waiting for the rise of property around him to sell his lot well; but
can't you make that appear unnatural, and that he is a dog in the
manger? It is also said that sharpers get control of old patents and lay
an embargo on legitimate business. I reply, first, no one could be
damaged by the owner of a patent unless he infringed that owner's right;
second, if he does infringe, it shows that said patent is valuable,
otherwise he need not infringe; and if valuable why should not he pay
for it? Mr. B, in the employ of Mr. C, watches the machine he uses, and
spends his leisure hours in working out an improvement, which he patents
and offers to C for sale; but as the invention is useless except as
attached to C's machine, he thinks B can't help himself, and adopts the
improvement without paying for it. When a few years have built up a
great industry, and C is rich from his spoils, B steps in with a few
friends at his back, incorporated especially to make C shell out.

Of course this is bad and ought to be legislated against. If it were not
valuable C need not use it. It is not becoming to the Congress of a
great nation to spend its time in legislating worthless patents out of
existence. All such will die a natural death. And if there is sufficient
worth in any patent to claim your consideration, the inventor is
entitled to its price, whether he waits four years or fifteen for his
pay.

I speak of myself, not as an individual, but as representing in this
letter a class, without whose achievements America, in her proud length
and breadth, could not to-day have been. For the last half of my past
life, over twenty years, I have been an inventor. Schooled in adversity,
accustomed to disappointment, sometimes successful, enjoying no
luxuries but the conquest of obstacles, and often forced to simple
pursuits to keep the pot boiling, yet I expect to spend the rest of my
life inventing, feeling strong in the school of experience, and hoping
for such prosperity as will enable me to work out some of the larger
problems in view.

If those in power would really aid the inventor, let them increase his
facilities for information. Circulate the Patent Office _Gazette_ at one
dollar a year, a nominal subscription to insure _bona fide_ readers, and
pay the balance out of the Patent Office surplus now accumulated. This
both to educate and to save inventors from going over old ground,
bringing more talent up to the standard of to-day. Lessen rather than
increase Patent Office fees. Enable the Commissioner to give the
strictest possible examination on every application for a patent, that
when issued it shall bear a _bona fide_ value, by retaining the most
competent examiners at a salary adequate to keep them. Reduce the
cumbrous machinery of patent litigation to about this text, in two
headings: First, Is plaintiff the first inventor? Allow one month to
find that out. If not disproved in that time, allow it. Second, Does
defendant infringe? Allow one month to decide that. If not proven,
discharge the case, with cost to plaintiff. If proved, cost and damage
to be settled by defendant in thirty days.

The ability of wealthy corporations to absorb with impunity the product
of all talent within their reach, and put off the day of reckoning until
plaintiff is swallowed in cost, is the greatest present discouragement
to inventors. Our patent law is now better than any amendment yet
proposed will leave it. If you must tinker over it, remember all laws
are for protection of the weak. The bulldog does not need law to take
the bone from the spaniel. Just in proportion as you damage the patent
law, you destroy the accomplishments and purpose of my life. Therefore I
have spoken; so could a thousand more.                 W. X. STEVENS.
  East Brookfield, Mass.

       *       *       *       *       *


         =The Edison Carbon Telephone and Hughes' Microphone.=

_To the Editor of the Scientific American_:

Mr. Edison finds a resemblance between his carbon telephone and my
microphone.

I can find none whatever; the microphone in its numerous forms that I
have already made, and varied by many others since, is simply the
embodiment of a discovery I have made, in which I consider the
microphone as the first step to new and perhaps more wonderful
applications.

I have proved that all bodies, solid, liquid, and gaseous, are in a
state of molecular agitation when under the influence of sonorous
vibrations; no matter if it is a piece of board, walls of a house,
street, fields or woods, sea or air, all are in this constant state of
vibration, which simply becomes more evident as the sonorous vibrations
are more powerful. This I have proved by the discovery that when two or
more electrical conducting bodies are placed in contact under very
slight constant pressure, resting on any body whatever, they will of
themselves transform a constant electrical current into an undulatory
current, representing in its exact form the vibrations of the matter on
which it reposes; it requires no complicated arrangement and no special
material, and to most experimenters the three simple iron nails that I
have described form the best and most sensitive microphone. But these
contact points would soon oxidize, so naturally I prefer some conducting
material which will not oxidize.

Mr. Edison's carbon telephone represents the principle of the varying
pressure of a diaphragm or its equivalent on a button of carbon varying
the amount of electricity in accordance with this change of pressure; it
represents no field of discovery, and its uses are restricted to
telephony.

The three nails I have spoken of will not only do all, and that far
better than Edison's carbon telephone in telephony, but has the power of
taking up sounds inaudible to human ears, and rendering them audible, in
fact a true microphone; besides it has the merit of demonstrating the
molecular action which is constantly occurring in all matter under the
influence of sonorous vibrations.

Here we have certainly no resemblance in form, materials, or principles
to Mr. Edison's telephone. The carbon telephone represents a special
material in a special way to a special purpose.

The microphone demonstrates and represents the whole field of nature;
the whole world of matter is suitable to act upon, and the whole of the
electrical conducting materials are suitable to its demonstrations.

The one represents a patentable improvement; the other a discovery too
great and of too wide bearing for any one to be justified in holding it
by patent, and claiming as his own that which belongs to the world's
domain.

  London, July 2, 1878.      D. E. HUGHES.

       *       *       *       *       *




                     =New Industrial Enterprises.=

The increasing wealth of a nation, as well as the profitable and steady
employment of its capital and people, depends upon a continual increase
of the producing power. Whenever there are latent resources undeveloped
or opportunities for establishing the first foundation of an industry,
leading as it will to the originating of hundreds of auxiliary ones, an
unusual effort should be made to bring it into existence. If in the
power of individuals to accomplish, so much the better; if needing an
association with State or national influence, then this association
should be formed. It is incumbent upon individuals that they possess a
sufficient pride in the prosperity of the country to give every possible
attention and assistance to a careful practical demonstration of the
feasibility of all the new industrial enterprises which may be presented
with reasonable assurance of final success.

Not in a great expenditure of money: influence is better than money, and
a potential interest in a new enterprise is often better than capital.
The industrial resources of the United States are by no means worked to
their full capacity. The people by no means make all they consume. The
finer articles of use, and requiring much labor and often the highest
skill, are imported from foreign nations. A premium of $10,000 offered
for an improved method in any known present process of production or
manufacture would be almost sure to be called for.

While America exports $175,000,000 worth of raw cotton annually to be
worked up by other people, is it not possible to so increase the
manufacture in America as to keep the greater part of that raw material
and to export the cloth instead? Is it not practicable to establish
great numbers more of sugar estates in the same tropical climate? Is it
not practicable to lay the foundation of half a dozen beet sugar mills
in the country? To begin the weaving of linen goods, and to teach our
farmers that they may produce all the flax fiber as fast as required? To
start a ramie industry in a small way and teach the process to those who
will engage in it?

Will not our silk men put a velvet industry into operation as a germ
from which a future industry may grow? And we might name a hundred other
lesser enterprises which have hardly name in this country, but every one
of which is needed and will add to the wealth of the people.

       *       *       *       *       *




                 =Replanting and Transplanting Teeth.=

Dr. G. R. Thomas, of Detroit, in the current number of the _Dental
Cosmos_, states that this operation of "replanting" has become so common
with him, and the results so uniformly satisfactory, that he does not
hesitate to perform it on any tooth in the mouth, if the case demands
it; and he finds the cases that demand it, and the number that he
operates upon, continually multiplying.

He makes it a point to examine the end of the roots of nearly all his
cases of abscessed teeth; and a record of more than 150 cases, with but
one loss (and that in the mouth of a man so timid that he utterly
refused to bear the pain which nearly always follows for a few minutes,
therefore necessitating re-extraction), convinces him that the operation
is not only practical, but decidedly beneficial to both patient and
operator. For one sitting is all that he has ever really found necessary
to the full and complete restoration of the case.

In the present article, however, Dr. Thomas states that it is his object
not so much to speak of replanting as of transplanting, which he has
reason to believe is just as practical, so far as the mere re-attachment
is concerned, as is replanting. He details, in illustration, a case in
which he successfully performed the operation; inserting in the mouth of
a gentleman, who had lost a right superior cuspidate, a solid and
healthy tooth that he had removed from a lady's mouth four weeks
previously. He opened into canal and pulp chamber of the tooth, from the
apex of the root only; cut the end off one eighth of an inch (it being
that much too long), reduced the size somewhat in the center of the root
(it being a trifle larger than the root extracted), filled and placed it
in position. He states that the occlusion, shape, and color were
perfect, so much so that several dentists who saw the case were not able
to distinguish the transplanted tooth from the others. The two features
in the case that he calls particular attention to are: first, that
although the tooth had been in his office four weeks, there is to-day no
perceptible change in color; and second, that the re-attachment is as
perfect as though it had been transplanted or replanted the same day of
extraction. The operation was performed about three months ago. Dr.
Thomas knows of but two obstacles in the way of the perfect
practicability of "transplanting:" first, the difficulty of obtaining
the proper teeth at the proper time; and second, the possibility of
inoculation. The latter is the more formidable of the two, and, to
escape the ills that might follow, the greatest caution is necessary.
The first difficulty is more easily gotten over, for it is not necessary
that the tooth transplanted should correspond exactly in shape and size
to the one extracted; if it is too large, it may be carefully reduced;
or if too small, new osseous deposit will supply the deficiency. Neither
is it necessary, as we have seen, that the transplanted tooth should be
a freshly extracted one.

As a demonstration of what modern dental surgery is capable of
performing Dr. Thomas' statements are very interesting; it is doubtful,
however, whether popular prejudice will allow this practice of
"transplanting" to become of much use.

       *       *       *       *       *




                    =American Institute Exhibition.=

For forty-seven years the American Institute of New York has opened its
doors and invited American inventors and manufacturers to exhibit their
productions; and again this year it renews its invitation to all. To
such as wish to reach the capitalist and consumer, they must admit that
New York is the place. For details apply to the General Superintendent
by mail or otherwise.

       *       *       *       *       *

On the 22d of June, cloud bursts occurred in the mountains northeast of
San Buenaventura, Cal., causing the Ventura river to pour down such a
volume of muddy water that the ocean was discolored for a distance of
six miles.

       *       *       *       *       *




                      =THE DISTILLATION OF COAL.=

Bituminous coal, of which there are several varieties, is the best
suited for the production of coal gas. The Newcastle coal is principally
used in the manufacture of London gas. Scotch parrot coal produces a
superior gas, but the coke produced is of inferior quality. Boghead coal
is also used for gas making--in fact, every kind of coal, except
anthracite, may be used for this purpose. The bituminous shale produces
a very good gas, and it is used partly to supply the place of cannel or
parrot coal. As carbon and hydrogen, principally with oxygen, are the
elements from which gas is formed, most substances containing these
elements can be partially converted into gas. And gas has been made from
grease or kitchen waste, oil peat, rosin, and wood, besides coal. A ton
of Newcastle or caking coal yields about 9,000 cubic feet of gas, Scotch
coal about 11,000, English cannel about 10,000, and shale about 7,000,
with illuminating powers in the ratio of about 13, 25, 22, and 36
respectively. The coal is put in retorts, _r_, commonly made of fire
clay and often of cast iron. These retorts are from 6 feet to 9 feet
long, and from 1 foot to 1 foot 8 inches in breadth. They are made like
the letter D, elliptical, cylindrical, or bean shaped. They are built
into an arched oven, and heated by furnaces, _f_, beneath. One, three,
five, seven, or more are built in the same oven. The mouthpieces are of
cast iron, and project outward from the oven, so as to allow ascension
pipes, _a p_, to be fixed, to convey the gas generated from the coal to
the hydraulic main, _h m_. After the coal has been introduced into the
retorts, their mouths are closed with lids luted round the edges with
clay, and kept tight by a screw. The retorts are kept at a bright red
heat. If the temperature be too low, less gas and more tar are produced,
less residue being left; while, should the temperature be too high, the
product is more volatile, more residue remaining. And should the gas
remain for any length of time in contact with the highly heated retort,
it is partially decomposed, carbon being deposited, thereby lessening
the illuminating power, and choking up the retort, and more carbon
disulphide is produced at a high temperature. The object is to maintain
a medium temperature, in order to obtain a better gas having the
greatest illuminating power. In about four or five hours the coal in the
retort will have given off all its gas. The mouth of the retort is
opened, and the coke is raked out into large iron vessels, and
extinguished by water. A fresh charge is immediately introduced by means
of a long scoop in the cherry-red retort, and the door luted to. The
ascension pipes, which convey the gas from the retorts, pass straight up
for a few feet, then turn round, forming an arch, then pass downward
into the hydraulic main, beneath the level of the liquid contained in
it, and bubble up through the liquid into the upper portion of the main.
On commencing the main is half filled with water, but after working some
time, this water is displaced by the fluid products of distillation. In
this way, the opening into each retort is closed, so that a charge can
be withdrawn and replaced without interfering with the action of the
other retorts and pipes. The liquid tar, ammoniacal water, and gas pass
from the end, _e_, of the hydraulic main, down through the pipe, P, and
the liquid falls down into the tar well, T W, while the crude gas goes
on into the chest, C, partially filled with the liquid, so that the
plates, _p p_, from the top dip into it to within a few inches of the
bottom. These dip plates are placed in the chest, so as to separate the
openings into each pair of condensing pipes, _c c_, so that the gas
passing into the chest finds no exit except up _c_{1}, and down
_c_{2}; and there being no dip plate between _c_{2} and _c_{3} it
passes up _c_{3}, and down _c_{4}, and as there is no dip plate to
prevent its progress, it passes up _c_{5}, and down _c_{6}, into the
lime or iron purifiers, L I. The condensers are kept cool by exposure to
the atmosphere, and are often cooled by a stream of water from a tank
above. The gas cools quickly, and liquids passing along with the gas in
a state of vapor are condensed and fall into the chest, and pass by an
overflow pipe into the tar well. The purifier is a cast iron vessel, L
I, containing a number of perforated shelves, _s_{1} _s_{1} _s_{1},
on which slaked lime, to the depth of about 4 inches, or much greater
thickness of iron oxide and sawdust, is placed. The gas passes up
through the shelves, _s s s_, and down through the shelves, _s_{1}
_s_{1} _s_{1}, through the pipe, G, into the gas holder, and from
thence through the pipe, M, to the main pipe. The lime abstracts
carbonic anhydride, sulphureted hydrogen, cyanogen, naphthalin, and a
portion of the ammonia, but not carbon disulphide, which latter may be
absorbed by passing the gas through a solution of sodic hydrate and
plumbic oxide, mixed with sawdust. Gas containing CS{2}, on burning,
produces H{2}SO{4}, which injures books and furniture in rooms.
However, the quantity of CS{2} in gas is generally so minute as to be
practically uninjurious. By a proper regulation of the temperature
during distillation, the quantity produced is infinitesimal. When the
lime is saturated it is removed, and fresh supplied; but the iron, after
use, can be reconverted into oxide by exposure to the atmosphere, and
used repeatedly. When iron is used a separate lime purifier is necessary
to remove carbonic anhydride. The last traces of ammonia are removed
before passing to the gas holder, by passing the gas through dilute
sulphuric acid, or up through the interior of a tower having perforated
shelves covered with coke in small pieces, through which a constant
supply of fresh water percolates. This washing removes some of the more
condensable hydrocarbons, and lessens the illuminating power of the gas.
Before the gas passes from the condensers into the purifiers, it passes
through a kind of pump, termed an exhauster, driven by steam power. This
action relieves the retorts from the pressure of the gas passing through
the hydraulic main, etc. It diminishes the deposit of graphite in the
retorts, and lessens leakage in them, should there be any flaws. It also
has the beneficial effect of producing a gas of a higher illuminating
power, since the relief of pressure in the retorts produces a more
favorable condition of combustion.

[Illustration: THE DISTILLATION OF COAL.]

The following are some of the bodies produced in the manufacture of gas,
namely, acetylene, _g_, the carbonate, _s_, chloride, _s_, cyanide, _s_,
sulphide, _s_, and sulphate, _s_, of ammonium; aniline, _t_, anthracene,
_s_, benzine, _l_, carbonic oxide, _g_, carbonic anhydride, _g_,
carbonic disulphide, _l_, chrysene, _s_, cumene, _l_, cymene, _l_,
ethylene, _g_, hydrogen, _g_, leucoline, _l_, methyl-hydride, _g_,
naphthaline, _s_, nitrogen, _g_, paraffine, _s_, phenylic alcohol, _l_,
picoline, _l_, propene, _g_, quartene, _g_, sulphureted hydrogen, _g_,
toluene, _l_, water, _l_, xylene, _l_, etc.

The most of the above solid and liquid substances, with the letters _s_
and _l_ written after, are removed by cooling the gas in the condensers,
and the gaseous substances marked _g_, that are injurious in the
consumption of the gas, are removed by purification. The impurities in
the gas may consist of ammonic carbonate and sulphide, carbonic
anhydride and disulphide, nitrogen, oxygen, sulphureted hydrogen, and
water in the form of vapor; and acetylene, ethylene, and the vapors of
the acetylene, ethylene, and phenylene series of hydrocarbons are the
illuminating ingredients diluted with carbonic oxide, hydrogen, and
methyl-hydride. The approximate percentage composition of coal gas is:
H, 45.6; Me, 34.8; CO, 6.5; C{2}H{4}, 4; CO{2}, 3.6; N, 2.4;
C{4}H{8}, 2.3; SH{2}, 0.3, etc.--_Hugh Clements in English Mechanic._

       *       *       *       *       *




                    =A Short History of Petroleum.=

The _Lumberman's Gazette_ gives the following short history of
petroleum: The production of petroleum as an article of trade dates from
the 28th of August, 1859, when Colonel Drake, in a well 69½ feet
deep, "struck oil," and coined a phrase that will last as long as the
English language. From that beginning it has increased to an annual
production of 14,500,000 barrels of crude oil. The first export was in
1861, of 27,000 barrels, valued at $1,000,000, and the export of
petroleum in the year 1877 was, in round numbers, $62,000,000. The
annual product of petroleum to-day--crude and refined--is greater in
value than the entire production of iron, and is more than double that
of the anthracite coal of the State of Pennsylvania, and exceeds the
gold and silver product of the whole country. As an article of export it
is fourth, and contests closely for the third rank. Our leading exports
are relatively as follows: Cotton annually from $175,000,000 to
$227,000,000; flour from $69,000,000 to $130,000,000; pork and its
products (bacon, ham and lard) from $57,000,000 to $82,000,000; and
petroleum from $48,000,000 to $62,000,000. The total export of petroleum
from 1861 to and including 1877 (16 years) has been $442,698,968, custom
house valuation. From the best sources of information there are at this
time 10,000 oil wells, producing and drilling, which, at a cost of
$5,000 per well, would make an investment of $50,000,000 in this branch
of the business. Tankage now existing of a capacity of 6,000,000 barrels
cost $2,000,000, and $7,000,000 has been invested in about 2,000 miles
of pipe lines connected with the wells. The entire investment for the
existing oil production, including purchase money of territory, is
something over $100,000,000, which amount cannot be lessened much, if
any, for as wells cease to produce new ones have been constantly drilled
to take their place.

       *       *       *       *       *




                        =Minute Forms of Life.=

The Rev. W. H. Dallinger lately delivered a lecture at the Royal
Institution, descriptive of the recent researches of Dr. Drysdale and
himself. The object of the lecture was mainly to explain the method of
research which had been employed. The first essays of the opticians to
produce "high powers" were, as might be expected, feeble. These powers
amplified, but did not analyze; hence it began to be questioned whether
"one could see more really with a high power than with a moderate one."
And this was true at the time. But it is not so now. The optician has
risen to the emergency, and provided us with powers of great magnifying
capacity which carry an equivalent capacity for analysis. They open up
structure in a wonderful way when rightly used. The lecturer began by
projecting upon the screen the magnified image of a wasp's sting--an
object about the 1-20th of an inch in natural size--and beside it was
placed a piece of the point of a cambric sewing needle of the same
length, magnified to the same extent. The details of the sting were very
delicate and refined, but the minute needle point became riven and torn
and blunt under the powerful analysis of the lens, showing what the
lecturer meant by "magnifying power;" not mere enlargement, but the
bringing out of details infinitely beyond us save through the well made
lens. This was further illustrated by means of the delicate structure of
the _Radiolaria_, and still further by means of a rarely delicate valve
of the diatom known as _N. rhomboides_. With a magnification of 600
diameters no structure of any kind was visible; but by gradually using
1,200, 1,800, and 2,400 diameters, it was made manifest how the ultimate
structure of this organic atom displayed itself.

But this power of analysis was carried still further by means of the
minutest known organic form, _Bacterium termo_. The lecturer had, in
connection with Dr. Drysdale, discovered that the movements of this
marvelously minute living thing were effected by means of a pair of fine
fibers or "flagella." These were so delicate as to be invisible to
everything but the most powerful and specially constructed lenses and
the most delicate retinas. But since this discovery, Dr. Koch, of
Germany, had actually photographed the flagella of much larger bacteria,
such as _Bacillus subtilis_, and expressed his conviction that the whole
group was flagellate. Mr. Dallinger determined then to try to measure
the diameter of this minute _flagellum_ of _B. termo_ that the real
power of magnification in our present lenses might be tested. This was a
most difficult task, but 200 measurements were made with four different
lenses, and the results were for the mean of the first 50 measurements
0·00000489208; for the second, 0·00000488673; for the third,
0·00000488024; for the fourth, 0·00000488200, giving a mean value for
the whole, expressed in vulgar fractions, of the 1/204700 of an inch as
the diameter of the flagellum of _B. termo_.

