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SCIENTIFIC AMERICAN SUPPLEMENT NO. 623




NEW YORK, DECEMBER 10, 1887

Scientific American Supplement. Vol. XXIV., No. 623.

Scientific American established 1845

Scientific American Supplement, $5 a year.

Scientific American and Supplement, $7 a year.

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TABLE OF CONTENTS.


I.    ARCHITECTURE.--Notes on the Construction of a Distillery
      Chimney--A new method of building lofty shafts, including a
      metallic frame and brick lining--3 illustrations.             9949

      The Commercial Exchange, Paris--The new Paris exchange now
      in process of erection.--Present state of operations--1
      illustration.                                                 9954

II.   ASTRONOMY.--The Yale College Measurement of the Pleiades.--
      Dr. Elkin's work with the Repsold heliometer at Yale College. 9957

III.  CHEMISTRY--New Method for the Quantitative Determination
      of Starch.--By A.N. ASBOTH--Determination of starch by its
      barium compound.                                              9956

      Synthesis of the Alkaloids--A retrospect of the field of
      work so far traveled over by synthetical chemists, and
      future prospects.                                             9956

      The Chemical Basis of Plant Forms--By HELEN C. DE S. ABBOTT
      --Continuation of this important contribution to plant
      chemistry, one of the most valuable of recent chemical
      monographs.                                                   9955

IV.   ELECTRICITY.--An Electrical Governor--A new apparatus for
      preserving a constant electromotive force with varying
      dynamo speed--1 illustration.                                 9952

      Electric Launch--A French government launch with Krebs
      electric motor.                                               9954

      The electric current as a means of increasing the tractive
      adhesion of railway motors and other rolling contacts.--By
      ELIAS E. RIES--A full review of this important subject, with
      accounts of its experimental examination.                     9953

V.    ENGINEERING--Benier's Hot Air Engine--A new caloric engine
      very fully illustrated and described--8 illustrations.        9943

      Heating Marine Boilers with Liquid Fuel--A simple apparatus
      and recent experiments with the same.--3 illustrations.       9945

      The Change of Gauge of Southern Railroads in 1886--By C.H.
      HUDSON.--The conclusion of the account of this great
      engineering feat, with tables of statistics and data--16
      illustrations.                                                9946

      Your Future Problems--By CHAS. E. EMERY--An address to
      the graduating class of the Stevens Institute, N.J.--A
      practical view of the engineering profession.                 9943

VI.   MISCELLANEOUS--A Group of Hampshire Downs--A typical
      breed of sheep, their qualities and habits.--1 illustration.  9957

VII.  NAVAL ENGINEERING--The Spanish Cruiser Reina Regente--A
      further description of this celebrated vessel--4
      illustrations.                                                9948

      Torpedo Boats for Spain--The Azor and Halcon, two Yarrow
      torpedo boats, described and illustrated--7 illustrations.    9947

VIII. PHOTOGRAPHY--How Different Tones in Gelatino-chloride Prints
      may be Varied by Developers.--Twenty different formulæ for
      the above purpose.                                            9949

      Film Negatives--Eastman stripping films, their manipulation
      and development.                                              9949

IX.   SANITATION--French Disinfecting Apparatus--A portable
      apparatus for disinfecting clothes and similar objects--1
      illustration.                                                 9952

X.    TECHNOLOGY.--The Manufacture of Cocaine--The extraction
      of cocaine with alkali and petroleum, with statement of
      percentage yielded by various leaves.                         9954

      The Production of Oxygen by Brin's Process--The commercial
      manufacture of oxygen by means of baryta--3 illustrations.    9950


#Transcriber's Note: Following entry not in original table of contents#

      Deep Sea Dredgings: Examination Of Sea Bottoms. By THOMAS     9958
      T.P. BRUCE WARREN.

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BENIER'S HOT AIR ENGINE.


The hot air engine, although theoretically recognized for some time
past as the most economical means of converting heat into motive
power, has up to the present met with little success. This is due to
the fact that the arrangement of the motors of this class that have
hitherto been constructed has been such as to render them but slightly
practical. In the Benier hot air engine (illustrated herewith),
however, obstacles that were once considered insurmountable have been
overcome, and the motor presents many advantages over all the types
that have preceded it. Among such advantages we shall cite the
possibility of utilizing air at a high temperature (1,200 or 1,500
degrees), while the rubbing surfaces remain at a moderate temperature
(60 or 80 degrees). The fire grate is placed in the interior of the
cylinder, and is traversed by the cold air forced by a pump. The
expanded hot gases fill the cylinder and act against the piston
directly above the grate.

The type herewith illustrated is of 6 horse power. The motive
cylinder, CC', is bolted to the extremity of the frame, A. Upon this
latter is fixed a column, B, which carries a working beam, E. This
latter transmits the motion of the piston, P, to the shaft, D. A pump,
G, placed within the frame, forces a certain quantity of cold air at
every revolution into the driving cylinder. The piston of this pump is
actuated by the connecting rod, G', jointed to the lever, F', which
receives its motion from the rod, F. A slide valve, _b'_, actuated by
a cam, regulates the entrance of the cold air into the pump during
suction, as well as its introduction into the cylinder. There is a
thrust upon the piston during its upward travel, and an escape of hot
gas through the eduction valve, _h_, during the downward travel.

The cylinder is in two parts, C and C'. The piston, which is very
long, rubs at its upper end against the sides of the cylinder, C. The
lower end is of smaller diameter, and leaves an annular space between
it and the cylinder. The grate is at the bottom of the cylinder, C'.
The sides of the cylinder at the level of the fire box are protected
with a lining of plumbago. When the piston is at the bottom of its
travel, the eduction valve closes. The slide valve, _b'_, establishes
a communication between the pump chamber and the cylinder. The air
contained in the pump is already compressed in the latter to a
pressure of nearly a kilogramme at the moment of the communication.
This air enters the cylinder, and the communication between the latter
and the pump continues until all the air is forced into the driving
cylinder, the piston of the pump being at the bottom of its travel,
and that of the cylinder about midway.