With such power of analysis it was manifest that immense results might
be expected from a good use of the "highest powers." The proper method
of using them was next dwelt on, and then the apparatus was described,
by means of which a drop of fluid containing any organism that was being
studied might be prevented from evaporating while under the scrutiny of
the most powerful lenses, and for an indefinite length of time. The
importance of studying such organisms in this way--by continuous
observation--was then plainly shown, some of the peculiar inferences of
Dr. Bastian, as to the transmutation of bacteria into monads, and monads
into amoebæ, etc., being explained by discontinuity of observation.

       *       *       *       *       *




                          =Wages in England.=

Consul General Badeau reports that during the past five years wages have
increased gradually about 10 per cent, while the cost of living has
increased about 25 per cent. Clothing is about 30 per cent higher, while
fuel has not risen in price. Agricultural laborers get from $2 to $3 per
week, including beer; building laborers and gardeners from $4.40 to
$5.10 per week; bricklayers, carpenters, masons, and engineers from
$6.80 to $11 per week; cabinetmakers, printers, and jewelers from $8 to
$12.30 per week, although the best marble masons and jewelers receive
$14.75. Bootmakers and tailors get from $4.86 to $7.65 per week, and
bakers from $4.65 to $7.25, with partial board. Women servants are paid
from $70 to $240 per annum. Railway porters and laborers on public works
get from $4.45 to $12 per week. Rents have risen some 30 per cent, and
are, for artisans in London, from $1.20 to $2.40 per week for one or two
rooms.

       *       *       *       *       *




                 =The Treatment of Cancer by Pressure.=

M. Bouchut has recently introduced to the notice of the members of the
Académie des Sciences a cuirasse of vulcanized caoutchouc, which he has
used with success for the treatment of cancerous and other tumors of the
breast. In this country there has been much division of opinion upon the
utility of pressure in the treatment of cancer, some surgeons regarding
it as harmful, or but rarely useful, others attributing to it great
retardation of the rapidity of growth of the tumor, or even cure. The
surgeons of Middlesex Hospital studied it systematically some years ago,
and gave an unfavorable report. The theory of the plan is certainly
good: a neoplasia, like a healthy tissue, is dependent upon its blood
supply for vitality and growth, and complete anæmia causes the death of
a tumor, as it does of a patch of brain substance. It will be remembered
that Mr. Haward last year related at the Clinical Society a case in
point. He ligatured the left lingual artery for a recurrent epithelioma
of the tongue; the tumor sloughed away, and a fortnight before the
patient's death from blood poisoning the tongue was quite healed. In
just the same way ischæmia will impair the vitality and so lessen the
growth of a tumor. The difficulty is rather in the practical application
of this theory. The knowledge that we now possess of the mode of growth
of cancers gives us at least one important indication. If we have to
deal with a neoplasia that grows at the periphery by gradual
infiltration of the surrounding tissues, it is plain that, for pressure
to be useful, it must be applied around the tumor rather than over it,
where, by compressing and obstructing the capillaries, it would cause
overfullness of those at the circumference. It is the periphery of a
cancer that is its active part, and we must, therefore, produce ischæmia
around and not in the tumor. In the application of the treatment this
must be obtained by the careful adjustment of elastic pads or cotton
wool, and as the whole success of the plan depends upon the skill with
which this is done, too much attention cannot be given to it. We cannot
regard pressure as a substitute for removal of a cancer; but in the
frequent cases where this is impracticable it appears to be the best
substitute at present open to the surgeon. M. Bouchut's cuirasse would
seem to be an improvement upon the spring pads and other appliances in
use in this country.--_Lancet._

       *       *       *       *       *




            =NEW CUTTING AND BORING ATTACHMENT FOR LATHES.=

Our engraving represents a useful little machine which is intended for
attachment to lathes. Although it is exceedingly simple it is capable of
performing a great variety of work.

The machine is used in two ways, either by attachment to a rigid
support, as shown in Fig. 1, or by suspending it by a belt, so that it
is capable of universal motion, as shown in Fig. 2.

The supporting frame, A, has three boxes for the spindle, B, and on the
shaft at one side of the middle box there are planing knives, C, on the
opposite side there is a balance wheel, and a pulley for receiving the
driving belt. The spindle, B, extends beyond the ends of the frame, A,
and has at each end a socket for receiving interchangeable cutting and
boring tools. One end of the spindle is externally threaded to receive a
face plate, to which may be attached a disk of wood for receiving
sandpaper for smoothing and polishing wood or metal.

The frame, A, is held to its work by means of handles, A', and the
spindle is driven by a round belt that passes over a suspended pulley,
E, and also over the pulley on the lathe mandrel.

The entire attachment is balanced by a weight, F, attached to a cord
that passes over a fixed pulley, F', to the pulley, E, to which it is
secured by a swivel hook that permits of turning the belt in any
direction. The belt is guided by small pulleys, H, so that the device
may be turned without running the belt from the pulley on the spindle.

Guides, G, are attached to the frame, A, for guiding the material being
operated upon by the planing knives. The frame, A, may be supported by
attachment to an arm, I, at the lower end of the screw-acted follower,
J, which slides in a rigid support, K. The arm, I, has a notched disk
which is engaged by a spring detent which holds the frame at any desired
inclination.

Among the kinds of work that may be done on this machine may be
mentioned shaping and edging, fluting and beading table legs, balusters,
etc.; dovetailing, boring, carving, paneling, shaping or friezing
mouldings, scroll or fret work, inlaying and engraving, blind stile
mortising and blind slat planing. By changing the inclination of the
spindle different varieties of mouldings may be produced by the same
cutter.

The machine may be used as an emery grinder, and it may also be used for
drilling and shaping metals. For further information address Mathew
Rice, Augusta, Ga.

       *       *       *       *       *




                  =Decrease of the New York Rainfall.=

In his report for 1876, Director Draper, of the New York Meteorological
Observatory in Central Park, showed that a careful examination of the
records in his office proved that there had been, in late years, a
change in the rainfall of New York and its vicinity, affecting seriously
its water supply. The decrease had been steady since 1869, previous to
which there had been an increase. In his report for 1877, Mr. Draper
discusses the question whether the change continues, or is likely to
continue, in the same direction, and comes to the conclusion that the
rainfall of New York will, most probably, continue to decrease by
fluctuations for several years to come; also, that the variations are
very nearly the same in the two portions of the year, the division date
being July 1.

       *       *       *       *       *




                           =NEW STEAM VALVE.=

The improved valve shown partly in section in the engraving is designed
for removing the water of condensation from steam pipes, so that dry
steam may be furnished.

[Illustration: SAUNDERS' STEAM VALVE.]

In the engraving, the globe valve, A, is of the usual form, except that
the casing below the valve seat is enlarged, forming a pocket, B, which
communicates through an aperture at the bottom with a small valve, C.

The steam, in passing through the valve, fills the pocket and there
deposits any water that may have condensed from the steam in its passage
through the steam pipe. The increased depth of the lower portion of the
valve prevents siphoning, which takes place in valves of the ordinary
form. The valve, C, is kept slightly open to discharge the water at the
moment it collects in the pocket; the water is thus prevented from
passing onward to the engine or other point of use.

[Illustration: =CUTTING AND BORING ATTACHMENT FOR LATHES.=]

This valve affords a ready means of supplying dry steam to sulphuric
acid chambers. We are informed that by its use a chamber in ordinary
working order will produce acid 3° to 5° Baumé stronger than can be
obtained with ordinary globe valves. Thirty steam pipes, arranged at
different points, are found to deliver into a chamber in the space of
five minutes from 4 to 16 ounces of condense water (according to the
circumstances of distance, temperature of the air, size of pipe, etc.).
These valves, being placed close to the chamber separating all the
condense water, deliver with certainty uniformly dry steam, without the
inconvenience of ordinary steam traps or other expensive appliances.

This valve was patented through the Scientific American Patent Agency,
May 21, 1878. For further particulars address Mr. Joseph Saunders, 975
Third avenue, Brooklyn, N. Y.

       *       *       *       *       *




                       =A Hint from the Mormons.=

Ex-Governor Hendricks, in a recent industrial address, alluded to the
highly prosperous condition of the Mormons as existing previous to the
influx of the Gentiles into Utah, saying that "to the fact that they
produced all they consumed I attribute their wonderful prosperity." This
remark, associated with the prosperity of other communities in different
parts of the country, would suggest the query of "Why the principle
cannot be more largely applied to the whole nation?" Certainly the
resources of the whole country would indicate a much greater diversity
of production, and if there was the same regard for a uniform building
up of our industrial system there would seem to be need of but little
importation, certainly of goods which can be readily made, and which our
people need the labor to produce.

       *       *       *       *       *




                     =New Agricultural Inventions.=

Joseph George, of Springfield, Greene Co., Mo., has patented an improved
form of Cultivator or Shovel Plow, designed to be convertible into
either a single, double, or triple shovel plow as occasion may require.
It consists in two detachable clamping plates, which hold the plow
beams, and their arrangement with respect to the said beams and the
handles of the plow, whereby a single bolt is made to secure the forward
ends of the handles and clamp the plates to hold the plow beams in
place.

Russel O. Bean, of Macedonia, Miss., is the inventor of an improved Seed
Planter for planting cotton and other seeds, and for distributing
fertilizers. The details of the construction of this planter cannot be
explained without engravings.

Rutus Sarlls and Alexander Kelman, of Navasota, Texas, have invented an
improved combined Planter, Cultivator, and Cotton Chopper, which may be
readily adjusted for use in planting seed, cultivating plants, and
chopping cotton to a stand, and is effective and reliable in operation
in either capacity.

William H. Akens, of Penn Line, Pa., is the inventor of an improved
Dropper, for attachment to the finger bar of a reaper, to receive the
grain and deliver it in gavels at the side of the machine, so as to be
out of the way when making the next round. It is so constructed that
when attached to the finger bar of a mower it will convert it into a
harvester.

James Goodheart, of Matawan, N. J., has devised an improved machine for
Distributing Poison upon potato plants to destroy the potato bug. It may
also be used for sowing seeds.

William V. McConnell and Charles M. Dickerson, of Crockett, Texas, have
invented an improved Fruit Picker, having cup-shaped self-opening spring
jaws attached to its handle, and operated by a cord to close upon and
clamp the fruit. It also has a hollow extensible adjustable handle and a
fruit receiver.

       *       *       *       *       *




                             =Quick Work.=

Two years ago a farmer-miller and his wife, at Carrolton, Mo., furnished
some invited guests with bread baked in eight and a quarter minutes from
the time the wheat was standing in the field. This year it was
determined to make still better time. Accordingly elaborate preparations
were made to reap, thrash, grind, and bake the grain with the least
possible loss of time.

In 1 minute 15 seconds the wheat, about a peck, was cut and thrashed,
and put on the back of a swift horse to be carried to the mill, 16 rods
away. In 2 minutes 17 seconds the flour was delivered to Mrs. Lawton,
and in 3m. 55s. from the starting of the reaper the first griddle cake
was done. In 4 minutes 37 seconds from the starting of the reaper, a pan
of biscuits was delivered to the assembled guests.

After that, according to the Carrolton _Democrat_, other pans of
delicious "one minute" biscuits were baked more at leisure, and eagerly
devoured, with the usual accompaniment of boiled ham and speech making.

       *       *       *       *       *




                       =THE RHINOCEROS HORNBILL.=

[Illustration: =THE RHINOCEROS HORNBILL.=]

There are many strange and wonderful forms among the feathered tribes;
but there are, perhaps, none which more astonish the beholder who sees
them for the first time than the group of birds known by the name of
hornbills. They are all distinguished by a very large beak, to which is
added a singular helmet-like appendage, equaling in size the beak itself
in some species, while in others it is so small as to attract but little
notice. On account of the enormous size of the beak and helmet, the bird
appears to be overweighted by the mass of horny substance which it has
to carry, but on closer investigation the whole structure is found to be
singularly light and yet very strong, the whole interior being composed
of numerous honeycombed cells with very thin walls and wide spaces, the
walls being so arranged as to give very great strength when the bill is
used for biting, and with a very slight expenditure of material.

The greatest development of beak and helmet is found in the rhinoceros
hornbill, although there are many others which have these appendages of
great size. The beak varies greatly in proportion to the age of the
individual, the helmet being almost imperceptible when it is first
hatched, and the bill not very striking in dimensions. The beak gains in
size as the bird gains in strength. In the adult the helmet and beak
attain their full proportions. It is said that a wrinkle is added every
year to the number of the furrows found on the bill. The object of the
helmet is obscure, but the probability is that it may aid the bird in
producing the loud roaring cry for which it is so celebrated. The
hornbill is lively and active, leaping from bough to bough with great
lightness, and appearing not to be in the least incommoded by its huge
beak. Its flight is laborious, and when in the air the bird has a habit
of clattering its great mandibles together, which together with the
noise of the wings produces a weird sound. The food of the hornbill
seems to consist of both animal and vegetable matters. We take our
illustration from Wood's "Natural History."

       *       *       *       *       *




                    =Saw Tempering by Natural Gas.=

Beaver Falls, Pa., contains several gas wells at an average depth of
eleven hundred feet, yielding about 100,000 cubic feet of gas every
twenty-four hours. This gas has been introduced into a large saw
tempering furnace at that place in the works of Emerson, Smith & Co. The
furnace is 8 feet wide by 14 feet long. It is said to be a perfect
success, giving a uniform heat, and there being no sulphur or impurity
in the gas the steel is not deteriorated in the operation of heating.

       *       *       *       *       *




            =THE JAPANESE BUILDING AT THE PARIS EXHIBITION.=

[Illustration: =THE JAPANESE BUILDING AT THE PARIS EXHIBITION.=]

Japan, on the terrestrial globe, lies furthest away in that direction
beyond the Far West of America, and beyond the wide Pacific. The
Japanese structure has a simple and solid aspect, resembling the portal
of a half-fortified mansion, with massive timber frames at the sides;
but it is adorned with two handsome porcelain fountains, and each of
these is designed to represent the stump of a tree supporting a shell
into which the water is poured from a large flower. Before entering the
porch a large map of Japan and a plan of the city of Tokio are seen
displayed on the walls to right and left.--_Illustrated London News._

       *       *       *       *       *




            =Machinery for New York State Capitol Building.=

The Buckeye Engine Company of this city have been awarded the contract
for a pair of condensing engines, cylinders 14 inches diameter, stroke
28 inches, for the State Capitol Building at Albany, New York. The
engines will be of the company's usual horizontal type with automatic
cut off, and will be elaborately finished.

       *       *       *       *       *




                     =The Explosiveness of Flour.=

Professors Peck and Peckham, of the University of Minnesota, have been
making an extensive series of experiments to determine the cause of the
recent flour mill explosion at Minneapolis. The substances tested were
coarse and fine bran, material from stone grinding wheat; wheat dust,
from wheat dust house; middlings, general mill dust, dust from middlings
machines, dust from flour dust house (from stones), and flour. When
thrown in a body on a light, all these substances put the light out.
Blown by a bellows into the air surrounding a gas flame, the following
results were obtained:

Coarse bran would not burn. Fine bran and flour dust burn quickly, with
considerable blaze. Middlings burn quicker, but with less flame. All the
other substances burn very quickly, very much like gunpowder.

In all these cases there was a space around the flash where the dust was
not thick enough to ignite from particle to particle; hence it remained
in the air after the explosion. Flour dust, flour middlings, etc., when
mixed with air, thick enough to ignite from particle to particle, and
separated so that each particle is surrounded by air, will unite with
the oxygen in the air, producing a gas at high temperature, which
requires an additional space, hence the bursting.

There is no gas which comes from flour or middlings that is an
explosive; it is the direct combination with the air that produces gas,
requiring additional space. Powerful electric sparks from the electric
machine and from the Leyden jar were passed through the air filled with
dust of the different kinds, but without an explosion in any case. A
platinum wire kept at a white heat by a galvanic battery would not
produce an explosion. The dust would collect upon it and char to black
coals, but would not blaze nor explode.

A piece of glowing charcoal, kept hot by the bellows, would not produce
an explosion when surrounded by dust, but when fanned into a blaze the
explosion followed. A common kerosene lantern, when surrounded by dust
of all degrees of density, would not produce an explosion, but when the
dust was blown into the bottom, through the globe and out of the top, it
would ignite. To explode quickly the dust must be dry. Evidently when an
explosion has been started in a volume of dusty air, loose flour maybe
blown into the air and made a source of danger.

       *       *       *       *       *




                     =New Engineering Inventions.=

Erskine H. Bronson, of Ottawa, Ontario, Canada, has patented an
improvement in Automatic Switches for Railways, which consists in an
arrangement of sliding cams for moving the switch rails, and in treadles
to be operated by the pilot wheels of the locomotive, and in
intermediate mechanism for connecting the treadles with the switch
operating cams, the object being to provide a switch will be operated
by the pilot wheels of the locomotive as it approaches the movable
switch rails.

An improved Refrigerator Car has been patented by Michael Haughey, of St
Louis, Missouri. The object of this invention is to ventilate and cool
railway cars used in the transportation of perishable articles. This car
has a novel ventilator and ice box and is provided with a new form of
non-conducting walls.

       *       *       *       *       *




                         =CROOKED JOURNALISM.=

In the English scientific journal _Engineering_, of June 21, 1878,
appears a six column article on "Edison's Carbon Telephone," illustrated
with ten engravings from Mr. Prescott's recent work on "The Speaking
Telephone, Talking Phonograph, and other novelties." The descriptions of
the cuts, and the rest of the information given, so far as correct,
obviously come from the same source.

So far as correct: unhappily for the honor of scientific journalism, the
writer's desire is plainly not so much to do justice to truth as to
exalt Mr. Hughes at the expense of Mr. Edison. To this end he has
studiously suppressed from Mr. Prescott's description of the carbon
telephone the points which establish Mr. Edison's claim to the prior
invention or discovery of everything involved in Mr. Hughes' microphone,
while he has as studiously dwelt upon those same points as constituting
the peculiar merits of Mr. Hughes' work.

For example, while he uses Fig. 21 of Mr. Prescott's book, he leaves out
the very important little diagram numbered 20. It represents one form of
the apparatus to which Sir William Thomson refers in the letter in which
he says:

"It is certain that at the meeting of the British Association at
Plymouth last September, a method of magnifying sound in an electric
telephone was described as having been invented by Mr. Edison, which was
identical in principle and in some details with that brought forward by
Mr. Hughes."

The figure looks altogether too much like one form of Mr. Hughes'
microphone to allow of its use in an article intended to establish the
novelty of Mr. Hughes' discovery.

The omissions from the text are quite as significant. Under the first
cut used in _Engineering_, Mr. Prescott says: "In the latest form of
transmitter which Mr. Edison has introduced the vibrating diaphragm is
done away with altogether, it having been found that much better results
are obtained when a rigid plate of metal is substituted in its place....
The inflexible plate, of course, merely serves, in consequence of its
comparatively large area, to concentrate a considerable portion of the
sonorous waves upon the small carbon disk or button; a much greater
degree of pressure for any given effort of the speaker is thus brought
to bear on the disk than could be obtained if only its small surface
alone were used."

The _Engineering_ writer coolly suppresses this important statement. He
does worse: he puts in its place the false statement that "the essential
principle of Mr. Edison's transmitter consists in causing a diaphragm,
vibrating under the influence of sonorous vibrations, to vary the
pressure upon, and therefore the resistance of, a piece of carbon," and
so on.

A little further on, while repeating Mr. Edison's account of the
experiments which led to the abandonment of the vibrating diaphragm
(page 226 of Mr. Prescott's book), the _Engineering_ writer drops out
the following remark by Mr. Edison: "I discovered that my principle,
unlike all other acoustical devices for the transmission of speech, did
not require any vibration of the diaphragm--that, in fact, the sound
waves could be transformed into electrical pulsations without the
movement of any intervening mechanism."

Worse yet, in the very face of Mr. Edison's assertion to the
contrary--an assertion which he could not by any possibility have
overlooked--this most unscientific journalist says: "Mr. Edison finds it
necessary to insert a diaphragm in all forms of his apparatus, that
being the mechanical contrivance employed by which sonorous vibrations
are converted into variations of mechanical pressure, and by which
variations in the conductivity of the carbon or other material is
insured.... On the other hand, Mr. Hughes employs no diaphragm at all,
the sonorous vibrations in his apparatus acting directly upon the
conducting material or through whatever solid substance to which they
may be attached."

In this way throughout the offending article, the writer persistently
robs Edison to magnify Hughes, giving credit to Mr. Hughes for exactly
what he has suppressed from Mr. Prescott's book. To insist as he does,
that, because Mr. Edison covers his carbon button with a rigid iron
plate, in his very practical telephone, therefore a vibrating diaphragm
is an essential feature of Mr. Edison's invention, is a very shallow
quibble in the face of Mr. Edison's and Mr. Prescott's statements that
the carbon button acts precisely the same in the absence of such
covering, though not so strongly. Mr. Edison's laboratory records show a
great variety of experiments in which the carbon was talked against
without "any intervening mechanism." In a telephone for popular use,
however, to be held in the hand, turned upside down, talked into,
exposed to dust and the weather, it was obviously necessary to use some
means for holding the carbon in place, and to prevent its sensitiveness
from being destroyed by dirt and the moisture of the breath when in use.
For this purpose a rigid iron partition seemed at once convenient and
durable. It is not in any sense a "vibrating diaphragm."