[Illustration: BENIER'S HOT AIR ENGINE.]

The air forced by the pump piston enters the cylinder through two
conduits, one of which leads a portion of it toward the top of the
cylinder, and the other toward the bottom. The lower conduit debouches
under the grate, and the air that passes through it traverses the fire
box, and the hot gas fills the cylinder. The conduit that runs to the
top debouches in the cylinder, C, at the lower limit of the surface
rubbed by the piston. The air that traverses this conduit is
distributed through the annular space between the piston and cylinder.
The hot gas derived from combustion can therefore never introduce
itself into this annular space, and consequently cannot come into
contact with the rubbing surfaces of the cylinder and piston.

As the quantity of air introduced at every stroke is constant, the
work developed at every stroke is varied by regulating the temperature
of the gas that fills the cylinder. When the temperature falls, the
pressure, and consequently the work developed, diminishes. This result
is obtained by varying the respective quantities of air that pass
through the fire box and around the piston. In measure as less air
passes through the fire box, the quantity that passes around the
piston augments by just so much, and the pressure diminishes. A valve,
_n'_, in the conduit that runs to the fire box is controlled by the
regulator, L', in the interior of the column. When the work to be
transmitted diminishes, the regulator closes the valve more or less,
and the work developed diminishes.

The coke is put by shovelfuls into a hopper, I. Four buckets mounted
upon the periphery of a wheel, I', traverse the coke, and, taking up a
piece of it, let it fall upon the cover, J, of the slide valve, _j_,
whence it falls into the cavity of the latter when it is uncovered,
and from thence into the conduit, _c'_, of the box, _j'_, when the
cavity of the valve is opposite the conduit. From the conduit, _c'_,
the coke falls upon the grate.

A small sight hole covered with glass, in the cover, J, permits the
grate to be seen when the cavity of the valve is opposite _c'_.

As in gas engines, a current of water is made to flow around the
cylinder, C', in order to keep the sides from getting too hot.

In order to set the engine in motion, we begin by opening the bottom,
C, of the cylinder, C', to clean the grate. This done, we close C and
introduce lighted charcoal through the conduit, _c'_ (the valve being
open). The valve is put in place, two or three revolutions are given
to the fly wheel, and the motor starts. The feeding is afterward done
with coke.

The parts that transmit motion operate under conditions analogous to
those under which the same parts of a steam engine do. The air pump
sucks and forces nothing but cold air, and nothing but cold air passes
through the distributing slide valve. The pump and valve are therefore
rendered very durable. The piston and cylinder, at the points where
friction exists, are at a temperature of 60 or 80 degrees. These
surfaces are protected against hot gas charged with dust.

The hot gas, which escapes from the cylinder through a valve, has
previously been cooled by contact with the sides of the cylinder and
by expansion. The eduction valve just mentioned works about like that
of a steam engine, and it is only necessary to polish it now and then
in order to keep it in good condition.--_Annales Industrielles._

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YOUR FUTURE PROBLEMS.[1]

  [Footnote 1: An address to the graduating class, Stevens
  Institute, Hoboken, N.J., 1887.]

By CHARLES E. EMERY.


_Mr. President and Ladies and Gentlemen:_ It has not been considered
the duty of the speaker, in addressing the graduating class, to dwell
on the triumphs of science or the advantage of a liberal education.
These subjects have already been discussed, in connection with the
regular courses of study, better, and more at length, than he could
do. We propose rather to try and prepare the minds of the graduates
for the practical problems before them.

All young men are impressed with the consciousness of higher powers as
they increase their stores of knowledge, and this feeling perhaps
reaches its maximum with those who have made a specialty of the
investigation and application of physical laws. Young men who have
learned how to harness the powers of nature and guide them to do their
will are apt to belittle the difficulties they have yet to overcome,
and have a false impression of the problems of life. This feeling is
shown to a minimum extent by graduates of the Stevens Institute, on
account of their careful practical training, in connection with the
thorough study of principles; but it has been thought best for one
from the outside world to supplement such teaching by calling to mind
instances which may have a useful counteracting effect, and, like
parables, serve the purpose of illustrative instruction.

_Gentlemen of the Class of '87_: It was the pleasure of the speaker to
address the class of '79, under the title of "How to Succeed," some
words of counsel and warning, which, if they left an impression of
severity at the time, were apparently so well received afterward that
he has been tempted to continue the general subject, with the title of
"Your Future Problems." The notation of your future problems will not
be found at once among the known quantities, but with _x_, _y_, and
_z_, at the other end of the alphabet. Often word symbols will be
applicable, expressing at times disappointment and pain, at other
times renewed effort, and finally the active phases of individual
thought and exertion.

The first serious problem with many of you will be to secure
satisfactory engagements. This problem cannot be illustrated by
parables. It needs, in general, patient, unremitting, and frequently
long continued effort. It may be that the fame of some of you, that
have already acquired the happy faculty of making yourselves
immediately useful, has already gone abroad and the coveted positions
been already assured. To be frank, we cannot promise you even a bed of
roses. We have in mind an instance where a superior authority in a
large business enterprise who had great respect, as he should have,
for the attainments of young gentlemen who have had the opportunities
of a technical education, deliberately ordered out a competent
mechanical engineer, familiar with the designs required in a large
repair shop, and sent in his place a young gentleman fresh from school
and flushed with hope, but who from the very nature of the case could
know little or nothing of his duties at that particular place. He was
practically alone in the drawing room, and did not know where to find
such drawings as were required, and candor requires it to be said that
he desired to ask many questions about those he did find. The
superintendent unfortunately had nothing to do with his appointment,
and rather resented it. So he did not trust any of his work, and the
new comer was obliged to learn his practical experience at that
establishment, where he was known as the mechanical engineer, by
having all his work done over by the pattern maker or others, under
the eye of the superintendent or master mechanic, and be subjected all
the time to the jealousies and annoyances incident to such a method of
introduction.

His practical experience was certainly learned under difficulties
which I trust none of you may experience. This statement is made that
those of you who have not yet obtained positions may not envy those
who have, and that each and all of you may be careful not to take a
position so far above your experience, if not your capacity, as to
become unpleasantly situated in the beginning. The educational
facilities you have enjoyed are of such great value in some
exceptional cases that the parties thus benefited may do you an injury
by leading others to expect that you will be equally valuable in
performing duties which require much more practical experience and
knowledge of detail than it is possible that you could have obtained
in the time you have been here.

The incident is ripe with suggestions. No matter how humble a position
you may take in the beginning, you will be embarrassed in much the
same way as the young gentleman in question, though it is hoped in a
less degree. Your course of action should be first to learn to do as
you are told, no matter what you think of it. And above everything
keep your eyes and ears open to obtain practical knowledge of all that
is going on about you. Let nothing escape you of an engineering
nature, though it has connection with the business in hand. It may be
your business the next day, and if you have taken advantage of the
various opportunities to know all about that particular matter in
every detail, you can intelligently act in relation to it, without
embarrassment to yourself and with satisfaction to your superior.

Above all, avoid conflict with the practical force of the
establishment into which you are introduced. It is better, as we have
at another time advised, to establish friendly relations with the
workmen and practical men with whom you have to do.

You are to be spared this evening any direct references to the
"conceit of learning," but you are asked and advised to bear with the
_conceit of ignorance_. You will find that practical men will be
jealous of you on account of your opportunities, and at the same time
jealous of their own practical information and experience, and that
they may take some pains to hinder rather than aid you in your
attempts to actively learn the practical details of the business. The
most disagreeable man about the establishment to persons like you, who
perhaps goes out of his way to insult you, and yet should be respected
for his age, may be one who can be of greatest use to you. Cultivate
his acquaintance. A kind word will generally be the best response to
an offensive remark, though gentlemanly words of resentment may be
necessary when others are present. Sometimes it will be sufficient to
say, "I wish a little talk with you by yourself," which will put the
bystanders at a distance and enable you to mature your plans.
Ascertain as soon as possible that man's tastes; what he reads and
what he delights in. Approach him as if you had no resentment and talk
on his favorite topic. If rebuffed, tell a pleasant story, and persist
from time to time in the attempt to please, until his hardened nature
relaxes and he begins to feel and perhaps speaks to others favorably
of you. St. Paul has said: "For though I be free from all men, yet
have I made myself servant of all that I might gain the more." This is
the keynote of policy, and though in humbling yourself you control and
hide your true feelings, recollect that all your faculties are given
you for proper use.

We have referred to some who have acquired the happy faculty of making
themselves immediately useful. This is a much more difficult matter
than the words imply. If one of you should be so fortunate as to be
ordered to make certain tests almost like those you have already
conducted here, or to tabulate the results of tests as you have done
it here, or to make inspections akin to those which have been fully
explained here, there is every probability the work would be done
satisfactorily in the first instance. But let a much _simpler_ case
arise, for instance, if a superior hand one of you a letter with the
simple instructions, "Get me the facts on that," you may be very much
puzzled to know what is to be done and how to do it. It may be that
the letter is a request for information in regard to certain work that
was carried on in the past, in which case it will be necessary for you
to hunt through old records, copy books, engineering notes, drawings,
and the like, and get a list of all referring to the subject; to make
an abstract of the letters and notes if they are at all complicated;
and finally to lay the whole before the overworked superior in a
business manner, that he largely from recollection, aided by the
references and notes, can write an intelligent answer in a very brief
period. The way not to do it would be to say, "Yes, sir," very
promptly, go off and not more than half read the letter, do something
and be back in five minutes with some question or ill-digested answer;
then upon receiving a polite hint as to the method to be employed, go
off and repeat the operation the next five minutes; then on receiving
a short reply, in what appeared to be an unnecessary tone of voice,
get a little flurried perhaps, do worse next time, and in the end feel
very unpleasant without having accomplished much, and make the
gentleman seeking assistance lament the difficulty in teaching young
men practical work.

It is possible, on the contrary, for a young man to exceed his
instructions and volunteer advice that has not been asked. If he has
unfortunately gone too far for some time and been sharply spoken to,
he may fail the next in not fully doing the work intended. Simply
putting down a column of figures would not necessarily mean tabulating
facts. The arrangement and rearrangement of the columns aid in
classifying such facts, so that the results shown by them will be
readily seen and a great deal of labor saved in examination. A good
rule in a case of this kind is to try and find some work done by other
parties of a similar nature, and thereby ascertain what is needed and
expected. Reasonable questions to ascertain, where records are to be
found and the kind of records accessible, are always proper if made at
the proper time without interrupting an immediate train of thought;
and with such information as a start, if a young man will endeavor to
imagine himself in a place like that of the one who has finally to
decide, and try to ascertain just what information will probably be
required, then patiently go to work to find and present it in
condensed shape, he from that moment really begins to be useful and
his services will be rapidly appreciated. It is a good rule always to
keep the memoranda obtained in accomplishing a result of this kind; so
that if further information is required, the whole investigation need
not be made over.