With a persistence worthy of a better cause, the _Engineering_ writer
returns to the point he seems especially anxious to enforce. Toward the
end of the article he says: "In every instrument described by Mr. Edison
the diaphragm is the ruling genie of the instrument. Professor Hughes,
however, has through his great discovery been enabled to show that
variations of resistance can be imparted to an electrical current not
only without a diaphragm, but with very much better results when no such
accessory is employed."

The animus of all this is only too apparent. Altogether the article is
the most dishonest piece of writing we have ever seen in a scientific
periodical; and although the article appears in the editorial columns of
_Engineering_, we prefer, for the honor of scientific journalism, to
think that the management of that paper was not party to the rascally
act. It is more credible that a gross imposition has been practiced by
some trusted member of the _Engineering_ staff, or by some contributor
whose position seemed to justify the acceptance of his utterances
without any attempt at their verification. It is well known here to
whom, in London, at Mr. Edison's request, Mr. Prescott sent proofs of
the matter abused, together with electros of the cuts used, in
_Engineering_. Accordingly the burden of dishonor lies upon or between a
prominent British official on the one hand, and on the other a journal
which cannot afford to leave the matter unexplained. Whoever is hurt, we
sincerely hope that the fair fame of scientific journalism for candor
and honesty may come off unstained.

       *       *       *       *       *




                      =A More Perfect Production.=

The highest skill in manufacture or in production of any kind is not yet
the prevailing characteristic of American industry. Uniformity of
production, of whatever kind, is of much greater importance than to
attempt the manufacture of any grade for which the material or the
tools, the machinery or the knowledge of the workmen is not fitted. The
highest condition of product in any nation is to produce the finest or
highest cost articles in the most perfect manner, and to have material
and machinery adopted, and the skilled workmen, so as to be able to so
produce economically. But until the master hand is satisfied of all the
requisites for producing fine goods, he should confine production to the
best his facilities will make in the most perfect, uniform manner.

Samples of fine goods are shown all over the country every day, and were
consumers or merchants sure that the product would be the same, there
would be much less difficulty in introducing and more homemade goods
used where now importations are depended upon. The Stevens crash mills
import raw flax because it is to be had according to sample, perfectly
classified, and saves the employment of skilled labor to assort and
classify, and of purchasing a great deal not wanted. The manufacturers
of edge tools and knives use imported steel because it is warranted and
the warrant proves good, while the uncertainty of American steel is such
that a knife will often crack in tempering and cause the loss of labor
worth ten times the difference in the price of the steel. Samples of
alpacas and other dress goods are shown in our jobbing houses fully
equal to any imported goods, but the goods when received are quite often
of various grades and imperfections of character.

The imperfect or second quality productions find sale, but at a much
lower price, and are to be found at second rate places, the
imperfections slight and the goods perhaps generally quite as
serviceable, but not absolutely so, and first class houses, catering to
those who pay highest prices, cannot afford to have any other house
carry better articles than they do. The use of perfect appliances and
the best material and the employment of the highest skill are not yet
the first step and an absolute necessity, as it should be, in America.
The supply of such machinery, material, and labor can be had if those
who propose to enter the production of first class articles will insist
upon it, and if such supplies are appreciated by the payment of their
higher value. The American standard of production is not the highest,
and it can be materially elevated, and while, as at present, too many
common articles are supplied, the leading manufacturers should turn to
producing finer, the finest, and in smaller quantities, to take the
place of many articles now imported, and to supply the new market which
such productions will always create in any country.

       *       *       *       *       *




                    =The Wool Product of the World.=

From an interesting article on the wool trade of the Pacific coast,
published in a recent number of the San Francisco _Journal of Commerce_,
we learn that the number of sheep in the world is now estimated at from
four hundred and eighty-four to six hundred millions, of which the
United States has about 36,000,000, and Great Britain the same number.
From 1801 to 1875 the wool clip of Great Britain and Ireland increased
from 94,000,000 to 325,000,000 pounds. That of France has increased
almost as rapidly, though the wool is finer, as a rule, and hence the
superiority of French cloths. Australia produces nearly as much wool as
the parent country--Great Britain. The United States product increased
from very little at the beginning of the century to about 200,000,000
pounds at the present time. Of this California has produced about one
fourth, and the Pacific coast as a whole almost one third. If the ratio
of growth shown in the past prevails in the future, the day is not far
distant when the Pacific coast will produce at least one half the wool
produced in the United States, as not only California and Oregon, but
also Washington, Idaho, Montana, Utah, and New Mexico are well adapted
to its production. The wool clip of Australia is about 284,000,000
pounds; that of Buenos Ayres and the river Plata, 222,500,000 pounds;
other countries not previously given, 463,000,000 pounds. The total clip
of the world last year was about 1,497,500,000 pounds, worth
$150,000,000. This when scoured would yield about 852,000,000 pounds of
clean wool.

       *       *       *       *       *




                         =Street Main Joints.=

At the annual meeting of the New England Association of Gas Engineers,
Mr. Thomas, of Williamsburg, made the following remarks on this subject:
"In my early experience with the Williamsburg Gaslight Company, with
which I became connected in the year 1854, I found pretty nearly all the
street mains that were laid were connected with cement joints. While
there is no doubt in my own mind that a joint can be made perfectly
tight with cement, I much prefer the lead joint. Another thing to be
taken into consideration to keep tight joints is that the mains should
be laid a sufficient depth under the surface to protect them from the
action of severe frosts. A great many of the mains were not more than 18
inches or 2 feet below the surface of the streets, and at this depth in
our climate it is a matter of impossibility to keep joints tight, as the
action of the frost in winter will displace the mains and cause the
joints to leak. From the bad manner in which our mains were laid, and
the cement joints leaking so much, we could not afford to turn gas on
during the day. Had we done so we should not have had any to supply the
city at night, and we were thus compelled to shut off the gas just as
soon as there was any apology for daylight, and keep it shut off as late
as possible in the evening.

"With the most careful working in this manner, for a period of nine or
twelve months, our losses from leakage amounted to about 52 to 55 per
cent of the gas manufactured. A great part of this loss was caused by
the cement joints leaking, and also a part due to the fact that the
mains were not at sufficient depth under the surface to protect them
from the action of the frost. As soon as we possibly could I went over
the whole of our mains (there was about 17 miles in all), stripping
them, cutting out the cement, and rejointing them with lead. In one
season we got the loss from leakage down to 20 per cent, and this with
the gas turned on during the 24 hours of the day.

"One great objection to cement joints is the rigidity of them; in cases
where pipes have been disturbed by other excavations and settled, I
found in all cases that the mains were broken. In a leading main from
our old works, with cement joints, the main, a 10-inch one, was broken
entirely off and fractured lengthwise besides, by the upheaval of the
ground from frost. In some of the same mains that we had rejointed with
lead the mains were drawn apart, drawing the lead out, but with very
little loss of gas, as the gasket being driven in tight prevented any
great leakage. In cases of this kind the lead was easily driven back,
and the joint made perfectly tight again. I have never in our city put
in any street mains that I have not used lead in the joints, and in
laying mains we always make them gas tight with the gasket used.

"At the present time we have over 90 miles of street mains laid, and
outside of our loss from street lamps (we get paid for three foot
burners and they average about 3¼ foot) our loss from leakage will not
exceed 6 per cent. We have suffered severe loss of gas from sewering in
our city. In some cases where there are railroad tracks in the streets,
the sewers have been run on both sides of the street, alongside and
parallel with our pipes; these excavations are much deeper than our
mains lie, and the earth is always filled in loosely and left to settle.

"In cases of this kind, whole blocks of mains were dragged down, the
pipe broken, and the joints partially pulled apart; at the same time the
leakage from the joints was not so great, the gasket preventing the
leakage. In laying street mains, what you want particularly to attend
to, and especially in the East here, where you have colder weather than
we have (we have not seen much winter until we came on here), is to get
them down under the surface a sufficient depth to protect them from the
frost. With us the least depth is 2 feet 9 inches under the surface of
the street, and I am confident, could our mains remain in the ground as
we put them down, our loss from leakage by them would be very small
indeed. While, as I stated in the beginning, I have no doubt that a
cement joint can be made tight, I can see no benefit in using cement for
the purpose, as I consider lead far superior in accommodating itself to
any upheaval or settling of the earth where the mains are laid down."

       *       *       *       *       *




                      =Successful Shad Hatching.=

Professor J. W. Milner, who has charge of the shad hatching operations
under the direction of the United States Fish Commissioner, Professor
Baird, is now engaged in the preparation of the report of the work for
the season just completed. Speaking of the work on the Atlantic
seaboard, and the distribution of young fish, the report says that at
the Salmon Creek Station, on Albemarle Sound, they obtained 12,730,000
eggs, and turned out 3,000,000 young fish. At the Havre de Grace Station
12,230,000 eggs were obtained, and 9,575,000 young fish were turned out.
About 6,000,000 young shad have been distributed in the rivers emptying
into the Atlantic and Gulf of Mexico during the season. The distribution
of shad during the past season has been carried on on a much larger
scale than in any previous year, and with great success. The restocking
of the rivers of the Atlantic is only the work of a few years.

       *       *       *       *       *




                      =New Use for Lemon Verbena.=

The well known fragrant garden favorite, the sweet-scented or lemon
verbena (_Lippia citriodora_), seems to have other qualities to
recommend it than those of the fragrance for which it is usually
cultivated. The author of a recent work, entitled "Among the Spanish
People," describes it as being systematically gathered in Spain, where
it is regarded as a fine stomachic and cordial. It is used either in the
form of a cold decoction, sweetened, or five or six leaves are put into
a teacup, and hot tea poured upon them. The author says that the flavor
of the tea thus prepared "is simply delicious, and no one who has drunk
his Pekoe with it will ever again drink it without a sprig of lemon
verbena." And he further states that if this be used one need "never
suffer from flatulence, never be made nervous or old-maidish, never have
cholera, diarrhea, or loss of appetite."

       *       *       *       *       *




                   =A VELOCIPEDE FEAT EXTRAORDINARY.=

Two intrepid velocipedists, M. le Baron Emanuel de Graffenried de
Burgenstein, aged twenty years and six months, and a member of the
Society of Velocipede Sport, of Paris, has accomplished, with M. A.
Laumaillé d'Angers, the greatest distance that has been made with a
velocipede in France.

Leaving Paris on March 16, they returned on the 24th of April, after
having traveled a distance of more than three thousand miles.

[Illustration: =A VELOCIPEDE FEAT EXTRAORDINARY.=]

Their route extended through a part of the west, the middle, and the
south of France, Italy, and southern Switzerland. They traveled through
Orléans, Tours, Poitiers, Angoulême, Bordeaux, Montauban, Toulouse,
Montpellier, Marseilles, Toulon, Nice, Menton, San-Remo, Genoa, Turin,
Milan, the Simplon--where they barely escaped destruction by an
avalanche--Vevay, Berne, Lausanne, Geneva, Dijon, Troy, and Provins. The
longest distance that they accomplished in a single day, was between
Turin and Milan, a distance of 90 miles, which they made in 9½ hours.

       *       *       *       *       *




                =Superior Excellence of American Goods.=

The _Post_, of Birmingham, England, remarks with regard to American
competition, that "perhaps the most humiliating feature of the business
for British manufacturers is the fact that their competitors are
prevailing, not through the cheapness, but through the excellence of
their goods. Time was when English workmanship ranked second to none,
and the names of our great manufacturing firms were a guarantee for the
sterling quality of the goods they turned out; but competitions, trades
unions, piece work, short hours, and other incidents of the 'march of
progress' have altered all that. Complaints, received by hardware
merchants from their customers abroad, are not confined to the goods of
second class firms. Manufacturers who have obtained a world-wide
reputation for their products are frequently convicted of sending out
scamped and unfinished work, and they do not venture to deny the
impeachment, pleading only that the most vigilant must be sometimes at
fault, and that their men, unfortunately, are not to be depended upon.
In other cases it is the merchants or their customers who are to blame
for the inferior quality of the articles by cutting prices so low as to
preclude the possibility of honest work, thinking, probably, that
anything is good enough for a foreign or colonial market. But whatever
the cause, the fact is now undeniable, that a great deal of the
manufactured produce shipped from this country of late years has been of
a very low standard, and that the American manufacturers have
consequently had an easy task in beating it."

       *       *       *       *       *




                    =Petroleum Oils as Lubricators.=

Oils from petroleum are now produced suitable for nearly every
mechanical process for which animal oils have heretofore been used, not
excepting those intended for cylinder purposes. A serious objection
attaching to the animal oils is present in petroleum. If, through the
exhaust steam, some of the oil be carried into the boiler, foaming or
priming is the consequence, but the same thing happening in the case of
petroleum is rather a benefit than otherwise, for it not only does not
cause foaming, but it prevents incrustation or adhesion of the scale or
deposit, and this aids in the preservation of the boiler, and is perhaps
the best preventive of the many everywhere suggested.

Often, in removing the cylinder head and the plate covering the valves
of an engine, we see evidences of corrosion or action on the surfaces,
differing entirely from ordinary wear, and the engineer is generally at
a loss how to account for it. According to the general impression grease
or animal oil is the preservative of the metal, and is the last thing
suspected of being the cause of its general disintegration. The reason
of this is that vegetable and animal oils consist of fatty acids, such
as stearic, magaric, oleic, etc. They are combined with glycerin as a
base, and, under ordinary conditions, are neutrals to metals generally,
and on being applied they keep them from rusting by shielding them from
the action of air and moisture. But in the course of time the influence
of the air causes decomposition and oxidation, the oils become rancid,
as it is called, which is acid, and they act on the metals. What happens
at the ordinary temperature slowly goes on rapidly in the steam
cylinder, where a new condition is reached. The oils are subjected to
the heat of high pressure steam, which dissociates or frees these acids
from their base, and in this condition they attack the metal and hence
destroy it.

This applies as well to vegetable as to oils of animal origin, fish or
sperm oil included. Petroleum and oils derived therefrom (generally
called mineral oils) are entirely free from this objection. Petroleum
contains no oxygen, and hence it cannot form an acid, and therefore
cannot attack metal. It is entirely neutral, and so bland that it may be
and is used medicinally as a dressing to wounds and badly abraded
surfaces where cerates of ordinary dressing would give pain.--_Coal
Trade Journal._

       *       *       *       *       *




              =Influence of Light on Plants and Animals.=

Professor Paul Bert, who has recently devoted a great deal of attention
to the study of the influence of light on animals and plants, denies
that the leaves of the sensitive plant close on the approach of evening,
the same as if they had been touched by the hand. On the contrary, he
finds that from 9 in the evening, after drooping, they expand again and
attain the maximum of rigidity at 2 in the morning. What is commonly
called the "sensitiveness" of plants is but the external manifestations
of the influences of light. Professor Bert placed plants in lanterns of
different colored glass; those under the influence of green glass
drooped in the course of a few days as completely as if placed in utter
darkness, proving that green rays are useless, and equal to none at all.
In a few weeks all plants without exception thus treated died. It has
been proved by the experiments of Zimiriareff that the reducing power of
the green matter of plants is proportionate to the quantity of red rays
absorbed, and Bert shows that green glass precisely intercepts these
colored rays, and that plants exist more or less healthily in blue and
violet rays. In the animal world phenomena of a directly opposite nature
are found, and of a more complex character. Here the light acts on the
skin and the movements of the body, either directly or through the
visual organs. M. Pouchet has shown the changes in color that certain
animals undergo, according to the medium in which they live. For
instance, young turbots resting on white sand assume an ashy tint, but
when resting on a black bottom become brown; when deprived of its eyes
the fish exhibits no change of color in its skin; the phenomenon,
therefore, seems to be nervous or optical. Professor Bert placed a piece
of paper with a cut design on the back of a sleeping chameleon; on
bringing a lamp near the animal the skin gradually became brown, and on
removing the paper a well defined image of the pattern appeared. In this
case the light acted directly, and without nervous intervention. If,
however, the eye of the chameleon be extracted, the corresponding side
of the animal becomes insensible to the influence of the light.

Professor Bert's conclusion, therefore, is that the circulation in the
transparent layers of the skin must be affected by light. According to
Dr. Bouchard a sunstroke is the effect of the direct action of light
upon the skin, produced by the blue and violet rays. The heat producing
rays have no part in such accidents, as proved by the fact that workmen
exposed to intense heats do not feel their fatal effect. Professor Bert,
in a series of experiments on a variety of animals, found that none
avoided light, but all rather sought it; and the lowest forms, like the
highest, absorbed the same rays. As regards intensity of color, however,
there was a difference, some being more partial to one ray than another.
Thus the microscopic daphne of the pond preferred yellow; violet was
less in request; spiders seemed to enjoy blue rather than red rays--so
resembling people suffering from color blindness. No two persons are
sensible to the same shades or tones, while absorbing the same light;
and this would seem to indicate that the retina possesses a selective
power.

       *       *       *       *       *




                      =New Mechanical Inventions.=

An improved Weighing Scale has been patented by Hosea Willard, of
Vergennes, Vt. The object of this invention is to economize time in
ascertaining the weight of an article by avoiding the necessity for
shifting the poise on the scale beam. It consists in providing a scale
beam with a number of dishes suspended from different points on said
beam, and representing or corresponding with different weights, so that
the weight of an article may be ascertained by placing it in one or more
of said dishes and observing which dish is depressed.

William John, of Rigdon, Ind., has patented an improved Tire Setting and
Cooling Apparatus, by which the tire may be set by one person, easily
and quickly, without burning the fellies, and without straining the
wheel by the unequal cooling of the tire.

Joseph A. Mumford, of Avondale, Nova Scotia, Canada, has patented an
improved machine for Sawing and Jointing Shingles. This machine cannot
be properly described without engravings. It has an ingenious feeding
device, and its flywheel carries the jointing knives.

       *       *       *       *       *




                       =Ill-balanced Production.=

The Philadelphia _Record_ sensibly remarks that the popular complaint of
over-production is a mistake. Though of a few things we make or mine too
much, our main trouble arises from not producing enough, in variety if
not in quantity.

"The wants of mankind never can be satisfied. Every new means of
supplying a want creates new wants. They grow by what they feed on. As
long as humanity is so constituted, over-production, in a general and
enlarged sense, is impossible. It is this impossible thing with which
the reformers would deal who propose to work fewer hours each day, or
fewer hours in the week. The trouble they deplore does not exist; the
remedy they propose defeats itself. A man cannot get rid of his load by
shifting it from his right hand to his left hand. Production will not be
stopped by making men their own employers certain hours in the day or
certain days in the week, instead of allowing them to pursue their usual
avocations.

"The real trouble, which the labor reformers seem incompetent to fathom,
is that there is not enough diversity in employments. What is desired is
more work in productive enterprises, a more diffused industry, and a
closer commercial connection with those countries wherein we can make
desirable exchanges both of our raw material and our manufactured
products. Every miner that drops his pick and takes up a hoe, every idle
man that turns himself into an earner of wages, every person that picks
up some loose thread of employment, every capitalist that takes
advantage of stagnating industry and cheap material to build a house or
beautify or improve a country seat, or set on foot some new process of
manufacture, does something toward working out the problem which is
puzzling the economists. In good time the surplus iron and coal will be
sold; new populations will want new railroads; recuperated capital will
gather confidence and take hold of new enterprises, and the whole nation
will move forward again to more assured prosperity and to vaster
undertakings."

       *       *       *       *       *




                          =Labor in Germany.=

The consul at Barmen reports that for agricultural labor the pay varies
greatly, according to the proximity to or remoteness from manufacturing
centers; and ranges from fifty-six cents a day in the neighborhood of
Barmen to thirty-one cents a day in the lower Rhine valley, and as low
as eighteen cents in parts of Silesia. At Barmen, Crefeld and
Düsseldorf, carpenters, coppersmiths, plumbers, machinists and
wagonsmiths earn fifty-one to seventy-five cents daily; saddlers and
shoemakers forty-seven to fifty-two cents daily; bakers and brewers,
with board and lodging, from $1.42 to $2.14 weekly, and without board
from sixty cents a day to $4.28 a week; farm hands are paid from $107 to
$215 yearly, with maintenance; railroad laborers from fifty-six to
eighty-three cents per day, and as high as ninety-five cents daily for
piece work on tunnels; silk weavers can earn $2.15 to $2.85 a week per
loom; factory women $2.15, and children $1 a week. Business and wages
are very low. In good times wages are eighty per cent higher. The cost
of the necessaries of life has increased some fifty per cent in thirteen
years, although it is now but little higher than five years ago. A man
and wife with two or three children can live in two or three rooms in a
poor and comfortless manner for $275 a year, and to support such an
establishment all the members have to work ten or twelve hours daily.
For a family of six persons the cost is about $7 per week--an amount but
few families can earn, as the depression of trade and the reduction of
time allow few to do a full week's work, although wages are nominally a
trifle higher than five years ago.

       *       *       *       *       *




                        =Petroleum June Review.=


                         DRILLING WELL ACCOUNT.

The low price of oil and large accumulation of stock in the producing
regions have had the effect to lessen operations in this department
during the month of June.

The total number of drilling wells in all the districts, at the close of
the month, was 266, which was 110 less than in the preceding month. Rigs
erected and being erected 243, against 309 last month. The number of
drilling wells completed during the month was 269, being 151 less than
in May. Aggregate production of the new wells was 3,788 barrels, against
6,851 barrels in May. The total number of dry holes developed in the
month was 22, against 42 in May.