This remark suggests another line of thought. Some young men with
quick perceptions get in the way at school of trusting their memories,
and omit making complete notes of lectures or of the various tests
illustrating their studies. This carelessness follows them into after
life, and there are instances where young men, who can make certain
kinds of investigations much better than their fellows, and promptly
give a statement of the general nature of the results, have, when
called on afterward for the details, forgotten then entirely, and
their notes and memoranda, if preserved, being of little use, the
labor is entirely lost. Such men necessarily have to learn more
careful ways in after life. It is a good rule in this, as in the
previous case, to make and copy complete records of everything in such
shape that they may be convenient for reference and criticism
afterward.

One of the important problems with which you will have to deal in the
future is the labor question, and it is probable that your very first
experience with it may be in direct antagonism with the opinions of
many with whom you have heretofore been associated. It is an honor to
the feelings of those who stand outside and witness this so-called
struggle now in progress between capital and labor, that they believe
the whole question can be settled by kindly treatment and reasonable
argument. There are some cases that will yield to such treatment, and
one's whole duty is not performed till all possible, reasonable, and
humanitarian methods are adopted. There has been an excuse for the
organization of labor, and it, to some small extent, still exists.

Time was that the surplus of unskilled labor was used on a mercantile
basis to reduce wages to such an extent that it was almost impossible
to rear a well nurtured, much less a well educated and well dressed
family, and, moreover, the hours of labor in some branches of business
were so long as to shorten the lives of operatives and make
self-improvement impossible. The natural progress of civilizing
influence did much to abate many of these evils, but the organization
of labor removed sores that had not and perhaps could not have been
reached in other ways. Having then an excuse for organization, and
supported by the success made in directions where public sympathy was
with them, is it to be wondered that they have gone too far in very
many cases, and that the leadership of such organization has in many
instances been captured by designing men, who control the masses to
accomplish selfish ends? Whatever may have been the method of
evolution, it is certain that the manufacturing operations of the
present day have to meet with elements entirely antagonistic to their
interests, and in very many ways antagonistic to the interests of the
workingman. The members of many organizations, even of intelligent
men, are blindly led by chiefs of various titles, of which perhaps the
walking delegate is the most offensive one to reasonable people. This
class of men claim the right to intrude themselves into the
establishments owned by others, and on the most trivial grounds make
demands more or less unreasonable, and order strikes and otherwise
interfere with the work of manufacturers, much in the way that we have
an idea that the agents of the barbarbous chieftains, feudal lords,
and semi-civilized rulers collected taxes and laid burdens in earlier
historical times. Necessarily these men must use their power so as to
insure its permanency. If strikes are popular, strikes must be
ordered. If funds run low, excuses for strikes, it is believed, in
many cases are sought, so as to stir the pulses of those who
sympathize with the labor cause.

Co-operation has been suggested as a cure for the evil, and there are
cases where it has apparently succeeded, in connection with the
earlier forms of labor organization. The ambition of later labor
leaders almost prevents this remedy being of effect. It may be
possible still with very intelligent workmen, isolated from the large
mass of workmen in the country towns, to feel an interest in
co-operation; but such inducements, or the higher ones of personal
kindness to employes or their families, are not of much effect in
large manufacturing centers. As soon as dissatisfaction exists in one
mill or manufactory, all similar employes are ordered out. The final
result will be that combinations of employers must follow the
combination of employes, and those who have always been strong in the
past will be stronger in the future, as has appeared to be the case in
many contests that have already taken place. If there are any real
abuses of power by the employers, such as requiring work for unusual
hours or at less than living rates, the first thing to do is to
correct these abuses, so that complaints will not be upon a sound
foundation. Some men, when the labor epidemic strikes their places,
have sufficient force of character and influence with their men to
avert the blow for some time. Others find it is policy to compromise
with the representatives until a plan of action, conciliatory,
offensive, or defensive, can be determined upon. The whole matter must
be considered one of policy rather than of principles. The class of
men to be dealt with do not talk principles except as an excuse to
secure their ends.

In spite of everything, there will be times when no compromise is
possible and you will be called upon to take part in defending your
employers' interests against what is called a "strike." You can do so
with heart when you know the employes are all well paid, and
particularly, as is frequently the case, when the labor organizers and
walking delegates claim that some old, tried foreman shall be
dismissed because they do like him, really because he has not been a
tool in carrying out their plans, and they defiantly acknowledge that
their war is against non-union labor, and that they have organized
your men and forced a strike to require your establishment to become
as it is called a "union shop." If your deluded employes were
permitted simply to go away and let you alone, and you were permitted
to employ others at the reasonable wages you were paying, the problem
would be a simple one. The principal labor organizations claim that
everything they do is by peaceable methods, but this, like many things
said, is simply to deceive, for if you attempt to employ other
assistants and carry on your business independently, you will surely
find that well known roughs are assembled who never do anything
without they are paid for it by somebody, that your men are assaulted
by such persons, and while the labor organizers talk about peaceable
methods and urge them aloud in public, in case one of the roughs is
arrested, the loud talkers are the first to go bail for the defender,
and you will feel morally sure that the sympathizing crowd with the
roughs who make the assaults are all part of or tools of the
organization.

At such times, you will find your old employes standing around the
street corners, persuading other men not to go to work and thus
interfere with what are called the true interests of labor. Any new
employe who has to go in the street will be first met with inducements
of other employment, with offers of money, afterward with threats,
and, if opportunity occurs, with direct assault. All the features of
persuasion, intimidation, and violence will be carried out as
demanded, and strangers to everybody in the vicinity, but well known
as experienced leaders in this kind of work in other places, be
brought in to endeavor to make the strike a success. Then, young men,
is the time to show your pluck, and our experience is that educated
young men will do so every time. They can be depended upon to go
straight ahead with duty through every danger, bearing patiently
everything that may be said, defending themselves with nature's
weapons as long as possible, and without fear using reserve weapons in
case real danger of life is imminent.

In carrying through a very important strike against a mere desire to
control and not to correct abuses, your speaker desires to pay the
highest tribute to a number of educated young men, mostly from the
technical schools, who fearlessly faced every danger, and by their
example stimulated others to do their duty, and all participated in
the results obtained by a great success.

We would not by such references fire your hearts to a desire to
participate in such an unpleasant contest. It is the duty of all to
study this problem intelligently and earnestly, with a view of
overcoming the difficulties and permitting the prosperity of the
country to go on. While conciliation may be best at some times, policy
at another, and resistance at another, we must also be thinking of the
best means to prevent further outbreaks. It would seem to be true
policy not to interfere with organization, but to try and direct it
into higher channels. Those of the humanitarians who claim that the
disease will be rooted out eventually by a more general and better
education are undoubtedly largely in the right, notwithstanding that
some fairly educated men have acted against their best interests in
affiliating with the labor organizations. It seems to the speaker that
enough instances can be collected to show the utter folly of the
present selfish system, based, as it is, entirely on getting all that
is possible, independent of right in the matter, and by demanding
equal wages for all men, tending to lower all to one common
degradation, instead of rewarding industry and ability and advancing
the cause of civilization.

Labor should not be organized for selfish ends, but for its own good,
_so as to secure steady and permanent employment_, rather than prevent
it by impracticable schemes and unwise methods, which will cripple
manufacturers and all kinds of industry. The men should organize under
the general laws of the State, so that their leaders will be
responsible to the laws and can be indicted, tried, and punished in
case they misappropriate funds or commit any breach of trust; and such
laws should be amended if necessary, so that wise, responsible leaders
of the organizations can contract to furnish labor for a certain time
at a fixed price, when manufacturers can make calculations ahead as to
the cost of labor the same as for the cost of material, and have such
confidence that they will use all their energies to do a larger amount
of business and benefit the workingman as well as themselves by
furnishing steady employment. Such a plan as is here outlined can
readily be carried into effect by selecting better men as leaders. It
is well known how well the organization known as the locomotive
brotherhood is conducted, and it should be an example to others. It
has had its day of dissensions, when the best counsels did not
prevail, which shows that any organization of the kind, no matter how
well conducted, may be diverted by its leaders into improper channels.

When organized under the laws of the State and under by-laws designed
to secure steady employment, rather than any artificial condition of
things in regard to pay hours, and continuance of labor, the true
interests of the workman will be advanced. It may be that some one of
you will develop a talent in the direction of organization and be the
means of aiding in the solution of this great problem. Please think of
the matter seriously, watch the law of evolution while you are
advancing your professional knowledge, and if the opportunity offers,
do all you can to aid in a cause so important and beneficent.

One writer has criticised the technical schools because they do not
teach mechanical intuition. The schools have enough to do in the time
available if they teach principles and sufficient practice to enable
the principles to be understood. The aptitude to design, which must be
what is meant by mechanical intuition, requires very considerable
practical experience, which you will readily learn if you do not keep
yourself above it. If you have used your leisure hours to study why a
certain piece of mechanism was made in a certain way rather than in
another; if you have wondered why one part is thick in one place
rather than in another, apparently in defiance of all rules of the
strength of material; if you have endeavored to ascertain why a
particular device is used rather than another more evident one; if you
have thought and studied why a boss is thrown in here and there in
designs to receive bolts or to lengthen a journal, and if you have in
your mind, by repeated observation, a fair idea of how work is
designed by other people, the so-called _mechanical intuition_ will be
learned and found to be the _combination of common sense and good
practice_.

You will observe that some details have been copied for years and
years, although thoughtful men would say they are not the best, simply
because they are adapted to a large amount of work already done. This
is particularly true of the rolling stock on railroads. The cost of a
change in starting in a new country might be warranted, but it
practically cannot be done when the parts must interchange with so
much work done in other parts of the country. You will find in other
cases that the direct strain to which a piece of mechanism is
subjected is only one of the strains which occur in practice. A piece
of metal may have been thickened where it customarily broke, and you
may possibly surmise that certain jars took place that caused such
breakages, or that particular point was where the abuse of the
attendant was customarily applied.

Wherever you go you will find matters of this kind affecting designs
staring you in the face, and you will soon see why a man who has
learned his trade in the shop, and from there worked into the drawing
room with much less technical information than you have, can get along
as well as he does. Reserve your strength, however. Your time will
come. Whenever there is a new departure to be taken, and matters to be
worked out from the solid which require close computation of strains
or the application of any principles, your education will put you far
ahead, and if you have, during the period of what may be called your
post-graduate course, which occurs during your early introduction into
practical life, been careful to keep your eyes and ears open so as to
learn all that a man in practical life has done, you will soon stand
far ahead.

Reference was made to the use of leisure hours. Leisure hours can be
spent in various ways. For instance, in studying the composition and
resolution of forces and the laws of elasticity in a billiard room,
the poetry of motion, etc., in a ball room, and the chemical
properties of various malt and vinous extracts in another room; but
the philosophical reason why certain engineering work is done in the
way it is, and the proper way in which new work shall be done of a
similar character and original work of any kind carried on, can only
be learned by cultivating your powers of observation and ruminating on
the facts collected in the privacy of one's own room, away from the
allurements provided for those who have nothing to do. No one would
recommend you to so separate yourself from the world as to sacrifice
health and strength, or to become a recluse, even if you did learn all
about a certain thing.