The operators in the great northern field (Bradford district) have
curtailed operations to an extent which will compare favorably with the
operators in the other portions of the producing regions, as will be
seen by the following statement, namely:

Number of wells drilling at the close of the month, 187, against 284 at
the close of the previous month. Number of drilling wells completed in
June, 193, against 346 in May. Number of rigs erected and being erected,
196, against 234 in May.


                              PRODUCTION.

The daily average production for the month was 40,575 barrels, being a
decrease of 227 barrels. The new wells completed in June failed to make
good the falling off of the old ones, by decreasing the daily average
227 barrels. Bradford district shows a daily average production of
16,000 barrels, being an increase of 1,280 barrels over last month.

The aggregate production in June of all the other districts combined,
with the aid of 76 new wells, decreased the daily average 1,507 barrels.


                               SHIPMENTS.

The shipments in June, out of the producing regions, were 174,225
barrels larger than in the preceding month. The total shipments of
crude, and refined reduced to crude equivalent, by railroad, river and
pipes to the following points, were 1,135,119 barrels:

  New York took            555,794 bbls.
  Pittsburg    "           153,182  "
  Cleveland    "           239,389  "
  Philadelphia "            73,426  "
  Boston       "            29,266  "
  Baltimore    "            26,623  "
  Richmond     "             7,000  "
  Ohio River refiners took   5,200  "
  Other local points took   45,239  "
                         ---------
  Total shipments        1,135,119  "

Included in the above shipments there were 140,299 barrels of refined
from Titusville and Oil City, which is equal to 187,065 barrels of
crude.--_Stowell's Petroleum Reporter._

       *       *       *       *       *




                   =Remarkable Poisoning of a Lake.=

A contributor to _Nature_ describes the remarkable poisoning of Lake
Alexandrina--one of the bodies of water which form the estuary of the
Murray river, Australia. This year the water of the river has been
unusually warm and low, and the inflow to the lakes very slight. The
consequence has been an excessive growth of a conferva which is
indigenous to these lakes and confined to them. This alga, _Nodularia
spumigera_, is very light and floats on the water, except during
breezes, when it becomes diffused, and being driven to the lee shores,
forms a thick scum like green oil paint.

This scum, which is from two to six inches thick, and of a pasty
consistency, being swallowed by cattle when drinking, acts poisonously
and rapidly causes death. The symptoms of the poisoning are stupor and
unconsciousness, falling and remaining quiet (as if asleep), unless
touched, when convulsions are induced, the head and neck being drawn
back by a rigid spasm, subsiding before death. The poison causes the
death of sheep in from one to six or eight hours; of horses, in from
eight to twenty-four hours; of dogs, in from four to five hours; and of
pigs in three or four hours. A _post mortem_ shows the plant is rapidly
absorbed into the circulation, where it must act as a ferment, and
causes disorganization. As the cattle will not touch the puddle where
the plant scum has collected and become putrid, all they take is quite
fresh, and the poisoning is therefore not due to drinking a putrescent
fluid full of bacteria, as was suggested.

When the scum collects and dries on the banks it forms a green crust.
When, however, it is left in wet pools it rapidly decomposes, emitting a
most horrible stench, like putrid urine; but previous to reaching this
stage it gives out a smell like that of very rancid butter.

A blue pigment exudes from this decomposing matter, having some
remarkable properties. It is remarkably fluorescent, being red by
reflected and blue by transmitted light; it appears to be a product of
the decomposition, and allied to the coloring matter found in some
lichens.

       *       *       *       *       *




                         =ASTRONOMICAL NOTES.=

                          BY BERLIN H. WRIGHT.

              PENN YAN, N. Y., Saturday, August 10, 1878.

The following calculations are adapted to the latitude of New York city,
and are expressed in true or clock time, being for the date given in the
caption when not otherwise stated.

                                PLANETS.

                          H.M.                                H.M.
  Mercury sets            8 03 eve. |  Saturn Rises           8 89 eve.
  Venus rises             2 42 mo.  |  Saturn in meridian     2 58 mo.
  Jupiter in meridian    10 52 eve. |  Neptune rises         10 27 eve.

                         FIRST MAGNITUDE STARS

                           H.M.                               H.M.
  Alpheratz rises          6 54 eve. |  Regulus sets          7 29 eve.
  Algol (var.) rises       8 34 eve. |  Spica sets            9 24 eve.
  7 stars (Pleiades) rise 10 53 eve. |  Arcturus sets         0 08 mo.
  Aldebaran rises          0 17 mo.  |  Antares sets         11 24 eve.
  Capella rises            9 40 eve. |  Vega in meridian      9 15 eve.
  Rigel Rises              2 23 mo.  |  Altair in meridian   10 27 eve.
  Betelgeuse rises         2 08 mo.  |  Deneb in meridian    11 19 eve.
  Sirius rises             4 24 mo.  |  Fomalhaut rises       9 34 eve.
  Procyon rises            3 59 mo.  |

                                REMARKS

Mercury is brightest this date, and furthest from the sun August 13.
Venus will be at her descending node August 17. Jupiter will be near the
moon August 17, 4h. 20m. morning, being the moon's apparent diameter
north; this will be an occultation south of the equator. Saturn will be
near the moon August 16, being about 7° south.

There will be a partial eclipse of the moon August 16, in the evening.
The moon will rise more or less eclipsed east of Kansas, west of which
no eclipse will be visible.

                        Middle.      End.
                      H.M.          H.M.
  Boston              7 24 eve.     8 50 eve.
  New York            7 12 eve.     8 38 eve.
  Washington          7 00 eve.     8 26 eve.
  Charleston          6 48 eve.     8 14 eve.
  Chicago             ---------     7 44 eve.
  St. Louis           ---------     7 33 eve.
  New Orleans         ---------     7 34 eve.

The following shows the appearance of the moon when the eclipse is
greatest--7·1 digits, or 0·596 of the moon's diameter.

[Illustration]

The size of the eclipse will be the same for all places. The time of
middle and end for any other places may be obtained by applying the
difference of longitude from Washington, converted into time, to the
Washington time of middle and end, adding if east of Washington, and
subtracting if west.

       *       *       *       *       *




               =An Interesting Astronomical Observation.=

_To the Editor of the Scientific American:_

While viewing the planet Jupiter, at about 5 minutes past 10 o'clock
P.M., a very strange sight presented itself to the observers, who were
looking for a transit of one of the satellites. A very dark spot much
larger than a satellite was seen on the eastern edge of the disk, as
shown in the above diagram. It moved rapidly westward along the upper
margin of the northern belt and passed off at 1 o'clock 24 minutes A.M.
(12th). From its first internal contact till its last external contact
was just 3h. 19m., Pittsburg time. It appeared to be a solid opaque
body, truly spherical, very sharply defined, and most intensely black.
The transit of the satellite occurred at 15 minutes after 11 o'clock,
and had no unusual appearance. Now what was that dark body? We are
constant observers of the heavenly bodies, though not deeply versed in
the science of astronomy, and are anxious to know if any one can give us
some light on the subject. The telescopes used were a 2½ inch and 5 inch
achromatic, magnifying 154 and 216 diameters, but the 154 was chiefly
used.                                              JOSEPH WAMPLER.
                                                   JAMES R. GEMMILL.

  McKeesport, Pa., July 11, 1878.

[Illustration]

       *       *       *       *       *




            =Some of Professor Marsh's Recent Discoveries.=

Mr. S. W. Williston, the assistant of Professor Marsh, has been giving
to the Omaha _Bee_ some interesting facts with regard to the great
reptilian fossils recently discovered in Wyoming and Colorado. The bones
found represent reptiles of many sizes, from that of a cat up to one
sixty feet high. The latter, found at Como, Wyoming, belonged to the
crocodile order; but the remains give evidence that the animal stood up
on its hind legs, like a kangaroo. Another found in Colorado is
estimated by Professor Marsh to have been 100 feet long. A great many
remains of the same general class, but belonging to different species,
have been collected and sent East. Among them from three to four hundred
specimens of the dinosaur, and about a thousand pterodactyls, have been
shipped from Colorado, Wyoming, and Kansas. The wings of one of the
latter were from thirty to forty feet from tip to tip. Seventeen
different species of these flying dragons have been found in the chalk
of western Kansas. There have also been found six species of toothed
birds. Comparatively little has been done toward classifying the late
finds, the task is such an enormous one. Great importance is attached to
them, however, since nothing of the kind had been found in America until
a little over a year ago and great stress had been laid by certain
geologists on their absence. Another remarkable feature of the discovery
was that the fossils which had been reported as not existing in this
country had hardly been brought to light in one locality before
thousands of tons of them were simultaneously discovered in half a dozen
different places.

       *       *       *       *       *




      =Trying to Save a Hundred and Fifty Million Dollars a Year.=

Professor Riley, recently appointed Government Entomologist and attached
to the Agricultural Department, reports that specimens of insects
injurious to agriculture are constantly being sent to the department
from all parts of the country, with requests for information. In every
instance, if a proper examination could be made, an effectual remedy
could be found, and not less than $150,000,000 saved to the country
annually. Recently a worm entirely new to science was sent to the
department by an Iowa farmer, whose orchard of several thousand apple
trees had been rendered unproductive for several years by the new
depredator. For the interests of Western fruit growers this insect
should immediately be investigated. Professor Riley asserts that the
$5,000 recently voted by Congress for the investigation of the cotton
worm, which has sometimes damaged the cotton crop of the South as much
as $20,000,000 in a single fortnight, might have been used to better
advantage by the department; the salary of the entomologist will use up
all the money, leaving next to nothing for experiments for the
eradication of the pest.

       *       *       *       *       *




                        =Industrial Education.=

All are agreed that some education is necessary; but what? The great
proportion of those having the direction of our educational system and
facilities in charge still cling to a system which was established long
before the first mechanical operation came into existence. Before the
present system of man's relation to man, socially, industrially,
politically, or commercially, was heard of, and notwithstanding the
revolutions and advancement in all other things, there is a determined
resistance to any attempt at revolution in what shall be considered
education.

There is an effort to establish compulsory education; but what is the
child to be taught? As if in league with the false theories of the
rights of labor, these efforts take the apprentices from the shops,
force them away from where they would learn something, and confine them
inside a school house to learn--what? Certainly nothing of the
materials, or tools, or pursuits by which they are to obtain their
livelihood. The child knows nothing of when or by whom the compass was
discovered, the printing press, the use of powder, electricity, of
steam, or of any one of the thousand mechanical operations now
controlling every department of life. Does any school boy know how many
kingdoms there are in the natural world, or whether an animal, a
vegetable and a mineral all belong to the same or to different ones?
Will he know that from instinct the young of animals seeks its food and
expands its lungs, as by the same instinct the root of a seed sucks up
its nourishment from the soil and sends its leaves up to breathe the
air? Will he know anything of the nature or requirements of the soils or
the plants that grow in them? Will this compulsory education teach the
boy anything of the iron furnace, the foundry or rolling mill, or the
uses or handling of any of their products? Will it teach him anything of
woods and their value, or for what and how they are useful to man?

Will this knowledge, for which the powers of the State are to be
required to force him to know it--will it teach him anything of the
nature or uses of metals, of metal working, or the business depending
upon them? Will it teach him anything of gold or silver, copper or
brass? Anything of pottery, of bone, ivory, celluloid, etc.? Will he
learn anything of hides, leather, or the production of these necessary
articles? Will he know whether the word textile applies to anything but
a spider's web or the wing of a butterfly? Whether the United States
make, import, or grow cotton, wool, silk, flax, and hemp?

Will he know anything of commerce, railroads, telegraphs, printing, and
the great number of clerk labors in the larger towns? Will he have
learned a single thing which will assist him in his work of life? Will
not every boy thus taken out of the shop and placed at the compulsory
schooling find after he has mastered all it has to give him that he yet
knows nothing; that he must then commence where he was and serve his
apprenticeship; that instead of compulsory education his past years have
been wasted in obtaining but a compulsory ignorance?

       *       *       *       *       *




                        =Business and Personal.=

  _The Charge for Insertion under this head is One Dollar a line for
    each insertion; about eight words to a line. Advertisements must be
    received at publication office as early as Thursday morning to
    appear in next issue._

    Lubricene.--A Lubricating Material in the form of a Grease. One
  pound equal to two gallons of sperm oil. R. J. Chard, New York.

    Assays of Ores, Analyses of Minerals, Waters, Commercial Articles,
  etc. Technical formulæ and processes. Laboratory, 33 Park Row, N. Y.
  Fuller & Stillman.

    Manufacturers of Improved Goods who desire to build up a lucrative
  foreign trade, will do well to insert a well displayed advertisement in
  the SCIENTIFIC AMERICAN Export Edition. This paper has a very large
  foreign circulation.

    Cutters, shaped entirely by machinery, for cutting teeth of Gear
  Wheels. Pratt & Whitney Co., Manufacturers, Hartford, Conn.

    18 ft. Steam Yacht, $250. Geo. F. Shedd, Waltham, Mass.

    Electrical instruments of all kinds. One Electric Bell, Battery, Push
  Button, and 50 feet Wire for $4.00. Send for catalogue. H. Thau, 128
  Fulton St., N. Y.

    Wheels and Pinions, heavy and light, remarkably strong and durable.
  Especially suited for sugar mills and similar work. Pittsburgh Steel
  Casting Company, Pittsburgh, Pa.

    Boilers ready for shipment, new and 2d hand. For a good boiler, send
  to Hilles & Jones, Wilmington, Del.

   Best Steam Pipe & Boiler Covering. P. Carey, Dayton, O.

   Foot Lathes, Fret Saws, 6c., 90 pp. E. Brown, Lowell, Ms.

   Sperm Oil, Pure. Wm. F. Nye, New Bedford, Mass.

   Power & Foot Presses, Ferracute Co., Bridgeton, N. J.

    Kreider, Campbell & Co., 1030 Germantown Ave., Phila., Pa.,
  contractors for mills for all kinds of grinding.

    Punching Presses, Drop Hammers, and Dies for working Metals, etc. The
  Stiles & Parker Press Co., Middletown, Conn.

    All kinds of Saws will cut Smooth and True by filing them with our
  New Machine, price $2.50. Illustrated Circular free. E. Roth & Bro.,
  New Oxford, Pa.

    "The Best Mill in the World," for White Lead, Dry, Paste, or Mixed
  Paint, Printing Ink, Chocolate, Paris White, Shoe Blacking, etc.,
  Flour, Meal, Feed, Drugs, Cork, etc. Charles Boss, Jr., Williamsburgh,
  N.Y.

    A Practical Engineer and Machinist, 24 years' experience. Best of
  reference, marine or stationary; forge; fit; repair. W. Barker, 433 2d
  Ave., N. Y.

    Hydraulic Presses and Jacks, new and second hand. Lathes and
  Machinery for Polishing and Buffing metals. E. Lyon & Co., 470 Grand
  St., N. Y.

    Nickel Plating.--A white deposit guaranteed by using our material.
  Condit, Hanson & Van Winkle, Newark, N. J.

    Cheap but Good. The "Roberts Engine," see cut in this paper, June
  1st, 1878. Also horizontal and vertical engines and boilers. E. E.
  Roberts, 107 Liberty St., N. Y.

    The Cameron Steam Pump mounted in Phosphor Bronze is an
  indestructible machine. See ad. back page.

    Presses, Dies, and Tools for working Sheet Metals, etc. Fruit and
  other Can Tools. Bliss & Williams, Brooklyn, N. Y., and Paris
  Exposition, 1878.

    The SCIENTIFIC AMERICAN Export Edition is published monthly, about
  the 15th of each month. Every number comprises most of the plates of
  the four preceding weekly numbers of the SCIENTIFIC AMERICAN, with
  other appropriate contents, business announcements, etc. It forms a
  large and splendid periodical of nearly one hundred quarto pages, each
  number illustrated with about one hundred engravings. It is a complete
  record of American progress in the arts.

    Bound Volumes of the Scientific American.--I will sell bound volumes
  4, 10, 11, 12, 13, 16, 28, and 32, New Series, for $1 each, to be sent
  by express. Address John Edwards, P. O. Box 773, New York.

    For Solid Wrought Iron Beams, etc., see advertisement. Address Union
  Iron Mills, Pittsburgh, Pa., for lithograph, etc.

    Pulverizing Mills for all hard substance and grinding purposes.
  Walker Bros. & Co., 23d and Wood St., Phila.

    2d hand Planers, 7' x 30", $300; 6' x 24", $225; 5' x 24", $200; sc.
  cutt. b'k g'd Lathe, 9' x 28", $200; A. C. Stebbins, Worcester, Mass.

    J. C. Hoadley, Consulting Engineer and Mechanical and Scientific
  Expert, Lawrence, Mass.

    Best Wood Cutting Machinery, of the latest improved kinds, eminently
  superior, manufactured by Bentel, Margedant & Co., Hamilton, Ohio, at
  lowest prices.

    Water Wheels, increased power. O. J. Bollinger, York, Pa.

    We make steel castings from ¼ to 10,000 lbs. weight. 3 times as
  strong as cast iron. 12,000 Crank Shafts of this steel now running and
  proved superior to wrought iron. Circulars and price list free. Address
  Chester Steel Castings Co., Evelina St., Philadelphia, Pa.

    Diamond Saws. J. Dickinson, 64 Nassau St., N. Y.

    Machine Cut Brass Gear Wheels for Models, etc. (new list). Models,
  experimental work, and machine work generally. D. Gilbert & Son, 212
  Chester St., Phila., Pa.

    Holly System of Water Supply and Fire Protection for Cities and
  Villages. See advertisement in Scientific American of last week.

    The only Engine in the market attached to boiler having cold
  bearings. F. F. & A. B. Landis, Lancaster, Pa.

    The Turbine Wheel made by Risdon & Co., Mt. Holly, N. J., gave the
  best results at Centennial tests.

    Hand Fire Engines, Lift and Force Pumps for fire and all other
  purposes. Address Rumsey & Co., Seneca Falls, N. Y., U. S. A.

    For Shafts, Pulleys, or Hangers, call and see stock kept at 79
  Liberty St. Wm. Sellers & Co.

    Wm. Sellers & Co., Phila., have introduced a new Injector, worked by
  a single motion of a lever.

        *       *       *       *       *




                     =NEW BOOKS AND PUBLICATIONS.=

  METALS AND THEIR CHIEF INDUSTRIAL APPLICATIONS. By Charles R. Alder
     Wright. London: Macmillan & Co. 12mo; pp. 191. Price $1.25.

In this neat little volume we have the substance of a course of lectures
delivered at the Royal Institution of Great Britain in 1877, with thirty
or more engraved illustrations of various metallurgical operations. The
author discusses briefly, yet with sufficient fullness for popular
purposes, the principal processes for reducing metals from their ores,
the natural sources of metals, the metallurgy of the different metals,
the physical properties of metals, and their thermic, electric, and
chemical relations. The style is simple and the matter well chosen.

  DOSIA. A Russian Story. Translated from the French of Henry Greville,
     by Mary Neal Sherwood. Boston: Estes & Lauriat. Price $1.50.

This is the seventh of the Cobweb Series of choice fiction, a bright,
wholesome but rather thin story, as befits its associations. Novel
readers will find it an amusing companion for a rainy day in the
country, or for beguiling the tedium of a summer journey.

       *       *       *       *       *




[Illustration: Notes & Queries]

(1) H. P. says: Please inform me of some recipe for removing superfluous
hair. A. Make a strong solution of sulphuret of barium into a paste with
powdered starch. Apply immediately after being mixed and allow to remain
for ten or fifteen minutes. See also p. 107 (8), vol. 38, and p. 25,
current volume.

(2) M. A. C. writes: I would like to know how to dissolve bleached
shellac, to make it a cement for stone. A. Dissolve it by digestion in 3
or 4 parts of strong alcohol, or by the aid of ¼ its weight of borax in
about 4 volumes of boiling water.

(3) A. K. asks: 1. In rating substances as to hardness, diamond being
No. 10, how do aluminum, osmium, iridium and steel as used in steel
pens, number, also common and tempered glass? A. Aluminum about 3,
iridosmine 6.5 to 7, steel 5.5 to 6, glass 5 to 5.5. 2. Can glass 1/32
inch in thickness be ground to angles of 15 per cent or less, and points
as fine as pins, without difficulty, and how? A. No.

(4) D. C. S. asks for a good recipe for cleaning and polishing dirty and
tarnished brass. A. Dip for a short time in strong hot aqueous solution
of caustic alkali, rinse in water, dip for a few moments in nitric acid
diluted with an equal volume of water, rinse again, and finish with
whiting.

(5) C. J. H. asks for the simplest way of producing a coating of the
magnetic or black oxide of iron on iron plates 3 feet x 6 feet. I think
it is called the Barff process. A. See pp. 1041 SCIENTIFIC AMERICAN
SUPPLEMENT, and 232, vol. 36, and 4, vol. 37, of the SCIENTIFIC
AMERICAN.

How can I make tissue paper impervious to air and water, and yet strong
enough to confine gas? A. You may pass the fabric through a solution of
about 1 part caoutchouc in 35 parts of carbonic disulphide, exposing it
then to the air until the solvent has evaporated.

(6) J. H. J. asks how to use hyposulphite (?) of soda to neutralize
chloride of lime in cotton and linen goods after bleaching the same. A.
After washing from it the large excess of the hypochlorite, the fabric
is passed slowly through a solution containing about 10 per cent of the
hyposulphite, and then again thoroughly washed in clean water.

(7) Columbus asks for a recipe for making ink to rule faint lines, such
as he is now writing on. He wants it to rule unit columns in books. A.
Dissolve in a small quantity of warm water 20 parts of Prussian blue by
the aid of 3 parts of potassium ferrocyanide, and dilute the solution
with thin gum water until the proper degree of color is obtained.