Remember, however, that the men who have accomplished most in this
world worked the longest hours, and any one with a regular occupation
must utilize his leisure hours to obtain prestige. The difference
between one man and another of the same natural ability lies entirely
in the amount of his information and the facility with which he can
use it. Life is short, and you must realize that now is your
opportunity. If any diversion in the way of pleasure or even certain
kinds of congenial work is offered, consider it in connection with the
question, "Will this be conducive to my higher aim?" This implies that
you have a higher aim; and if you have it, and weigh everything in
this way, you will find that every moment of exertion adds something
to your storehouse of information and brings you nearer to the
accomplishment of that higher aim.

In closing, we thank the ladies and gentlemen present for their close
attention to details of special interest only to those engaged in
technical study or practice.

We congratulate you, young gentlemen of the class of '87, for the
success you have thus far obtained, and trust that you will persevere
in well doing and win greater success in the future. We need hardly
state that all that has been said was in a spirit of kindness, and we
feel assured that much of it has been seconded by your parents, to
whom no less than to all parents here present off or on the stage, the
speaker not excepted, a serious, thoughtful problem has been, still
is, and will continue to be to many, "What shall we do with our
boys."--_Stevens Indicator._

       *       *       *       *       *




HEATING MARINE BOILERS WITH LIQUID FUEL.


We were recently witness of an experiment made at Eragny Conflans on
the steam yacht Flamboyante. It was a question of testing a new
vaporizer or burner for liquid fuel. The experiment was a repetition
of the one that the inventor, Mr. G. Dietrich, recently performed with
success in the presence of Admirals Cloue and Miot.

The Flamboyante is 58 ft. in length, 9 ft. in width, draws 5 ft. of
water, and has a displacement of 10 tons. She is provided with a
double vertical engine supplied by a Belleville boiler that develops
28 horse power. The screw makes 200 revolutions per minute, and gives
the yacht a speed of 6½ knots.

Mr. Dietrich's vaporizer appears to be very simple, and has given so
good results that we have thought it of interest to give our readers a
succinct description of it. In this apparatus, the inventor has
endeavored to obtain an easy regulation of the two essential
elements--naphtha and steam.

Fig. 1 represents the apparatus in section. The steam enters through
the tubulure, A, and finds its way around the periphery of a tuyere,
D. It escapes with great velocity, carries along the petroleum that
runs from two lateral tubulures, B (Fig. 2), and throws it in a fine
spray into the fireplace, through the nozzle, C (Fig. 1), which is
flattened into the shape of a fan opened out horizontally. The mixture
at once ignites in contact with the hot gases, and gives a beautiful,
long, clear flame. The air necessary for the combustion is sucked
through the interior of the nozzle, H, which is in front of the
tuyere. It will be seen that the current of steam can be regulated by
moving the tuyere, D, from or toward the eduction orifice. This is
effected through a maneuver of the hand wheel, F. In the second place,
the flow of the petroleum is made regular by revolving the hand wheel,
G, which gives the piston, O, a to and fro motion in the tuyere, D.

[Illustration: FIG. 1--THE DIETRICH PETROLEUM BURNER.]

The regulation may be performed with the greatest ease. It is possible
to instantly vary, together or separately, the steam and the
petroleum. Under such circumstances, choking is not to be feared at
the petroleum orifice, where, according to experiment, the thickness
of the substance to be vaporized should not be less than 0.04 of an
inch.

The petroleum might evidently be made to enter at A and the steam at
B; but one of the conclusions of the experiments cited is that the
performance is better when the jet of steam surrounds the petroleum.
It will be understood, in fact, that by this means not a particle of
the liquid can escape vaporization and, consequently, combustion.
Moreover, as the jet of petroleum is completely surrounded by steam
its flow can be increased within the widest limits, and this, in
certain cases, may prevent an obstruction without much diminishing the
useful effect of the burner.

The apparatus is easily and rapidly taken apart. It it is only
necessary to remove the nozzle, C, in order to partially clean it. It
would even seem that the cleaning might be done automatically by
occasionally reversing the flow of the steam and petroleum. However
efficacious such a method might prove, the apparatus as we have
described it can be very easily applied to any generator. Fig. 2
represents it as applied to the front of a furnace provided with two
doors. A metallic box, with two compartments, is placed on one side of
the furnace, and is provided with two stuffing boxes that are capable
of revolving around the steam and petroleum pipes. The latter thus
form the pivots of the hinge that allows of the play of the vaporizers
and piping.

[Illustration: FIG. 2--THE BURNER APPLIED TO THE FURNACE OF A BOILER.]

It was in this way that Mr. Dietrich arranged his apparatus in an
experiment made upon a stationary boiler belonging to a Mr. Corpet.
The experiment was satisfactory and led to the adoption of the
arrangement shown in Fig. 3. The fire bridge is constructed of
refractory bricks, and the majority of the grate bars are filled in
with brick. The few free bars permit of the firing of the boiler and
of access of air to the interior of the fire box. Under such
circumstances, the combustion is very regular, the furnace does not
roar, and the smoke-consuming qualities are perfect.

[Illustration: FIG. 3--APPLICATION OF THE BURNER TO A RETURN FLAME
BOILER.]

In the experiment on the Flamboyante, the boiler was provided with but
one apparatus, and the grate remained covered with a layer of ignited
coal that had been used for firing up in order to obtain the necessary
pressure of steam to set the vaporizer in operation. This ignited coal
appeared to very advantageously replace the refractory bricks, the
role of which it exactly fulfilled. It has been found well, moreover,
to break the flames by a few piles of bricks in the furnace, in order
to obtain as intimate a mixture as possible of the inflammable gases.

It is to be remarked that firing up in order to obtain the necessary
steam at first is a drawback that might be surmounted by using at the
beginning of the operation a very small auxiliary boiler. The main
furnace would then be fired by means of say a wad of cotton. But, in
current practice, if a grate and fire be retained, the firing will
perhaps be simpler.