(8) A. I. B. asks: Can I add anything to Arnold's writing fluid which
will cause it to give a good free copy in my letter book? A. Try a
little sugar.

(9) R. & C. ask for information in regard to the process of printing
copies of drawings made on transparent materials, by using chemically
prepared paper and exposing to the sunlight. A. It is based on the fact
that an acid in the presence of potassium dichromate strikes a
blackish-green color when brought in contact with aniline. The paper is
prepared by floating it on a bath of aqueous solution of potassium
dichromate and a trace of phosphoric acid, and then drying it in the
dark. Aniline is dissolved in a little alcohol, and the mixed vapors
allowed to come into contact with the sensitive paper that has been
exposed to strong sunlight beneath the drawing, when the portions not
changed by the sunlight assume the dark color mentioned. All that is
requisite is that the paper or cloth original should be fairly
penetrable by the light. A piece of paper sensitized as indicated, a
sheet of glass to place over the drawing, and a box in which to place
the exposed print to the aniline vapor are the only necessary plant.

(10) P. Y. P. writes: 1. To find the number of acres in a farm of valley
and hillside land, is it by measuring the general contour of the land,
allowing its actual surface, or by measuring and allowing only the
imaginary face of the plane of it? A. The latter is the correct method.
2. Can more grain, say rye, be raised on a farm of valley and hillside
land, as described above, than on a farm having a flat surface, the area
of which is equal to the plane of the former, all other things supposed
to be equal? A. No.

(11) Inventor asks: 1. Can you tell me of a book on sound boards? A. We
do not know of a book especially devoted to the subject. 2. Also the
best kind of wood to make them out of? A. Spruce.

(12) F. C. A. writes: I wish to construct a bar electro-magnet to go in
a cylinder 1 inch in diameter and 1 inch long. 1. What size ought the
core to be? What number of wire shall I use, and what number of
Léclanché cells shall I use (not to exceed twelve) to obtain the
greatest possible attractive power, distance 1/10 of an inch? A. Make
the core 3/8 inch, wind it with No. 24 silk covered wire. Use 6 or 8
cells. 2. In the same space, could a horseshoe magnet be used, with a
gain of power over the bar magnet? A. A cylindrical magnet, which is
substantially the same as a horseshoe, might be substituted with
advantage for the bar magnet.

(13) W. C. H. writes: In turning a tapering shaft in an engine lathe,
will the tool if raised above the centers of the lathe turn the taper
true from end to end, _i. e._, neither concave nor convex, the taper to
be made by sliding the tail center the required distance? A. The taper
will be concave.

(14) H. E. H. asks how to make lime light. A. The lime light is made by
directing the jet of an oxyhydrogen blowpipe against a cylinder of lime.
The blowpipe is contrived to take the proper proportion of oxygen and
hydrogen gas, and the lime is placed in the reducing focus of the jet.

(15) L. F. asks: 1. How many Daniell's or Smee's cells would it require
to produce the same effect as 50 Bunsen cells? A. About 100. 2. Is the
diaphragm equally necessary in Bunsen's, Smee's and Daniell's cells, or
can it be omitted in any one of them easier than in the others, and why
so? A. The diaphragm or porous cell is required in Daniell's and
Bunsen's batteries, but is not used in Smee's. The porous cell is used
only in two fluid batteries; its object is to allow the current to pass,
but to prevent the mixture of the two liquids. 3. Is the thickness of
the zinc of any importance? A. Only that the thicker zinc lasts longer.
4. Which is the cheapest way to produce electric sparks and to charge a
Leyden jar, and what will be the expense? A. By means of a frictional
electrical machine. The machines cost from $10 upward.

(16) R. C. K. writes: I am an engineer by trade; have been at it 9
years. Am out of a position at present and want to learn mechanical
draughting. How long would it take me to become a good draughtsman by
taking a special course at some university? And with my knowledge of
engineering and draughting, would my services be likely to be in fair
demand? A. If you are familiar with mechanical operations, you might
become a good draughtsman by close application under a competent
instructor for one or two years. At present there are many excellent
draughtsmen looking for positions.

(17) G. B. M. asks for the cause of the ribs or ridges on the surface of
a piece of timber which has passed through a planing machine. A. They
are frequently due to the intermittent motion of the feed.

(18) A. F. writes: Having a small quantity of gold and gold plated
things, I would like to know the simplest way to melt it. A. Put it in a
small crucible with a little borax and melt in a common kitchen fire.

(19) J. H. S. writes: I have three drawings each 21 x 30 inches, which I
wish to mount upon cloth like a map, placing them end to end so as to
make one whole sheet 90 inches long. The drawings are upon heavy Whatman
paper. A. You should stretch wet canvas or factory cloth upon a frame,
and while it is still damp apply paste to the backs of the drawings and
lay them smoothly on the stretched cloth. When the paste becomes
thoroughly dry cut the cloth from the stretching frame and paste a tape
binding around the edges.

(20) P. M. asks: What is the difference between the inner and outer
rails of a 10° curve 100 yards in length, gauge 4 feet 8 inches? A. If
this 100 yards is measured on the center of the curve, whose radius in
                                             R - 2-1/3
 feet is R, the length of the inner rail is  --------- X 100, and of the
                                                R
            R + 2-1/3
 outer tail --------- X 100.
               R

(21) W. B. K. asks how to make a shoe dressing for ladies' shoes. A.
Soft water, 1 gallon; extract of logwood, 6 ozs.; dissolve at a
temperature of about 120° Fah. Soft water, 1 gallon; borax, 6 ozs.;
shellac, 1½ oz.; boil until dissolved. Potassium dichromate, 3/8 oz.;
hot water, ½ pint; dissolve, and add all together. It is preferred to
add 3 ozs. of strong aqua ammonia to the liquid before bottling.

(22) J. D. asks: What chemicals can be put into water to increase its
efficiency in extinguishing fire? A. Carbonic acid; sodium carbonate.

(23) H. P. writes: Please give me the advantages and disadvantages of
substituting a galvanized iron tube 18 inches in diameter and 20 feet
high for a wood tank, 5 feet wide and 6 deep, as a container of water in
a dwelling house in the country. Would the narrower body of water keep
fresh or sweet longer, etc.? Also the thickness of iron necessary to
safety, and the number of gallons of water this tube would hold. A. The
advantages are in favor of the wooden tank; zinc lined vessels
(galvanized) are unsuitable for reservoirs for potable water. See p.
369, vol. 36, SCIENTIFIC AMERICAN. 0.3 inch iron would be stout enough.
A pipe of the dimensions specified would contain about 327 gallons when
full.

(24) F. L. M. asks: 1. What is the process by which wire is given a
copper finish? A. Clean the wire by pickling it for a short time in very
dilute sulphuric acid and scouring with sand if necessary. Then pass the
clean wire through a strong bath of copper sulphate dissolved in water.
2. Can wire be thus finished and also annealed? If so, how? A. The wire
should be annealed first. 3. What other finish can be put on iron wire
(annealed), and by what process? A. Zinc--by passing the clean wire
through molten zinc covered with sal ammoniac; tin--by drawing the wire
through a bath of molten tin covered with tallow.

MINERALS, ETC.--Specimens have been received from the following
correspondents, and examined, with the results stated:

J. H. McF.--A fine quality of kaolin.--F. C. H.--The floury powder
consists chiefly, if not altogether, of calcium carbonate.--C. L.
G.--They are all silicious limestones. We cannot judge fairly of their
value for building purposes from the powders sent.--D. K.--Ferruginous
earth or marl.--A. E.--It is a partially decomposed feldspar. The white
powder is for the most part an impure, silicious, kaolin.--E. H.--It
consists chiefly of basic carbonate and hydrated oxide of
lead--poisonous.--J. B. V.--It is a fair quality of pipe clay--impure
silicate of alumina--probably worth about $2 per ton in New York.

       *       *       *       *       *




                       =COMMUNICATIONS RECEIVED.=

The Editor of the SCIENTIFIC AMERICAN acknowledges with much pleasure
the receipt of original papers and contributions on the following
subjects:

  Religion.   By W. M. E.
  Cause of Explosion in Flouring Mills.   By G. M.

       *       *       *       *       *




                              [OFFICIAL.]

                          INDEX OF INVENTIONS

                               FOR WHICH

 =Letters Patent of the United States were Granted in the Week Ending=

                            =May 28, 1878,=

                     =AND EACH BEARING THAT DATE.=

               [Those marked (r) are reissued patents.]

A complete copy of any patent in the annexed list, including both the
specifications and drawings, will be furnished from this office for one
dollar. In ordering, please state the number and date of the patent
desired and remit to Munn & Co., 37 Park Row, New York city.

  Acid, recovering waste sulphuric, A. Penissat           204,244
  Axle box slide, car, G. Williams                        204,178
  Axle nut, adjustable, O. B. Thompson                    204,399
  Axles, sand guard for carriage, M. C. Nay               204,164
  Baker and cooker, steam, J. A. McClure                  204,353
  Bale tie, L. Arnold                                     204,183
  Bale tie, Wynkoop & Bloomingdale                        204,409
  Barrel and box, moth-proof, M. L. Thompson              204,263
  Barrel for shipping bottled liquors, S. Strauss         204,259
  Barrel washer, H. Binder                                204,288
  Bed bottom, T. & O. Howe                                204,222
  Bed bottom, G. S. Walker                                204,401
  Bedstead, wardrobe, Hand & Caulier                      204,321
  Bedstead, wardrobe, E. Kiss                             204,340
  Bedstead, invalid attachment for, T. T. Kendrick.       204,232
  Belting, rubber, C. T. Petchell                         204,368
  Bending links, machine for, H. E. Grant                 204,316
  Boiler brooms, operating, A. C. Cock                    204,200
  Boilers, removing sediment from, T. C. Purves           204,250
  Boots and shoes, making, Hurst & Miller                 204,330
  Bottle stopper, H. Martin                               204,350
  Bottle stopper fastener, L. Kutscher                    204,341
  Brake, car, J. Ramsey, Jr.                              204,372
  Brake for railway carriages, R. D. Sanders              204,378
  Brake for railway trains, safety, L. Blanck             204,186
  Brake, horse, I. Spitz                                  204,258
  Brake pipes on cars, coupling, F. A. Sheeley            204,383
  Brake shoe, W. McConway (r)                               8,255
  Brick kiln, E. F. Andrews                               204,182
  Bridge eyes, making, A. Schneiderlochner                204,381
  Bridge, self-adjusting, B. Williams                     204,407
  Buckle, trace, Landon & Decker                          204,342
  Burial apparatus, Patterson & Wheeler                   204,366
  Burial casket, W. Hamilton                              204,320
  Can, fish, bait, and oyster, R. Roney                   204,168
  Can, refrigerating, transportation, W. A. Moore         204,239
  Car coupling, L. Gasser                                 204,313
  Car coupling, C. Gifford                                204,212
  Car coupling, C. A. Roberts                             204,251
  Car, sleeping, A. Jaeger                                204,230
  Cars, dust arrester for railway, A. Clarke              204,134
  Carbureter, gas and air, Dusenbury & Winn               204,413
  Carriage seats, corner iron for, W. B. C. Hershey       204,326
  Carriages, reversible handle for, A. Shoeninger         204,385
  Casting apparatus, J. Duff                              204,307
  Castings, moulding dovetails, Burdick & Easterly        204,129
  Celluloid, etc., core and tube former, J. W. Hyatt      204,227
  Celluloid tubes and hollow articles, J. W. Hyatt        204,228
  Celluloid bar or spring coater, Hyatt & Burroughs       204,229
  Chair, convertible, M. V. Lunger                        204,346
  Chair, invalid, E. C. Jones                             204,231
  Chair, rocking, L. Rausch                               204,373
  Chuck, A. Saunders                                      204,254
  Churn, Barrett & Smith                                  204,124
  Churning apparatus, A. N. Myers                         204,241
  Churning apparatus, J. A. Perry                         204,245
  Clasp for ribbons on rolls, H. G. & C. G. Hubert        204,224
  Clevis, double tree, A. Rosier                          204,252
  Clew line leader, S. R. Brooks                          204,290
  Clock case, G. & D. B. Hills                            204,328
  Clock, repeating, H. Thompson                           204,175
  Clod crusher, C. R. Polen, Sr.                          204,247
  Clothes drier, W. F. Wilson                             204,179
  Clothes pounder, O. Schindler                           204,379
  Cock, stop, G. N. Munger                                204,162
  Cooler, beer, H. F. Schmidt                             204,380
  Corkscrew, A. W. Sperry                                 204,389
  Corn sheller, J. W. Miller                              204,161
  Corpse preserver, Miller & Schneider                    204,237
  Cotton roving can, J. Hill                              204,220
  Cotton worm destroyer, G. Yeager                        204,410
  Cream, apparatus for raising, J. W. Brady               204,127
  Cultivator, J. Young                                    204,412
  Cultivator, harrow, E. Crane (r)                8,260,    8,261
  Cutter, rotary, Mellor & Orum (r)                         8,265
  Cutting board, F. Weed                                  204,176
  Desk, school, J. Edgar                                  204,207
  Draught equalizer, J. Branning                          204,289
  Drilling apparatus, well, J. B. & G. R. Elliote         204,143
  Drilling machine, metal, D. W. Pond                     204,248
  Drills, spring hoe for grain, C. E. Patric              204,365
  Drying kiln, E. T. Gennert                              204,211
  Engine cylinder, steam, G. E. Banner                    204,282
  Engine standard and cylinder, steam, G. E. Banner       204,283
  Engine, wind, H. N. Hill                                204,221
  Engine, wind, Longyear & Clark                          204,345
  Envelope, Shade & Lockwood                              204,256
  Escapement, W. A. Wales                                 204,400
  Excavator and plow, W. M. Smith                         204,387
  Eyeglasses, J. F. Traub                                 204,266
  Fence, hedge, I. O. Childs                              204,197
  Fence, iron, F. R. Martin                               204,236
  Fence post, O. Allen                                    204,275
  Fence post, H. A. Pierce                                204,246
  Fence, wire, W. H. H. Frye                              204,312
  Field roller, T. B. Rice, Jr.                           204,376
  File, newspaper, D. H. King                             204,233
  Fire alarm signal box, R. N. Tooker (r)                   8,267
  Firearm, revolving, B. F. Joslyn               204,334, 204,335
  Firearms, extractor for, B. F. Joslyn          204,336, 204,337
  Fire escape, I. D. Cross                                204,299
  Flour, manufacturing, R. L. Downton                     204,302
  Fruit pitting and cutting machine, C. P. Bowen          204,189
  Fruit pitting machine, A. T. Hatch                      204,217
  Furnace, brass melting, J. Fletcher                     204,309
  Furnace door, P. S. Kemon                               204,339
  Furnace, metallurgic, H. Swindell                       204,392
  Furnace, ore roasting, C. Stetefeldt (r)                  8,266
  Game apparatus, M. Entenmann                            204,208
  Game counter, C. B. Wessmann                            204,404
  Gas, making illuminating, H. W. Adams                   204,181
  Gas burner, W. Anderson                                 204,278
  Gas burners, attachment for, W. W. Batchelder           204,286
  Gas meter, A. C. Blount                                 204,188
  Gas, scintillator for lighting, W. W. Batchelder        204,285
  Glass from lava, making, F. S. Shirley                  204,384
  Globe holder, Bayles & Hunter                           204,184
  Grain binder, G. H. Howe                                204,329
  Grain decorticating apparatus, A. Ames                  204,277
  Grain distributing machine, Fascher & Singer            204,308
  Grinding machine, S. Trethewey                          204,393
  Gun, spring air, A. Pettengill                          204,167
  Harness, E. R. Cahoone                                  204,195
  Harrow, H. F. Wasmund                                   204,268
  Harrow, rotary, E. & E. H. McNiel                       204,354
  Harvester gearing, J. Harris                            204,148
  Hat and cap sweat, J. R. Terry, Jr.                     204,262
  Head protector, F. P. Cummerford                        204,204
  Heaters, draught pipe for, M. A. Shepard                204,170
  Hogs from rooting, preventing, J. M. Stansifer          204,171
  Hoisting device, tobacco, C. F. Johnson                 204,332
  Horse power, Bettis & Heath                             204,185
  Ice, forming sheets of, J. Gamgee                       204,210
  Illuminating fluid, testing, S. S. Mann                 204,235
  Index tag for books, E. M. Capen                        204,196
  Indicator for vessels, roll and pitch, R. Chandler      204,133
  Inkstand, W. P. Speller                                 204,388
  Iron for case hardening, preparing, S. A. Conrad        204,202
  Ironing apparatus, A. K. Brettell                       204,128
  Jewelry, wire trimming for, L. Heckmann                 204,149
  Labeling bottles, E. L. Witte                           204,272
  Ladder, F. A. Copeland                                  204,295
  Ladder, step, J. J. Brady                               204,191
  Lamp, J. S. Butler                                      204,193
  Lamp, E. S. Drake            204,303, 204,304, 204,305, 204,306
  Lamp, F. G. Palmer                                      204,364
  Lamp for cooking, H. S. Fifield                         204,144
  Lantern, C. J. Swedberg                                 204,261
  Lap link, A. Perry                                      204,367
  Lap ring, H. S. Wood                                    204,273
  Latch, gate, H. Unger                                   204,267
  Leather, compound for currying E. S. Thayer             204,398
  Lemon squeezer and shaker, H. L. Heaton                 204,325
  Lifting jack, T. J. Woods                               204,408
  Lightning conductor, H. W. Spang                        204,257
  Lightning rod, D. Munson                                204,359
  Lock, C. C. Dickerman                                   204,139
  Lock, seal, F. G. Hunter                                204,226
  Lock, vehicle seat, D. Kirk                             204,234
  Log turner, C. & F. Strobel                             204,391
  Loom picker, C. T. Grilley                              204,213
  Loom picking mechanism, Terrell & Williams              204,396
  Magnet, multipolar, A. K. Eaton                         204,141
  Manure spreader, J. S. Kemp (r)                           8,254
  Marble, composition for artificial, J. F. Martin        204,348
  Meat chopper, E. W. Fawcett                             204,209
  Meat chopping machine, Meahl & Kwoczalla                204,355
  Military accouterments, C. Harkins                      204,322
  Milking cows, apparatus for, W. F. George               204,314
  Mordants and dyestuffs, S. Cabot, Jr.                   204,130
  Mosquito bar frame, O'Sullivan & Bloom                  204,243
  Mosquito net frame, E. Bloom                            204,187
  Mower, lawn, F. G. Johnson                              204,153
  Mower lawn, A. P. Osborne                               204,242
  Mower, lawn, J. Shaw (r)                                  8,268
  Music box, W. Meissner                                  204,356
  Musical instrument, mechanical, M. J. Matthews          204,352
  Mustache guard, C. H. Barrows                           204,125
  Nut cracker, F. A. Humphrey                             204,225
  Oatmeal machine, G. H. Cormack                          204,137
  Oatmeal machine, D. Oliver                              204,165
  Organ case, L. C. Carpenter                             204,131
  Paddle wheel, A. Wingard                                204,180
  Paddle wheel, aerial, Cowan & Page                      204,296
  Paper and other fabrics, marbleizing G. Grossheim       204,146
  Paper pulp from wood, H. B. Meech (r)       8,256, 8,257, 8,258
  Paper pulp pail, E. Hubbard                             204,223
  Pea nut warmer, F. A. Bowdoin                           204,190
  Pen, fountain, T. H. & J. E. Quinn                      204,371
  Pencil sharpener and eraser, W. Sellers                 204,169
  Pianoforte tuning attachment, H. F. Jacobs              204,152
  Pianofortes, hand guide for, M. Sudderick               204,260
  Pipe, stand, Lewis & Maloney                            204,344
  Planing and sawing wood, W. H. Webb                     204,403
  Planter and plow, corn, D. Hays                         204,218
  Planter, corn, H. Steckler, Jr.                         204,390
  Plow, T. M. Moore                                       204,358
  Plow, F. Nitschmann                                     204,361
  Plow clevis, E. A. Sanders                              204,253
  Pocket for garments, Y. Chow                            204,199
  Pole, carriage, A. R. Bartram (r)                         8,253
  Post office apparatus, G. W. Wiles                      204,270
  Press, cotton, E. L. Morse                              204,240
  Press, cotton, Tate & Curtis                            204,395
  Press, power, J. L. Lewis                               204,158
  Pump, A. S. Baker                                       204,280
  Pumps, machinery for operating, J. W. Hull (r).           8,262
  Punching and beveling metal, J. Morgan (r)                8,251
  Railway gate, C. P. Austin                              204,279
  Railway gate, McCaffrey & Larkin                        204,160
  Railway rail joint, O. Pagen                            204,363
  Refrigerator, R. T. Hambrook                            204,216
  Rein guide, check, A. L. Whitney                        204,269
  Rowlock, I. C. Mayo                                     204,159
  Rubber cutting machine, Ford, Slade, & Baylies          204,145
  Rule, lumber, A. J. Colburn                             204,293
  Sad iron stand, K. E. Keeler                            204,338
  Sash balance and lock, Rayner & Burr                    204,374
  Saw, R. E. Poindexter                                   204,369
  Saw mill carriage, M. Taplin                            204,394
  Saw mill head block, Brett & Perry                      204,192
  Saw sharpener, W. M. Watson                             204,402
  Scale beam, J. Weeks                                    204,177
  Scintillator for lighting cord, W. W. Batchelder        204,284
  Scraper, earth, J. H. Edmondson                         204,142
  Screen, G. F. Halley                                    204,147
  Screen, window, G. L. Reynolds                          204,375
  Scythe snath fastening, M. Hewitt                       204,327
  Seed and fertilizer distributer, W. Harper              204,323
  Seed distributer, J. W. Dooley                          204,301
  Sewer trap, J. M. Thatcher                              204,397
  Sewer trap valve, P. J. Convery                         204,135
  Sewing machine needle bar, Cook & Hill                  204,294
  Sewing machine mechanism, E. Brosemann _et al._         204,291
  Sewing machine table, S. Hill                           204,219
  Sewing machine table, T. Lanston                        204,157
  Sheet metal vessels, handle for, F. Grosjean            204,319
  Shipping case, J. H. Byrne                              204,194
  Shoetip, H. White (r)                                     8,263
  Shoes, rack for holding, etc., J. Priest                204,249
  Shot, tin plated, L. Crooke                             204,298
  Shovels, manufacture of, H. M. Myers                    204,163
  Sink, kitchen, M. W. Scannell                           204,255
  Slate, apparatus for grinding, etc., J. W. Hyatt.       204,151
  Snuff package, B. F. Weyman (r)                           8,264
  Soldering square cans, R. Gornall                       204,315
  Spectacle frame, J. F. Traub                            204,265
  Spinning mules, building rail for, Ogden & Garrett      204,362
  Spinning mules, mechanism for, G. Gurney                204,214
  Spring, door, O. Seely                                  204,382
  Spring, vehicle, N. Nilson                              204,360
  Sprinkler, J. M. Josias                                 204,333
  Sprinklers, inlet pipe for street, G. H. Stallman       204,172
  Steam generator, Collinge & Savage                      204,201
  Steam generator, M. Cullen                              204,203
  Steam superheater, W. Standing                          204,173
  Stone sawing machine, Jennings & Robellaz               204,331
  Stove damper, T. White                                  204,406
  Stove for burning crude, etc., oils, P. Martin          204,349
  Stoves, fire pot lining for, R. J. King                 204,155
  Sulphur, apparatus for refining, H. H. Eames            204,206
  Suspender ends, E. Painter                              204,166
  Table, S. Bobbins                                       204,377
  Tablet, writing, W. O. Davis                            204,138
  Tanks, etc., movable hopper, F. C. Prindle              204,370
  Target, spherical, S. A. Darrach                        204,300
  Tea and coffee pots, knob for, W. B. Choate             204,198
  Telegraph repeater, F. Catlin                           204,132
  Thrashers, clover huller attachment for, J. Allonas     204,276
  Ticket, railway coupon, C. J. Stromberg                 204,174
  Tile for fireproof buildings, bridge, M. F. Lyons       204,347
  Tin, coating lead articles with, J. J. & L. Crooke      204,297
  Tire setter, J. A. Miles                                204,238
  Tire upsetter M. W. Griffiths                           204,317
  Toy pistol, A. F. Able                                  204,123
  Toy pistol, H. J. P. Whipple                            204,405
  Trace, etc., tug coupling, Hazlewood, Jr., & Reagin     204,324
  Track clearer, A. Day                                   204,205
  Truck shifting apparatus, car, R. H. Ramsey (r)           8,259
  Truss, hernial, Banks & Merck                           204,281
  Tubing, manufacture of metal, B. C. Converse            204,136
  Valve gear for engines, L. C. Mason                     204,351
  Vehicle running gear, P. Letalle                        204,343
  Vehicle, side bar, J. Kauffman                          204,154
  Vehicles, spring seat for, J. T. Yerkes                 204,411
  Velocipede, H. A. Reynolds (r)                            8,252
  Ventilator, S. S. Thompson                              204,264
  Ventilator valve, railway car, E. H. Winchell           204,271
  Warming, etc., buildings, apparatus for, L. Bennet      204,126
  Wash board, F. Kueny                                    204,156
  Wash boiler, A. Friedley                                204,311
  Wash stands, water closets, cover for, F. Grosjean      204,318
  Washing machine, E. S. M. Ford                          204,310
  Watch regulator, G. Bichsel                             204,287
  Watch winding device, B. Wormelle                       204,274
  Watches, winding click for, C. T. Higginbotham          204,150
  Water meter, piston, T. Melling                         204,357
  Water wheel, W. S. Clay                                 204,292
  Weather strip, D. Austin                                204,122
  Whip socket and rein holder, B. J. Downing              204,140
  Wrench, Sievers & Winkler                               204,386
  Wringer, mop, W. Haas                                   204,215