With but one apparatus, the pressure in the Flamboyante's boiler rose
in a few minutes from 6 to 25 pounds, and about a quarter of an hour
after leaving the wharf the apparatus had been so regulated that there
was no sign of smoke. This property of the Dietrich burner proceeds
naturally from the use of a jet of steam to carry along the petroleum
and air necessary for combustion. It is, in fact, an Orvis smoke
consumer transformed, and applied in a special way.

It must be added that the regulating requires a certain amount of
practice and even a certain amount of time at every change in the
boat's running. So it is well to use two, and even three, apparatus,
of a size adapted to that of the boiler. The regulation of the furnace
temperature is then effected by extinguishing one or two, or even
three, of the apparatus, according as it is desired to slow up more or
less or to come to a standstill.

The oil used by Mr. De Dosme on his yacht comes from Comaille, near
Antun. The price of it is quite low, and, seeing the feeble
consumption (from 33 to 45 lb. for the yacht's boiler), it competes
advantageously with the coal that Mr. De Dosme was formerly obliged to
use.--_La Nature._

       *       *       *       *       *

[Continued from SUPPLEMENT, No. 622, page 9935.]




THE CHANGE OF GAUGE OF SOUTHERN RAILROADS IN 1886.[1]

  [Footnote 1: A paper read before the Western Society of Engineers,
  June 7, 1887.]

By C.H. HUDSON.


Many of the wheels that were still in use with the long hub were put
into a lathe, and a groove was cut an inch and a half back from the
face, leaving our cast collar, which was easily split off as before.
(Fig. 24.)

With tender wheels, as with our car wheels, the case was different.
Originally, the axle for the 5 ft. gauge was longer than for the 4 ft.
9 in.; but latterly the 5 ft. roads had used a great many master car
builders' axles for the 4 ft. 9 in. gauge, namely, 6 ft. 11¼ in. over
all, thus making the width of the truck the same as for 4 ft. 9 in.
gauge. To do this a dished wheel, or rather a wheel with a greater
dish by 1½ in. than previously used, was needed, so that the tread of
the wheel could be at its proper place. (See Fig. 25.) There were, of
course, many of the wheels with small dish and long axles still in
use. Their treatment, however, when the day of change came, did not
vary from that of the short axle.

[Illustration: FIG. 24 and FIG. 25]

It had been the rule for some years that all axles should be turned
back 1½ in. further than needed; but unfortunately the rule had not
been closely followed, and many were found not to be so turned. To
make the matter worse, quite a number of the wheels were found to have
been counterbored about ½ in. deep at the back end, and the axle
turned up to fit this counterbore; a good idea to prevent the running
in, in case the wheel worked loose, but bad from the standpoint of a
change of gauge. In such cases the wheels had to be started off before
the axle could be turned back, so that the wheels could be pushed on
in their proper position. (Fig. 26.)

[Illustration: FIG. 26]

If the work was done where they had a lathe large enough to swing a
pair of wheels, they were pressed off but half an inch, the wheels
swung in the lathe, the axles turned back 1½ in., and the wheels then
pressed on 2 in. or 1½ in. inside of their first position.

Where no large lathe was in use, the wheels came entirely off before
the axles could be turned back. The work in the former case was both
the quicker and the cheaper. Where the large lathes were used they
were either set down into the floor, so a pair of wheels would easily
roll into place, or a raised platform was put before the lathe, with
an incline up which the wheels were rolled and then taken to the
lathe. These arrangements were found much quicker and cheaper than to
hoist the wheels up, as is usually done.

In pressing the wheels on, where the axles had previously been turned
back, much trouble was at first experienced because of the rust that
had gathered upon the turned part behind the wheel, forming a ridge
over or upon which the wheel must be pushed. Some of the roads, at the
start, burst 10 or 15 per cent. of the wheels so pressed on. By
saturating this surface with coal oil, however, it was found that the
rust was easily removed and little trouble was had. It was found,
sometimes, that upon axles newly turned back a careless workman would
leave a ridge at the starting point of the turning. Frequently also
the axles were a little sprung, so that the new turning would be a
little scant upon one side when compared with the old surface, and
upon the opposite side a little full. As an indication that these
difficulties were overcome as they appeared, I will say that upon our
line only 202 wheels burst out of nearly 27,000 pressed on--an
exceedingly small percentage.

After the change upon the early roads they were troubled for weeks
with hot boxes, caused, as we believed, by the changing of brasses. A
brass once fitted to a journal will work upon it without trouble, but
when placed upon some other journal will probably not fit. If the
journal had been worn hollow (and it was surprising to see how many
were so worn), the brass would be found worn down to fit it. (See Fig.
27. Exaggerated, of course.)

[Illustration: FIG. 27 and FIG. 28]

The next wheel may have an axle worn little or none. (See Fig. 28)

Now, if these brasses are exchanged, we have the conditions as shown
in Figs. 29 and 30, and we must expect they will heat. The remedy was
simply to keep each brass upon its own journal. To do this the brasses
were fastened to the axle by a piece of small wire, and went with it
to the lathe and press. When its truck was reached, the brass was
there with its journal. Worn-out brasses, of course, could not be put
in, and new ones were substituted. The little trouble from that source
that followed the change showed the efficacy of the remedy.