       *       *       *       *       *




                              TRADE MARKS.

  Baking powder, Carter Brothers & Co.                      6,136
  Cigars, Foxen, Newman & Co.                               6,132
  Cigars, J. Hirsch                                         6,142
  Cigars, Oliver & Robinson                                 6,150
  Cigars, B. F. Weyman                                      6,154
  Cigars, J. & A. Frey                                      6,156
  Cigars, J. Martinez                                       6,161
  Cigars, cigarettes, etc., Straiten & Storm                6,144
  Cigars, cigarettes, etc., E. A. Smith                     6,145
  Cigars, cigarettes, etc., C. Swartz & Co.                 6,152
  Cigars, cigarettes, etc., I. Underdorfer                  6,158
  Cigarettes, Seidenberg & Co                               6,135
  Cheese, G. S. Hart                                        6,133
  Copying paper and books, W. Mann                          6,159
  Cotton fabrics, Hamilton Manufacturing Company            6,141
  Cotton goods, Nashua Manufacturing Company                6,162
  Dry goods, The Eddystone Manuf. Company                   6,157
  Illuminating oils, Wadsworth, Martinez & Longman          6,163
  Knitted undershirts, etc., Dunham Hosiery Co.             6,155
  Ladies' corsets, C. A. Griswold                           6,139
  Lemonade compound, Abrams & Carroll                       6,147
  Liquid paints, G. W. Pitkin & Co.                         6,151
  Overalls, jumpers, etc., B. Greenebaum                    6,138
  Perforated plasters, Holman Liver Pad Company             6,140
  Pile ointment, G. W. Frazier                              6,149
  Plug tobacco, B. F. Weyman                                6,148
  Prepared skins for beer, C. Maegerlein & Son              6,134
  Saleratus, soda, etc, H. A. De Land & Co.                 6,137
  Smoking, etc., tobacco, Marburg Brothers                  6,143
  Snuff, B. F. Weyman                                6,146, 6,153
  Soap, Ecker & Co.                                         6,160
  Weighing scales, E. & T. Fairbanks & Co.                  6,131

       *       *       *       *       *




                                DESIGNS.

  Buckle, F. Crane                                         10,704
  Fancy cassimere, F. S. Bosworth                10,692 to 10,702
  Handkerchief, J. Grimshaw                                10,703

       *       *       *       *       *




                 =English Patents Issued to Americans.=

                   From June 28 to July 2, inclusive.

  Bale tie.--S. H. Gilman, New Orleans, La.
  Blast furnace.--J. F. Bennett, Pittsburg, Pa.
  Cigarette machine.--V. L'Eplattinaire, N. Y. city.
  Furnace for steam boilers.--O. Marland, Boston, Mass.
  Grain binders.--C. H. McCormick, Chicago, Ill.
  Grain separators.--Barnard & Leas Manufacturing Co., Moline, Ill.
  Mortising chisel.--A. J. Buttler, New Brunswick, N.J.
  Paper making machinery.--J. H. & G. Hatch, South Meriden, Conn.
  Paper vessels or receptacles.--R. B. Crane, N. Y. city.
  Skates.--P. C. Franke, St. Paul, Minn.
  Teeth cleaner.--A. P. Merrill, N. Y. city.
  Timber joining machine.--W. E. Brock. N. Y. city.
  Wearing apparel.--Israel Crane, N. Y. city.

       *       *       *       *       *




                       =The Scientific American=

                           =EXPORT EDITION.=

                           PUBLISHED MONTHLY.

THE SCIENTIFIC AMERICAN Export Edition is a large and SPLENDID
PERIODICAL, issued once a month, forming a complete and interesting
Monthly Record of all Progress in Science and the Useful Arts throughout
the World. Each number contains about ONE HUNDRED LARGE QUARTO PAGES,
profusely illustrated, embracing:

(1.) Most of the plates and pages of the four preceding weekly issues of
the SCIENTIFIC AMERICAN, with its SPLENDID ENGRAVINGS AND VALUABLE
INFORMATION.

(2.) Commercial, Trade, and Manufacturing announcements of leading
houses.

Terms for Export Edition, $5.00 a year, sent prepaid to any part of the
world. Single copies, 50 cents.

For sale at this office. To be had at all News and Book Stores
throughout the country.

       *       *       *       *       *




                              =NOW READY.=

SCIENTIFIC AMERICAN for July, 1878, with Eighty-one Engravings.

                      =GENERAL TABLE OF CONTENTS.=

    Brewster's Carriage Manufactory, New York. One engraving.
    The Parlor or Cabinet Organs of Mason & Hamlin.
    The New Wheeler & Wilson Sewing Machine.
    Howe's Improved Scales.
    The Chickering Pianos.
    The Ingersoll Rock Drill.
    Photo-engraving.
    The Paper Product of the United States.
    Electrical Indicator for Exhibiting the Rotation of the Earth. Two
  engravings.
    The Elevated Railroad Nuisance.
    Steam Boilers.
    Progress of our Western Industries.
    The Decline of the Whaling Industry.
    Transmitting Power by Electricity.
    Native Magnesium Salts.
    Scientific American Export Edition for June.
    The Eothen Arctic Expedition.
    Patent Matters in Congress.
    The Turkish Bath.
    Remarkable Locomotive Performances.
    The United States Building at the Paris Exposition.
    Recent Ship Designs.
    Figures which Seem Untruthful.
    The Hotchkiss Ship's Log.
    Starting New Industries.
    The Telephone at Sea.
    Horizontal Condensing Engine at the Exposition. One engraving.
    Deep Boring.
    Whitening Positives.
    Mr. Thomas A. Edison. One engraving.
    Patteson's Improved Car Coupling. One engraving.
    Project for Increasing the Water Power of Pennsylvania.
    A Japanese Built Ironclad.
    A Great Public Nuisance.--The Steam Street Railways
    New York City.
    What the South Owes New England.
    New Mechanical Inventions.
    Iridescent Glass.
    Fast Paper Making.
    Effect of Gas on Cotton Goods.
    Electrotypes of the Brain.
    Astronomical Notes for July. With Three figures, giving the
  Positions, Rising and Setting of the Planets.
    Sun Spots.
    Removing Spots from Cloths.
    "American" New Process Milling.
    New Agricultural Inventions.
    A Defense of Sludge Acid.
    Shad Hatching at Havre de Grace, Md.
    Improved Wrench. Two engravings.
    A Drygoods Palace Car.
    Radial Drilling Machine. One engraving.
    Improved Self-oiling Car Wheel. Three engravings.
    The Whitehead Torpedo. One engraving.
    A Californian Wheat Farm.
    Edison's Telephonic Researches. Eleven figures.
    New Inventions.
    New Electric Light.
    Quick Freight Time.
    The Adams Gas Process. Three engravings.
    The Invention of the Microphone.
    Preparation of Iron Fuels.
    Millstones.
    An Hour with Edison. Four engravings.
    Suspension Bridge Accident.
    Mill Explosion Science.
    Learn Something.
    Unsuitable Steam Vessels. One engraving.
    Our Naval Tubs.
    Leaves and their Functions.
    Lever and Cam Valve. Two engravings.
    An Ingenious Toy. One engraving.
    Milk as a Substitute for Blood Transfusion.
    Dr. Brown-Sequard.
    Odd Uses of Paraffin.
    American Institute Exhibition.
    Solidification of Petroleum.
    A Simple Fire-escape.
    Mr. Edison on the Microphone.
    Driving Piles in Sand.
    Is our Globe Hollow?
    The Best Penwiper.
    The Etiology of Asiatic Cholera.--A New Theory.
    Diagnosis.
    Proposed Process for the Fixation of Atmospheric Nitrogen. Two
  figures.
    Hallucinations.
    Perils of Base-ball Playing.
    Music Boxes.
    Electric Light Photography.
    Improved Beehive. Three engravings.
    A Good Act.
    Improved Gas Condenser. Two engravings.
    American Crop Prospects.
    The Launch of the Nipsic.
    The Swiss House at the French Exposition. One engraving.
    The Ingenuity of Bees.
    The St. Benoit Twins. One engraving.
    Improved Method of Milling.
    A Remarkable Meteoric Phenomenon.
    Drinking Water.
    Where to Observe the Solar Eclipse of July 29th.
    Explorations and Surveys.
    Tests for Good Burning Oil.
    Curious Hedge Figures. One engraving.
    Food Supply of Paris.
    The Leona Goat Sucker. One engraving.
    Oatmeal.
    Salt in Beer.
    Dr. Morfit's Method of Preserving Animal and Vegetable Food.
    The Ring of Fire, and the Volcanic Peaks of the West Coast of the
  United States.
    To Imitate Ground Glass.
    Railroad Birds.
    Improved Variable Automatic Cut-off. Four engravings.
    The Uses of Mechanism.
    Working Gold Ores.
    The Sun. With nine engravings. An excellent paper.
    Professor Edison's New Carbon Rheostat. Two engravings.
    The Chase Elemental Governor. Two engravings.
    Chinese Wine Powder.
    Amber Varnish.
    The Alkaloids of Opium.
    Microscopy.
    Is the Moon Inhabited?
    Description of the Recent Most Important Mechanical Inventions.
    Counterfeiting American Goods.
    The Steam Street Railways of New York City.
    Improved Piston Rod Stuffing Box. One engraving.
    Improved Automatic Fan. One engraving.
    Wandering Needles.
    Improved Step Box. One engraving.
    Heat Conductivity.
    New Volcano in Peru.
    Wood Carver of Simla. One engraving.
    Natural History Notes.
    Belgium, Holland, and England.
    Jointed Artillery.
    The Armstrong 100-ton Gun.
    The Phonograph.
    Scientific American Boat Drawings.
    Wire Tramway Worked by Water Wheels.
    Shell Polishing.
    Floating Batteries at Kertch.
    Apparatus for Administering Medicine to Horses. One engraving.
    Apprentice Shops for the Boys.
    A Boat Older than the Ark. Three figures.
    Employment of Ships against Forts.
    The Otto Bicycle. One engraving.
    A Simple Gas Generator. One engraving.
    Labor in Scotland.
    The Cattle Drives of 1878.
    Effects of Emancipation.
    A New Trouble with French Wines.
    The New Twin Steamer "Calais-Douvres." One engraving.
    Industrial Drawing and Art Studies.
    Vulcanizing Rubber.
    Strawberries and Constipation.
    Professor Langley's Papers on the Sun.
    Destruction vs. Construction of Ironclads.
    How Raisins are Prepared.
    The Sun.--A Total Eclipse. With six engravings.
    The Bishop of Manchester on British Trade Depression.
    A New Insect Pest.
    Death of a Giant.
    Edison's Phonomotor. Two engravings.
    Excavating Scoop. One engraving.
    Treatment of Acute Rheumatism.
    How a Horse Trots.
    Danger of Carbolic Acid Dressings.
    Welded Union and Rebel Bullets. One engraving.
    Indicator of a Steamboat Engine.
    A Remedy for the Effects of the Poison Ivy.
    Thymol.
    Copper Oysters.
    The Use of Antimony in Batteries.
    Photographs on Silk.
    How to Use a File. A valuable practical paper.
    Our Iron Industry.
    Two Ways of Looking at the Same Facts.
    New Screw-cutting Lathe. One engraving.
    New Cloth Measuring Apparatus. One engraving.
    Moth Remedies.
    Gampert's Wood-sole Shoe. Three engravings.
    Science and Sentiment.
    American Coal in Europe.
    An Active Volcano in the Moon.
    Tic-douloureux.
    Landing of Cleopatra's Needle. One large engraving.
    Heat Conductivity.
    The Total Eclipse of the Sun, July 29. Two figures.
    New Iron Fence. Two engravings.
    The Adjutant. One engraving.
    A New Disinfectant.
    The Curiosities of Tobacco.
    Preserving Fish by Hydraulic Pressure.

Answers to Correspondents, embodying a large quantity of valuable
information, practical recipes, and instructions in various arts.

Single numbers of the Scientific American Export Edition, 50 cents. To
be had at this office, and at all news stores.

                        MUNN & CO., PUBLISHERS,
                                37 PARK ROW, NEW YORK.

To Advertisers: =>Manufacturers and others who desire to secure foreign
trade may have large and handsomely displayed announcements published in
this edition at a very moderate cost.

The Scientific American Export Edition has a large guaranteed
circulation in all commercial places throughout the world. Address MUNN
& CO., 37 Park Row, New York.

       *       *       *       *       *




                           =Advertisements.=
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[Illustration: A KEY THAT WILL WIND ANY WATCH]
AND NOT WEAR OUT

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                J. S. BIRCH & CO., 33 Dey Street, N. Y.
  ----------------------------------------------------------------------
THE GEOLOGICAL ANTIQUITY OF Flowers and Insects. By J. E. TAYLOR, F.G.S.
A plain, comprehensive review of the subject, bringing forward many
instructive facts; with six illustrations. The invariable correlation
between insects and flowers. How they are fossilized. Fossil botany.
Geological Evidences of Evolution. Correspondence in the succession of
Animal and Vegetable life. Flowers necessary to Insects, and Insects
necessary to Flowers. Insects and Plants in the Devonian, the
Switzerland Lias, the English Stonesfield Slate, the Tertiary Strata,
the Coal Measures, a Greenland, and other formations. A Peculiar Aspect
of Evolution. Contained in SCIENTIFIC AMERICAN SUPPLEMENT NO. =120.=
Price 10 cents. To be had at this office and of all newsdealers.
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THE PHONOGRAPH AND ITS FUTURE. BY THOMAS A. EDISON. The instrument and
its Action. Durability, Duplication, and Postal Transmission of
Phonograph Plates. The probable great utility of the Phonograph in
Letter-writing, Business Correspondence and Dictation; Literature;
Education; Law; Music; Oratory, etc. Application to Musical Boxes, Toys,
and Clocks. Telegraphy of the Future; the Phonograph and Telephone
combined. Being a most interesting and valuable paper by the author and
inventor of the Phonograph himself. Contained in SCIENTIFIC AMERICAN
SUPPLEMENT, NO. =124.= Price 10 cents. To be had at this office and of
all newsdealers.
  ----------------------------------------------------------------------
                                  THE
[Illustration: "Scientific American." In Gothic script]

            =The Most Popular Scientific Paper in the World.
                          THIRTY-THIRD YEAR.=

             =Only $3.20 a Year including Postage. Weekly.
                          52 Numbers a Year.=

=This widely circulated= and splendidly illustrated paper is published
weekly. Every number contains sixteen pages of useful information, and a
large number of original engravings of new inventions and discoveries,
representing Engineering Works, Steam Machinery, New Inventions,
Novelties in Mechanics, Manufactures, Chemistry, Electricity,
Telegraphy, Photography, Architecture, Agriculture, Horticulture,
Natural History, etc.

=All Classes of Readers= find in THE SCIENTIFIC AMERICAN a popular
_resume_ of the best scientific information of the day; and it is the
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=Terms of Subscription.=--One copy of THE SCIENTIFIC AMERICAN will be
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       *       *       *       *       *




  ----------------------------------------------------------------------
                            WALTHAM WATCHES.

             _Improved in Quality, but no higher in price._

After this date, we shall sell none but =New Model Waltham Watches=,
particulars of which will be found in our New Price List.

Every one concedes that genuine WALTHAM watches are superior to all
others, and at present prices they are within the reach of all.

We continue to send single watches by mail or express to any part of the
country, no matter how remote, without any risk to the purchaser.

Price List sent free and postpaid.

  _Address_ HOWARD & CO.,
              =No. 264 Fifth Ave., New York.=

_All silver cases for the_ NEW MODEL WATCHES _are made of sterling
silver, and cases as well as movements are guaranteed by special
certificate._
  ----------------------------------------------------------------------
[Illustration:

                           BEST AND CHEAPEST
                               FOOT POWER
                             SCREW CUTTING
     $85.                    ENGINE LATHES


                        SEE FULL DESCRIPTION IN
                      SCIENTIFIC AMERICAN JULY 27
                     SEND FOR ILLUSTRATED CATALOGUE
                           GOODNOW & WIGHTMAN
                    176 WASHINGTON ST. BOSTON MASS.
]
  ----------------------------------------------------------------------
                    The Midsummer Holiday Scribner.

                         ANOTHER ROYAL NUMBER.

            Charming Writers--New Artists--Superb Engraving.

The August number of this progressive magazine is the third "Midsummer
Holiday" issue, and the publisher is confident that in literary and
artistic excellence it will be found fully equal to, if not in advance
of, its predecessors, which met with such distinguished favor from the
press and the public.

It opens with a Frontispiece,

                      =A NEW PORTRAIT OF BRYANT,=

Drawn in crayon, from life, by WYATT EATON, and engraved by COLE, with a
sketch of the haunts and homes of Bryant, by HORATIO N. POWERS, with
numerous wood-cuts.

Among the other illustrated material is

                     "=A SEA-PORT ON THE PACIFIC,="

By MARY HALLOCK FOOTE. The drawings are also by Mrs. Foote, and are
engraved by Marsh, Cole, and others. They have not been excelled in
magazine literature for charm, picturesqueness, and fine engraving. A
paper of wide interest is

                   "=TO SOUTH AFRICA for DIAMONDS!="

By Dr. W. J. MORTON, a narrative of personal experience in the mines,
with striking illustrations of this romantic and curious life. There are
also

                      =TWO CHARMING FIELD PAPERS=:

"Sharp Eyes" by JOHN BURROUGHS, with illustrations by a new artist;
"Glimpses of New England Farm Life," by R. E. ROBINSON, a paper of rare
picturesque interest.

There are illustrated poems by Dr. HOLLAND and J. T. TROWBRIDGE; also,
poems by STEDMAN, BRET HARTE, and others.

THE ILLUSTRATIONS are by Wyatt Eaton, Mary Hallock Foote, Vanderhoof,
Waud, Frederick Dielman, R. Swain Gifford, Jervis McEntee, Henry Farrer,
Winslow Homer, J. E. Kelly, Walter Shirlaw, L. C. Tiffany, Thomas Moran,
Will H. Low, Mrs. Fanny Eliot Gifford, and others.

The shorter stories are by STOCKTON and HENRY JAMES, Jr.

DR. EGGLESTON'S STORY of WESTERN LIFE reaches its climax, and will end
in October.

A New Novel,

                      "=FALCONBERG," by BOYESEN,=

Begins in this issue. It is a story of immigrant life in America, told
by one of the most promising of the younger generation of novelists, and
will be read with interest abroad as well as at home.

The Editorial Departments include "Our Commune," "The Death of Bryant,"
"Greatness in Art," "A Rural Art Association," "Recent Improvements in
Telephony," thoughtful and suggestive Book Reviews, Humorous Sketches
and Verses by new hands, &c., &c.

The frontispiece is upon a peculiar tint of paper, manufactured by
Warren expressly for Eaton's portrait of Bryant. The printing is by De
Vinne, from the press of Francis Hart & Co., who take rank among the
foremost printers of the world.

EDITION =85,000.= Price 35 cents Sold by all News-dealers and
Book-sellers.

                      =SCRIBNER & CO., NEW YORK.=
  ----------------------------------------------------------------------
                     Baker Rotary Pressure Blower.

  [Illustration]

                            (FORCED BLAST.)

                    Warranted superior to any other.

                            WILBRAHAM BROS.
                          2318 Frankford Ave.
                                   PHILADELPHIA.
  ----------------------------------------------------------------------
                      OUTWARD MARKS OF A GOOD COW.

  By Capt. JOHN C. MORRIS, Pa. Carelessness in Breeding. How to Select
  for Breeding. Marks of the Handsome Cow. Care and Training of the
  Heifer. Infallible Marks of Good Milkers. Distinguishing Marks and
  Characteristics of the "Bastard" and the "Bogus" Cow, etc. Contained,
  with useful Remarks on Bee Culture, in SCIENTIFIC AMERICAN SUPPLEMENT
  NO. =135.= Price 10 cents. To be had at this office and of all
  newsdealers.
  ----------------------------------------------------------------------
                          PATENTS AT AUCTION.

  Regular Monthly Sales the first week of each month by George W.
  Keeler, Auctioneer, at his salesrooms, 53 and 55 Liberty Street, N.
  Y. For terms, etc., address The New York Patent Exchange, 53 Liberty
  St., N. Y.
  ----------------------------------------------------------------------
                  SPARE THE CROTON AND SAVE THE COST.

                          Driven or Tube Wells
  furnished to large consumers of Croton and
  Ridgewood Water. WM. D. ANDREWS & BRO., 414 Water St., N. Y., who
  control the patent for Green's American Driven Well
  ----------------------------------------------------------------------
  [Illustration]

                                 BIBB'S
                     Celebrated Original Baltimore
                           Fire Place Heaters
                         Mantels and Registers.
                           B. C. BIBB & SON,
                             Baltimore, Md.

  Best workmanship. Lowest prices guaranteed. Send for circulars.
  ----------------------------------------------------------------------
                       JAPANESE ART MANUFACTURES.

  By Christopher Dresser, Ph.D., etc. Paper read before Society of
  Arts. The Japanese Potter at Work. Curious mode of Making Scarfs. How
  the Japanese Print on Cloth. Japanese Process for Silk Ornamentation.
  Japanese Weaving. How Fine Japanese Fans are made. Japanese Method
  of Making Moulds for Ornamental Castings for Vessels, Bronzes,
  etc. Japanese Lacquer Manufacture. Curious Method of Decorating
  Lacquer Work. The Love and Pursuit of the Beautiful in Japan. A very
  entertaining, instructive, and comprehensive paper. Contained in
  SCIENTIFIC AMERICAN SUPPLEMENT NO. =115.= Price 10 cents. To be had
  at this office and of all newsdealers.
  ----------------------------------------------------------------------
  [Illustration]

                               BURNHAM'S

                            STANDARD TURBINE

                              WATER WHEEL.

                      WARRANTED BEST AND CHEAPEST.

                        N. F. BURNHAM, YORK, PA.
  ----------------------------------------------------------------------
                                RUPTURE

  Relieved and cured, without the injury trusses inflict, by Dr. J. A.
  Sherman's method of support and curative externally applied. Office,
  251 Broadway, N. Y. His book, with photographic likenesses of bad
  cases before and after cure, mailed for 10 cents. Beware of imitators.
  ----------------------------------------------------------------------
  =25= =NEW YEAR CARDS=, with name, 20c. 25 Extra Mixed, 10c. Geo. I.
      Reed & Co., Nassau, N. Y.
  ----------------------------------------------------------------------
                          =ARTIFICIAL LIGHT.=

  We have just introduced this important facility, which enables us to
  prosecute our work in =cloudy weather=, and to push through hurried
  orders =in the night=.

  [Illustration:
                         NEW METHOD OF ENGRAVING
                              Moss' Process.
                           Photo Engraving Co.
                         67 Park Place, New York.
  L. SMITH HOBART, President.              JOHN C. MOSS, Superintendent.
  ]

                             RELIEF PLATES

  For Newspaper, Book, and Catalogue Illustrations. Engraved in
  Type-Metal, by a new Photo-Chemical Method, from all kinds of Prints,
  Pen Drawings, Original Designs, Photographs, etc., =much cheaper
  than wood cuts=. These plates have a perfectly smooth printing
  surface, and the lines are =as deep, as even, and as sharp= as they
  could possibly be cut by hand. We guarantee that they will print
  satisfactorily, on wet or dry paper, and on any press where type or
  wood cuts can be so printed. Electrotypes may be made from them in
  the usual way.

  =Our plates are now used by the principal publishers and manufacturers
  in every State in the Union.=   _Send stamp for illustrated Circular._
  ----------------------------------------------------------------------
               =State, County and Shop Rights For Sale.=

  The Patent Adjustable Die Co. invite the attention of Printers,
  Lithographers, Paper Box Makers, Leather, Cloth, and Metal Workers,
  and all who use dies of any description, or who cut by laborious
  hand work patterns of any size or shape, to their patent device for
  cutting any desired outline at a cost of a few cents, and doing
  it with exactness, cutting from one to three hundred at a single
  pressure. Among those who have purchased shop rights, the following
  are referred to: Rand, Macnally & Co.; Donnelly, Loyd & Co.; Shoeber
  & Carqueville Lithograph Co.; Wright & Leonard; Frank Roehr; Gregory
  & Staiger; Western Label Man. Co.; S. A. Grant & Co., Cincinnati.

                       PATENT ADJUSTABLE DIE CO.,
                                No. 96 Dearborn Street, Chicago, Il.
  ----------------------------------------------------------------------
  [Illustration]

                    =BARNES' FOOT POWER MACHINERY.=

  13 Different machines with which Builders, Cabinet Makers, Wagon
  Makers, and Jobbers in miscellaneous work can compete as to QUALITY
  AND PRICE with steam power manufacturing; also Amateurs' supplies.
  MACHINES SENT ON TRIAL.

  Say where you read this, and send for catalogue and prices.

                          W. F. & JOHN BARNES,
                     Rockford, Winnebago Co., Ill.

                           Eastern Agency for

                    =Barnes' Foot Power Machinery.=

  _Full line in stock_ at factory prices. Can be seen in operation at
  CHAS. E. LITTLE'S, 59 Fulton St., N. Y. _Cast Steel Pump Log Augers
  and Reamers a specialty._
  ----------------------------------------------------------------------
  =$250.= HEALD, SISCO & CO.'S "=RELIABLE=" 20 Horse Power, Stationary,
  Horizontal, Double-crank Steam Engine. Complete with Judson Governor,
  Boiler-feed Pump, Water Heater, etc. Best and cheapest in the world,
  and fully guaranteed. TWO HUNDRED AND FIFTY DOLLARS. Send for
  circular to
                HEALD, SISCO & CO., Baldwinsville, N. Y.
  ----------------------------------------------------------------------
                       =Wood-Working Machinery,=

  Such as Woodworth Planing, Tonguing, and Grooving Machines, Daniel's
  Planers, Richardson's Patent Improved Tenon Machines, Mortising,
  Moulding, and Re-Saw Machines, and Wood-Working Machinery generally.
  Manufactured by

                      WITHERBY, RUGG & RICHARDSON,
                                   26 Salisbury Street, Worcester, Mass.

  (Shop formerly occupied by R. BALL & CO.)
  ----------------------------------------------------------------------
                         =PATENT MINERAL WOOL.=

  Entirely _Fireproof_, undecaying, and the best _non-conductor of heat,
  cold, or sound_. Cheaper than hair-felt.

                              =A. D. ELBERS=,
  _P. O. Box 4461._                                  26½ Broadway, N. Y.
  ----------------------------------------------------------------------
  [Illustration: WROUGHT IRON BEAMS & GIRDERS]

  THE UNION IRON MILLS, Pittsburgh, Pa., Manufacturers of improved
  wrought iron Beams and Girders (patented).

  The great fall which has taken place in the prices of Iron,
  and especially in Beams used in the construction of FIRE PROOF
  BUILDINGS, induces us to call the special attention of Engineers,
  Architects, and Builders to the undoubted advantages of now erecting
  Fire Proof structures; and by reference to pages 52 & 54 of our
  Book of Sections--which will be sent on application to those
  contemplating the erection of fire proof buildings--THE COST CAN
  BE ACCURATELY CALCULATED, the cost of Insurance avoided, and the
  serious losses and interruption to business caused by fire; these
  and like considerations fully justify any additional first cost. It
  is believed, that, were owners fully aware of the small difference
  which now exists between the use of Wood and Iron, in many cases the
  latter would be adopted. We shall be pleased to furnish estimates
  for all the Beams complete, for any specific structure, so that the
  difference in cost may at once be ascertained. Address

                                CARNEGIE, BROS. & CO., Pittsburgh, Pa.
  ----------------------------------------------------------------------
                            =Pond's Tools=,

                 =Engine Lathes, Planers, Drills, &c.=

  Send for Catalogue. DAVID W. POND, Successor to LUCIUS W. POND.
  =Worcester, Mass.=
  ----------------------------------------------------------------------
  =$3 GOLD PLATED WATCHES.= Cheapest in the known world. _Sample Watch
    Free to Agents._ Address, A. COULTER & Co., Chicago.
  ----------------------------------------------------------------------
                          =EAGLE FOOT LATHES,=

  [Illustration]

  Improvement in style. Reduction in prices April 20th. Small Engine
  Lathes, Slide Rests, Tools, etc. Also Scroll and Circular Saw
  Attachments, Hand Planers, etc. Send for Catalogue of outfits for
  Amateurs or Artisans.

                          WM. L. CHASE & CO.,
                     95 & 97 Liberty St., New York.
  ----------------------------------------------------------------------
                  =The George Place Machinery Agency=
                   =Machinery of Every Description.=
             121 Chambers and 103 Reade Streets, New York.
  ----------------------------------------------------------------------
                    CIVIL and MECHANICAL ENGINEERING

  At the Rensselaer Polytechnic Institute, Troy, N. Y. Next term
  begins Sept. 12. The Annual Register for 1878 contains a list of the
  graduates for the past 52 years, with their positions; also, course
  of study, requirements for admission, expenses, etc. Address Wm. H.
  Young, Treas'r.
  ----------------------------------------------------------------------
                           =THE DRIVEN WELL.=

  Town and County privileges for making =Driven Wells= and selling
  Licenses under the established =American Driven Well Patent=, leased
  by the year to responsible parties, by

                        =WM. D. ANDREWS & BRO.,=
                                                             NEW YORK.
  ----------------------------------------------------------------------
                              _NOW READY._

                      =The Army of the Republic:=

                       ITS SERVICES AND DESTINY.
                        =BY HENRY WARD BEECHER.=

  An Oration at the Re-union of the Army of the Potomac, at Springfield,
  Mass., June 5th, comprising Christian Union Extra No. 12.

                            Price 10 Cents.
                         =THE CHRISTIAN UNION,=
                          27 Park Place, N. Y.
  ----------------------------------------------------------------------
  [Illustration: WOOD WORKING MACHINERY. PLANING, MATCHING, MOLDING,
  MORTISING, TENONING, CARVING, MACHINES. BAND & SCROLL SAWS UNIVERSAL
  AND VARIETY WOOD WORKERS, &c. &c. =J. A. FAY & CO.= CINCINNATI,
  O.U.S.A.]
  ----------------------------------------------------------------------
                       =Lathes, Planers, Shapers=

  Drills, Bolt and Gear Cutters, Milling Machines. Special Machinery. E.
  GOULD & EBERHARDT, Newark, N. J.
  ----------------------------------------------------------------------
                            =A BLOCK PLANE,=
               =WITH ADJUSTMENT FOR SETTING THE CUTTER.=

  [Illustration]

                  =Length, 7½ inches; 1¾ inch Cutter.=

                             =PRICE $1.00.=

  Sent by mail, to any address, postage prepaid, on receipt of price.

  Price of the above Plane _without_ the adjustment, 70c. Write for an
  Illustrated Descriptive Circular and Price List of our full line of
  "Defiance" Metallic Planes to

                      BAILEY WRINGING MACHINE CO.,
                                           99 Chambers Street, New York.
  ----------------------------------------------------------------------
  [Illustration]
                         READ THIS! READ THIS!!

                       Adjustable Safety Stilts.

                        A NOVELTY FOR THE BOYS.

                     A Great Chance to Make Money.

  Parties wishing to invest in a paying business can do so with a small
  capital by addressing

                                      CHAS. S. SHUTE, Springfield, Mass.

                  Send Stamp for Illustrated Circular.
  ----------------------------------------------------------------------
                               =VINEGAR.=

  I teach by letter the new English Quick-Vinegar-Process, that is, how
  vinegar is made in one day without drugs. For particulars and terms,
  address

                                   J. H. LAUTERBACH, Zanesville, Ohio.
  ----------------------------------------------------------------------
                      =Foundry and Machine Shop,=
  in live Western town, for sale cheap. Address Box 275, Winona, Minn.
  ----------------------------------------------------------------------
                             WOOD ENGRAVING

  At Photo-Engraving Process Rates, by
                                     T. P. DONALDSON, 33 Park Row, N. Y.
  ----------------------------------------------------------------------
                     =SHEET METAL WORKS FOR SALE.=

  The largest and best equipped establishment in the United States
  for the manufacture of Sheet Metal Architectural and Cornice Works,
  and Ornamental Stamped and Spun Zinc Work. Located at an important
  station on the Pittsburgh, Fort Wayne and Chicago Railroad. Taxes and
  rents low. The ornamental sheet metal work upon the Main Building for
  the Centennial Exposition was made at these shops. The real estate,
  tools, and equipments cost some sixty thousand dollars. Will be sold
  at a very great sacrifice. Call on or address LUCIEN L. GILBERT,
  Salem, Columbiana Co., Ohio.
  ----------------------------------------------------------------------
  THE BEST FRICTION CLUTCH IN THE _World_ for hoisting coal, logs, or
  freight. It can be fitted direct on line shaft, run at high speed, and
  start without shock. _No end thrust_ on journals. Patent Safety
  Elevators at low prices.

                                    D. FRISBIE & CO., New Haven, Conn.
  ----------------------------------------------------------------------
  [Illustration:
                          !!New and Improved!!

                         Engraving Process!!!!

                   Perfect Substitute for Wood-Cuts.

                          Photo-Plate Company

                         63 Duane St. New York.

  Can be printed on an ordinary Press.

  RELIEF PLATES in hard Type Metal FOR Newspaper & Book Illustration.

  Send Stamp for Illustrated Circular.

                        MUCH CHEAPER THAN WOODCUTS.

  ARTISTIC PRINTING.

  FINE ELECTROTYPING.

                         State where you saw this.
  ]
  ----------------------------------------------------------------------
  [Illustration]

                            =$4. TELEPHONES=

  For Business Purposes, ours excel all others in clearness and volume
  of tone. Illus. circular and testimonials for 3 cts.

                              Address J. R. HOLCOMB, Mallet Creek, Ohio.
  ----------------------------------------------------------------------
  EXPLOSIVE DUST. A COMPREHENSIVE description of the Dangers from Dust
  in various Manufactures and the Cause of many Fires. How combustible
  substances can explode. Spontaneous Combustion of Iron, Charcoal, and
  Lampblack in Air. Flour Dust and Brewery Dust Explosions. Explosions
  of Coal Dust in Mines. Contained in SCIENTIFIC AMERICAN SUPPLEMENT
  NO. =125.= Price 10 cents. To be had at this office and of all
  newsdealers.
  ----------------------------------------------------------------------
                        =Can I Obtain a Patent?=

  This is the first inquiry that naturally occurs to every author or
  discoverer of a new idea or improvement. The quickest and best way
  to obtain a satisfactory answer, without expense, is to write to us
  (Munn & Co.), describing the invention, with a small sketch. All we
  need is to get the _idea_. Do not use pale ink. Be brief. Send stamps
  for postage. We will immediately answer and inform you whether or
  not your improvement is probably patentable; and if so, give you the
  necessary instructions for further procedure. Our long experience
  enables us to decide quickly. For this advice we make _no charge_.
  All persons who desire to consult us in regard to obtaining patents
  are cordially invited to do so. We shall be happy to see them in
  person at our office, or to advise them by letter. In all cases, they
  may expect from us a careful consideration of their plans, an honest
  opinion, and a prompt reply.

  _What Security Have I_ that my communication to Munn & Co. will be
  faithfully guarded and remain confidential?

  _Answer._-You have none except our well-known integrity in this
  respect, based upon a most extensive practice of thirty years'
  standing. Our clients are numbered by hundreds of thousands. They
  are to be found in every town and city in the Union. Please to
  make inquiry about us. Such a thing as the betrayal of a client's
  interests, when committed to our professional care, never has
  occurred, and is not likely to occur. All business and communications
  intrusted to us are kept _secret and confidential_.

                         Address =MUNN & CO.,=
                 Publishers of the SCIENTIFIC AMERICAN,
                                              =37 Park Row New York.=
  ----------------------------------------------------------------------




  =Advertisements.=
  ----------------------------------------------------------------------
  =Inside Page, each insertion - - - 75 cents a line.
  Back Page, each insertion - - - $1.00 a line.=
                       (About eight words to a line.)

  _Engravings may head advertisements at the same rate per line, by
  measurement, as the letter press. Advertisements must be received at
  publication office as early as Thursday morning to appear in next
  issue._
  ----------------------------------------------------------------------
                             =TELEPHONES,=

  Perfect working, at reduced prices. Send for illustrated circular to
  =TELEPHONE SUPPLY CO.,=
                                               =Box 3224, Boston, Mass.=
  ----------------------------------------------------------------------
  [Illustration:
                               =H.W. JOHNS'=
                                 ASBESTOS
                                 TRADEMARK
  ]

              =LIQUID PAINTS, ROOFING, BOILER COVERINGS,=
        Steam Packing, Sheathings, Fire Proof Coatings, Cements.
         SEND FOR SAMPLES, ILLUSTRATED PAMPHLET AND PRICE LIST.
             =H. W. JOHNS M'F'G Co., 87= MAIDEN LANE, N. Y.
  ----------------------------------------------------------------------
  =Mill Stones and Corn Mills.=

  We make Burr Millstones, Portable Mills, Smut Machines, Packers, Mill
  Picks, Water Wheels, Pulleys, and Gearing, specially adapted to Flour
  Mills. Send for catalogue.

                                    =J. T. NOYE & SON, Buffalo, N. Y.=
  ----------------------------------------------------------------------
  [Illustration]
                          =WARRANTED THE BEST.
                     1 H. P. Boiler & Engine, $150.
                     2 H. P., $175. 3 H. P., $200.=

  Tested to 200 lbs. Steam.

                           =LOVEGROVE & CO.,
                   152 N. 3d St., Philadelphia, Pa.,=

  Builders of Engines and Boilers, 1 to 100 horse power. Send for
  circulars and prices, and state size and style you want.
  ----------------------------------------------------------------------
                           ESTABLISHED 1844.

                           =JOSEPH C. TODD,=

  ENGINEER and MACHINIST. Flax, Hemp, Jute, Rope, Oakum and Bagging
  Machinery, Steam Engines, Boilers, etc. I also manufacture Baxter's
  New Portable Engine of 1877. Can be seen in operation at my store. A
  one horse-power, portable engine, complete, $125; two horse-power,
  $225; two and a half horse-power, $250; three horse-power, $275.
  Manufactured exclusively by

                             =J. C. TODD,=
              10 Barclay St., New York, or Paterson, N. J.
  ----------------------------------------------------------------------
                               =CAMERON=
                             =Steam Pumps=

    For Mines, Blast Furnaces, Rolling Mills, Oil Refineries, Boiler
                              Feeders, &c.

  For Illustrated Catalogue and _Reduced_ Price List send to =Works, Foot
  East 23d St., New York.=
  ----------------------------------------------------------------------
  [Illustration: WIRE ROPE]

  Address JOHN A. ROEBLING'S SONS, Manufacturers, Trenton, N. J., or 117
  Liberty Street, New York.

  Wheels and Rope for conveying power long distances. Send for circular.
  ----------------------------------------------------------------------
  =$1200 Salary.= Salesmen wanted to sell our Staple Goods to dealers.
  No peddling. =Expenses= paid. Permanent employment. address S. A.
  GRANT & CO., 2, 4, 6 & 8 Home St., Cincinnati, O.
  ----------------------------------------------------------------------
                            _Working Models_

  And Experimental Machinery, Metal or Wood, made to order by
                                      J. F. WERNER, 62 Centre St., N. Y.
  ----------------------------------------------------------------------
                   B. W. Payne & Sons, Corning, N. Y.
                          Established in 1840.

  [Illustration]

                          Eureka Safety Power.

              |h.p.   cyl.     ht.   space.   wt.  price.
              -------------------------------------------
              | 2  |3-1/8x4| 48 in.| 40x25 |  900 | $150 |
              -------------------------------------------|
              | 4  | 4x6   |  56   | 46x30 | 1600 |  250 |
              -------------------------------------------|
              | 6  | 5x7   |  72   | 72x42 | 2700 |  400 |
              -------------------------------------------
              |_Also_, =SPARK ARRESTING PORTABLES=, _and_|
              | =Stationary Engines= _for Plantations_.  |
              | Send for Circulars.                      |
  ----------------------------------------------------------------------
  Patent Wood-working Machinery, Band Saws Scroll Saws, Friezers, etc.
  Cordesman, Egan & Co., Cincin'ti, O.
  ----------------------------------------------------------------------
                           =CORLISS ENGINES.=

  Beam, horizontal, vertical, condensing, and non-condensing Steam
  Engines.

                   =Machine Tools, Sugar Machinery.=

             =Facilities for Constructing Heavy Machinery.=

  Send for Circular.

                         PASSAIC MACHINE WORKS,
                  WATTS, CAMPBELL & CO., Proprietors,
                                                           Newark, N. J.
  ----------------------------------------------------------------------
  [Illustration]

  THE ONLY Genuine GEISER SELF-REGULATING GRAIN SEPARATOR. Celebrated
  for its light and smooth movements, also SEPARATING and CLEANING all
  kinds of grain.

  Manufactured only by
                       THE GEISER M'F'G CO., Waynesboro, Franklin Co., Pa.
  ----------------------------------------------------------------------
                          =CIGAR BOX LUMBER,=

                        Manufactured by our new

                         =Patented Processes.=

  Poplar                                 1¼c.
  Mahogany                               2½c.
  Spanish Cedar Veneers                   ½c.
  Spanish Cedar, 2d quality              2¾c.
       "         1st and 2d quality      3¼c.
       "         1st           "         3¾c.
  No charge for cartage. Terms cash.

                         =GEO. W. READ & CO.,=
                                    =186 to 200 Lewis Street, New York.=
  ----------------------------------------------------------------------
                             =BELT PULLEY,=

  Lightest, strongest, and best made. Secured to the Shaft without Keys,
  Set Screws, Bolts or Pins; also, _Adjustable Dead Pulleys_ and
  _Taper-Sleeve Couplings_. Send for catalogue. Address Taper-Sleeve
  Pulley Works, Erie, Pa.
  ----------------------------------------------------------------------
  [Illustration:
                                MARVIN'S
                             FIRE & BURGLAR
                                 SAFES
                    COUNTER PLATFORM · WAGON & TRACK
                                 SCALES
                        MARVIN SAFE & SCALE CO.
                         ·265 BROADWAY. N. Y.·
  ----------------------------------------------------------------------
                            An assortment of
                       =WOOD-WORKING MACHINERY=
  made by Richards, London & Kelley (dissolved); also, a number of
  first-class =MACHINE TOOLS= (nearly as good as new) of Philadelphia
  construction, on hand and for sale. For list or inspection of machines
  and estimates, apply at the works of JOHN RICHARDS & CO., 22d and Wood
  Sts., Philadelphia, manufacturers of Standard Gauges and other
  Implements.
  ----------------------------------------------------------------------
  ON THE CARE OF HORSES. BY PROF. PRITCHARD, R. V. S. Showing the Proper
  Construction of Stables. Best Floor. Lighting and Ventilation.
  Hay-racks. Watering and Feeding. Grooming and Exercise. Cracked Heels;
  Lice; Colic; Mud Fever; Wind Galls. Also, in same number, facts about
  improved Cow Stables. How to keep Cows clean and maintain Pure Air in
  Stables. Increased Cleanliness and Convenience with Less Labor.
  Contained in SCIENTIFIC AMERICAN SUPPLEMENT NO. =123.= Price 10 cents.
  To be had at this office and of all newsdealers.
  ----------------------------------------------------------------------
  Every Man His Own Printer!

  [Illustration: The Excelsior]

  =$3 Press= Prints labels, cards etc. (Self-inker $5) =9= Larger sizes
  For business, pleasure, young or old Catalogue of Presses, Type,
  Etc., for 2 stamps.

                             =KELSEY & Co.=
                                                         =Meriden, Conn=
  ----------------------------------------------------------------------
  =Pyrometers=, For showing heat of Ovens, Hot Blast Pipes Boiler Flues,
  Superheated Steam, Oil Stills, &c.

                  HENRY W. BULKLEY, Sole Manufacturer,
                                                   149 Broadway, N. Y.
  ----------------------------------------------------------------------
                        =ICE AT $1.00 PER TON.=
                     The PICTET ARTIFICIAL ICE CO.,
                                LIMITED,
         Room 51, Coal and Iron Exchange, P. O. Box 3083, N. Y.
  ----------------------------------------------------------------------
                        LAP WELDED CHARCOAL IRON

  Boiler Tubes, Steam Pipe, Light and Heavy Forgings, Engines, Boilers,
  Cotton Presses, Rolling Mill and Blast Furnace Work.

                         =READING IRON WORKS,=
                                        =261 South Fourth St., Phila.=
  ----------------------------------------------------------------------
  =OPERA GLASSES= =At Reduced Prices.= Microscopes, Spectacles,
  Telescopes, Thermometers. Send for Illustrated Catalogue.

                             R. & J. BECK,
                                       921 Chestnut St., Philadelphia.
  ----------------------------------------------------------------------
  [Illustration]

                        WOOD-WORKING MACHINERY,
  New and improved, for special work. Boring Machines, Turning Lathes,
  Saw Arbors, Saw Benches, Scroll Saws, Panel Raisers, and other
  Wood Tools. We build the only patented Panel Raiser, with vertical
  spindles, all others being infringements on our patents of July 11
  and October 31, 1871.

                            =WALKER BROS.,=
                    =_73 and 75 Laurel St., Phila._=
  ----------------------------------------------------------------------
  ALCOHOLISM. AN INTERESTING Paper upon the Relations of Intemperance
  and Life Insurance. The average Risks and Expectancy of Life of
  the Temperate and of the Intemperate. Physiological action of
  Alcohol; stimulating the Nervous System, Retarding the Circulation.
  Alcohol Oxidized in the System. Insomnia, Congestion of the Lungs,
  Deterioration of Structure, Calculus, and Liver Diseases as results
  of Liquor. Extended Medical Testimony. Contained in SCIENTIFIC
  AMERICAN SUPPLEMENT NO. =125.= Price 10 cents. To be had at this
  office and of all newsdealers.
  ----------------------------------------------------------------------
                             =Telephones.=

  How made, adjusted, and operated by any person. Send stamp for full
  and interesting description, with illustrations and instructions. One
  pair first-class Telephones complete, except diaphragms, sent to any
  address upon receipt of $5.                 J.H. BUNNELL, Electrician,
                                              112 Liberty St., New York.
  ----------------------------------------------------------------------
  IMPORTANT FOR ALL CORPORATIONS AND MANF'G CONCERNS.--=Buerk's
  Watchman's Time Detector=, capable of accurately controlling the
  motion of a watchman or patrolman at the different stations of his
  beat. Send for circular.

               =J. E. BUERK, P. O. Box 979, Boston, Mass=

  N. B.--The suit against Imhaeuser & Co., of New York, was decided in
  my favor, June 10, 1874. A fine was assessed against them Nov. 11,
  1876, for selling contrary to the order of the court. Persons buying
  or using clocks infringing on my patent will be dealt with according
  to law.
  ----------------------------------------------------------------------
  THE HUGHES TELEPHONE. SIX FIGURES. Sound converted into Undulatory
  Electrical Currents by Unhomogeneous Conducting Substances in
  Circuit. The Simplest Telephone and the most sensitive Acoustical
  Instrument yet constructed. Instrument for Testing the Effect of
  Pressure on Various Substances. Astonishing Experiments which may
  be performed by any person with a few nails, pieces of sealing wax,
  a glass tube containing powders, and a few sticks of charcoal.
  Contained in SCIENTIFIC AMERICAN SUPPLEMENT NO. =128.= Price 10
  cents. To be had at this office and of all newsdealers.
  ----------------------------------------------------------------------
  [Illustration:
                      MEDAL & PREMIUM AWARDED TO
                               ALCOTT'S
                         TURBINE WATER WHEELS]

                    MANUFACT'D AT MOUNT HOLLY N. J.
  ----------------------------------------------------------------------
  "OLD RELIABLE." TO KNOW ALL about the =Best Pump= for Paper Makers,
  Tanners, Contractors, and for irrigation, send for illustrated
  pamphlet, 78 pages. HEALD, SISCO & CO., Baldwinsville, N. Y.
  ----------------------------------------------------------------------
  =BOOKS=, Papers. Want Agents. Send stamp. L. L. FAIRCHILD, Rolling
  Prairie, Wis.
  ----------------------------------------------------------------------
  =IT PAYS= to sell our Rubber Stamps and Novelties. Terms free. G. A.
  HARPER & BRO., Cleveland, O.
  ----------------------------------------------------------------------
                       DYSPEPSIA. BY DR. C. F. KUNZE.
  Symptoms. Appetite Diminished. Stomach
  Digestion much slower than Normal. Constipation. Symptoms in Children.
  Chronic Cases. Dyspepsia as caused by too much Food; by Indigestible
  Food; by General Derangement; by Altered Conditions of Innervation.
  Treatment. Nourishment should be Easily Digestible; taken Little at a
  Time; and Digested before more is taken. Necessity of Few and Plain
  Dishes. Treatment when Stomach is Overloaded. Aiding Gastric Juice.
  Treatment in Febrile Diseases. Contained in SCIENTIFIC AMERICAN
  SUPPLEMENT NO. =129.= Price 10 cents, To be had at this office and of
  all newsdealers.
  ----------------------------------------------------------------------
  [Illustration]

                         =SHEPARD'S CELEBRATED=

                     $50 Screw Cutting Foot Lathe.

  Foot and Power Lathes, Drill Presses, Scroll, Circular and Band Saws,
  Saw Attachments, Chucks, Mandrills, Twist Drills, Dogs, Calipers, etc.
  Send for catalogue of outfits for amateurs or artisans.

                         =H. L. SHEPARD & CO.,
                          88, 90 & 92 Elm St.,
                                                    Cincinnati, Ohio.=
  ----------------------------------------------------------------------
  =TO ADVERTISERS!= We will send free to all applicants who do any
  newspaper advertising, the THIRD EDITION of
                           =AYER & SON'S MANUAL=
  =FOR ADVERTISERS.= 160 8vo. pp. More complete than any which have
  preceded it. Gives the names, circulation, and advertising rates of
  several thousand newspapers in the United States and Canada, and
  contains more information of value to an advertiser than can be found
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  spending any money in newspaper advertising. Address =N. W. AYER &
  SON,= ADVERTISING AGENTS, Times Building, Philadelphia.
  ----------------------------------------------------------------------
                           =PORTLAND CEMENT,=

  ROMAN & KEENE'S. For Walks, Cisterns, Foundations, Stables, Cellars,
  Bridges, Reservoirs, Breweries, etc.

  Remit 10 cents for Practical Treatise on Cements.

                            S. L. MERCHANT & CO., 53 Broadway, New York.
  ----------------------------------------------------------------------
  [Illustration]

                     =NORTH'S UNIVERSAL LATHE DOG.
                              S. G. NORTH
                347 North 4th Street, Philadelphia, Pa.=
  ----------------------------------------------------------------------
                          =MACHINISTS' TOOLS.=
                       NEW AND IMPROVED PATTERNS.

  Send for new illustrated catalogue.

                      Lathes, Planers, Drills, &c.
                     =NEW HAVEN MANUFACTURING CO.,
                                                       New Haven, Conn.=
  ----------------------------------------------------------------------
  POINTS OF A GOOD HORSE. BEING the Report of the Committee appointed
  by the New England Agricultural Society to decide upon Rules for
  Guidance of Judges of Horses. The Points of Excellence. Size, Color,
  Symmetry of Body, Head and Neck, Eye and Ear, Feet and Limbs, fully
  described. Speed at the Trot, and in Walking, Style and Action, etc.,
  with the percentage allowed for each quality. The Standard Size and
  Speed for Matched Carriage Horses, Gents' Driving Horses, Family
  Horses, Park or Phæton Horses, etc. An excellent Guide in selecting
  animals. Contained in SCIENTIFIC AMERICAN SUPPLEMENT NO. =103=, price
  10 cents. To be had at this office and of all newsdealers.
  ----------------------------------------------------------------------
  [Illustration]

                          ="THE EAGLE CLAW."=
                The best Trap in the World for catching
                     FISH, ANIMALS & GAME.
  [Illustration]
                          One bait will catch
                             =Twenty Fish=.

  No. 1, for ordinary fishing, small game, &c. 35c.
  No. 2, for large fish, mink, musk-rats, &c. 75c.
  Sent by mail.               =J. BRIDE & CO.,=
                                          Mfrs., 297 Broadway, New-York.

  Send for Catalogue of useful novelties and mention this paper.
  ----------------------------------------------------------------------
                       EMERY  AND  CORUNDUM  WHEELS,
  for Grinding and Surfacing Metals and other materials. By ARTHUR H.
  BATEMAN, F. C. S. A paper read before the Society of Arts, London.
  Files, Chisels, Grindstones, Composition of Emery, where found,
  Quality, Specific Gravity, and Hardness, Manufacture of the wheels,
  Emery Powder, Buffing, Polishing, Cutting Power, Corundum. The
  Magnesian or Union Wheel, the Tanite, the Northampton, the Vulcanite,
  the Climax, the Vitrified, a porous wheel with central water supply.
  Fifty uses enumerated to which the wheels are put, for Metals,
  Stone, Teeth, Millboard, Wood, Agate, and Brick. How to mount a
  wheel. How to hold the work, and directions for various classes of
  work. Discussion and questions proposed and answered. Contained in
  SCIENTIFIC AMERICAN SUPPLEMENT, NO. =125=. Price 10 cents. To be had
  at this office and of all newsdealers.
  ----------------------------------------------------------------------
                             =THE BIGELOW=
                            =Steam Engine.=

                     BOTH PORTABLE AND STATIONARY.

  =The CHEAPEST AND BEST in the market. Send for descriptive circular
  and price list.=

                         =H. B. BIGELOW & CO.,
                                                     New Haven, Conn.=
  ----------------------------------------------------------------------
  [Illustration: Diamonds and Carbon]

  Shaped or Crude, furnished and set for Boring Rocks, Dressing Mill
  Burrs, Emery Wheels, Grindstones, Hardened Steel, Calender Rollers,
  and for Sawing Turning, or Working Stone and other hard substances:
  also Glaziers' Diamonds. J. DICKINSON, 64 Nassau St., N. Y.
  ----------------------------------------------------------------------
                         =SECOND-HAND ENGINES,=

                Portable and Stationary, at Low Prices.

  HARRIS IRON WORKS,                                     TITUSVILLE, PA.
  ----------------------------------------------------------------------
                       HOW TO MAKE A PHONOGRAPH.

  Full Instructions, with Eight Working Drawings, Half Size.
  Construction easy and Inexpensive. These drawings are from an actual
  working Phonograph; they show the sizes, forms, and arrangement of
  all the parts. The explanations are so plain and practical as to
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  successful operation in a very short time. Contained in SCIENTIFIC
  AMERICAN SUPPLEMENT NO. =133.= Price 10 cents. To be had at this
  office and of all newsdealers.
  ----------------------------------------------------------------------
  [Illustration:
               SCHLENKERS AUTOMATIC REVOLVING BOLT CUTTER
                    DIAMOND SELF CLAMP PAPER CUTTER
                       HOWARD'S SAFETY ELEVATORS
                         HOWARD'S PARALLEL VISE
                    HOWARD IRON WORKS BUFFALO N. Y.
  ]
  ----------------------------------------------------------------------
                              =_PERFECT_=
                            =NEWSPAPER FILE=

  The Koch Patent File, for preserving newspapers, magazines, and
  pamphlets, has been recently improved and price reduced. Subscribers
  to the SCIENTIFIC AMERICAN and SCIENTIFIC AMERICAN SUPPLEMENT can be
  supplied for the low price of $1.50 by mail, or $1.25 at the office
  of this paper. Heavy board sides; inscription "SCIENTIFIC AMERICAN,"
  in gilt. Necessary for every one who wishes to preserve the paper.

  Address
                              =MUNN & CO.,
                                        Publishers SCIENTIFIC AMERICAN.=
  ----------------------------------------------------------------------
                            THE TANITE CO.,
                            STROUDSBURG, PA.
                      =EMERY WHEELS AND GRINDERS.=
             GEO. PLACE, 121 Chambers St., New York Agent.
  ----------------------------------------------------------------------
  [Illustration:
                         ROCK DRILLING MACHINES
                                  AND
                           AIR COMPRESSORS.

                MANUFACTURED BY BURLEIGH ROCK DRILL CO.

                  SEND FOR PAMPHLET. · FITCHBURG MASS.
  ]
  ----------------------------------------------------------------------
                             =STEAM PUMPS.=

                         HENRY R. WORTHINGTON,

  239 Broadway, N. Y.                              83 Water St., Boston.

  THE WORTHINGTON DUPLEX PUMPING ENGINES FOR WATER WORKS--Compound,
  Condensing or Non-Condensing. Used in over 100 Water-Works Stations.

  STEAM PUMPS--Duplex and Single Cylinder.

  WATER METERS. OIL METERS.

                         =Prices largely Reduced.=
  ----------------------------------------------------------------------
  [Illustration: WATSONS NON CHANGEABLE GAP LATHE HAS GREAT
  FACILITIES FOR LARGE OR MEDIUM SIZE WORK JAMES WATSON MANR. 1608
  S. FRONT ST. PHILA. PA.]
  ----------------------------------------------------------------------
                                HARTFORD
                              STEAM BOILER
                         Inspection & Insurance
                                COMPANY.
            W. B. FRANKLIN V. Pres't.   J. M. ALLEN, Pres't.
                          J. B. PIERCE, Sec'y.
  ----------------------------------------------------------------------
  [Illustration]

                     =Patent Portable Chuck Jaws.=

  Improved Solid Emery Wheels, for grinding Iron and Brass Castings,
  Tools, etc. Manufactured by AM. TWIST DRILL CO., Woonsocket, R. I.
  ----------------------------------------------------------------------
  =$7= A DAY to Agents canvassing for the =Fireside Visitor=. Terms and
       Outfit Free. Address P. O. VICKERY, Augusta, Maine.
  ----------------------------------------------------------------------
  =HAND SAW MILL= SAVES THREE MEN'S labor.
                                     S. C. HILLS, 78 Chambers St., N. Y.
  ----------------------------------------------------------------------
                                 =BEST=

                           DAMPER REGULATORS

                       AND WEIGHTED GAUGE COCKS.

             MURRILL & KEIZER, 44 HOLLIDAY ST., BALTIMORE.
  ----------------------------------------------------------------------
  [Illustration: PATENTS]

                =CAVEATS, COPYRIGHTS, TRADE MARKS, ETC.=

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                             =MUNN & CO.=,
                    Publishers SCIENTIFIC AMERICAN,
                                                    37 Park Row, N. Y.

  _BRANCH OFFICE--Corner of F and 7th Streets, Washington, D. C._
  ----------------------------------------------------------------------
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       *       *       *       *       *

TRANSCRIBER'S NOTES

Obvious punctuation errors have been corrected.

Spelling inconsistencies have been retained.

On page 83, the clause "It has an independent extinguisher for the
smaller wick tube" had "ndependent" in the original.

On page 91, the ad reading "The Turbine Wheel made by Risdon & Co., Mt.
Holly, N. J., gave the best results at Centennial tests." had "tets" in
the original.

On page 92, the patent named "Gas, scintillator for lighting" was
numbered "204,28" in the original. The final "5" has been added because
sorting the list reveals that the patent numbers form a consecutive
series from 204,122 to 204,413, with the only one missing being 204,285.

On page 92, the patent named "Shoetip" was guessed at; the "t" is
unclear in the original.

On page 94, the phrase "Alcohol Oxidized in the System." had no
terminating punctuation in the original.

On page 94, the illustration containing the words "Diamonds and
Carbor", the "Carbor" may be an abbreviation for "Carborundum"; the
image is unclear in the original.

On page 94, in the advertisement for "WATSONS [sic] NON [sic] CHANGEABLE
GAP LATHE", the abbreviation "MANR." had the "R" as a superscript in the
original.