[Illustration: FIG. 29 and FIG. 30]

The manner in which the tires of engines were to be changed, when the
final day came, was a serious question. The old-fashioned fire upon
the ground could not be thought of. The M. & O. had used a fire of
pine under the wheel, which was covered by a box of sheet iron, so
arranged that the flame and heat would be conveyed around the tire,
and out at an aperture at the top. (Fig. 31.) Many thought this
perfect, while others were not satisfied, and began experiments for
something better. A device for using gas had been patented, but it was
somewhat complicated, as well as expensive, and did not meet with
general favor. A very simple device was soon hit upon. A two inch pipe
was bent around in a circle a little larger than the outer rim of the
wheel. Holes 1/10 in. in diameter and 3 or 4 in. apart were drilled
through the pipe on the inside of the circle. To this pipe was
fastened another with a branch or fork upon it. To one branch or fork
was connected a gas pipe from the meter, while to the other was
connected a pipe from an air pump. With the ordinary pressure of city
gas upon this pipe it was found that the air pump must keep an air
pressure of 40 pounds, that the air and gas might mix properly at the
branch or fork, so we could get the best combustion and most heat from
our "blowpipe," for such it was. (Fig. 32.)

[Illustration: FIG. 31 and FIG. 32]

We were able to heat a tire so it could be moved in ten to twenty
minutes, and the machine may be said to have been satisfactory.

Gas, however, was not to be had at all places where it would be
necessary to change tires, and the item of cost was considerable.

To reach a result as good, if possible, experiments were begun with
coal oil (headlight oil). They were crude and unsatisfactory at first,
but soon success was reached.

A pipe was bent to fit the lower half of a wheel pretty closely and
then turned back under itself about the diameter of the pipe distant
from it. This under part had holes 1/10 in. diameter and 3 or 4 in.
apart drilled upon its upper side or under the upper pipe. Connected
with the upper pipe at its center was a pipe which ran to one side and
up to the can containing the kerosene. Between the can and the pipe
under the wheel was a stop cock, by which the flow of oil could be
controlled.

[Illustration: FIG. 33]

To use the device, open the cock and let a small amount of oil flow;
apply fire to the pipe under the wheel, and the oil in the upper pipe
is converted into gas, which flows out of the small holes in the lower
pipe, takes fire, and heats not only the tire, but the upper pipe,
thus converting more oil into gas. We had here a lot of blue flame
jets and the same result as with gas, but at less cost. We had also a
machine that was inexpensive and easily handled anywhere. Boxes were
placed over the upper parts of the wheels, that the heat might pass
closely to the tire. This device was extensively used by our people,
and with great satisfaction. In one way care had to be taken, viz.:
That in starting the fire it did not smoke and cover the tire with
carbon or "lampblack," which is a non-conductor of heat.

Experiments were made with air forced through gasoline, and with oil
heated in a can to form gas. There was more danger in either of these
than with our blowpipe device, and no better results were obtained,
though the cost was greater.

With the change of the wheels, the brakes had to be changed the same
amount, that is, each one set in 1½ in. This it was thought would
either require new hangers or a change in the head or shoe in some
way. We found that the hangers could easily be bent without removal.
Fig. 34 shows three hangers after passing through the bending process.
A short lever arranged to clasp the hanger just below the point, A,
was the instrument; a forked "shore" is now placed, with the fork,
against the point, A, and the other end against the car sill; press
down on the lever and you bend the hanger at A; lower the lever to a
point just below B, reverse the process, and you have the bend at B;
the whole thing taking less than two minutes per hanger. A new bolt
hole, of course, has been bored in the brake beam 1½ in. inside the
old hole. It takes but a short time after this to change the position
of the head and shoe.

[Illustration: FIG. 34]

Before the day of change, a portion of the spikes were drawn from the
inside of the rail to be moved, and spike set 3 in. inside of the
rail. As a rule two spikes were drawn and the third left. At least
every third spike was set for the new gauge, and in some cases every
other one.

There were several devices with which to set the spike. A small piece
of iron 3 in. wide was common, and answered the purpose well. This had
a handle, sometimes small, just large enough for the hand to clasp,
while others had a handle long enough for a man to use it without
stooping down. (See Figs. 35 and 36.) Another device is shown in Fig.
37, so arranged that the measurements were made from the head of the
other rail. This was liked best, and, it is thought, gave the best
results, as the moved rail was more likely to be in good line than
when the measurements were taken from the flange.

[Illustration: FIG. 35, FIG. 36 and FIG. 37]

It was intended that great care should be taken in driving the spikes,
that they were in the proper place, square with the rail, and left
sticking up about an inch.

The ties, of course, were all adzed down before the day of change.

"Handspikes" were originally used to throw the rails, as were lining
bars.

We found, however, that small "cant hooks" were more easily handled
and did better work. The first were made like Fig. 38, with a spike in
the end of a stick, while the hook was fastened with a bolt about 10
or 12 inches above the foot.

[Illustration: FIG. 38 and FIG. 39]

We afterward made them of a 1¼ in. rod, 3½ ft. long, pointed at one
end, with a ring shrunk on 1 ft. from the bottom. Then the hook was
made with an eye, as shown in Fig. 39, which slipped down over the top
of the main rod. This was simple and cheap, and the iron was to be
used for repair purposes when this work was done.

Upon the system with which the writer was connected we had some
branches where we could experiment upon the moving of the rail.
Between Selma and Lauderdale the traffic was light, and at Lauderdale
it connected with the Mobile & Ohio Railroad, which was narrow, and to
which all freight had to be transferred, either by hoisting the cars
or by handling through the house. By changing our gauge we would
simply change the point of transfer to Selma. Here was a chance to
experiment upon one hundred miles and cause little trouble to traffic.
We could see the practical workings of our plans, and, at the same
time, leave less to do on the final day. Upon the 20th of April we did
this work. It had been our plan to do it somewhat earlier, but floods
prevented.

Most of the rail was old chair iron, short, and consequently more time
was used in making the change than would have been required had our
work been on fishplate rail. Our sections here were about eight miles
long, and we arranged our men on the basis blocked out by the
committee, viz., 24 to 26 men to the section, consisting of 6 spike
pullers, 4 throwing rails, 12 spikers, 2 to push the cars and carry
water.

We soon found 5 ft. cars useless, and threw them into the ditch to be
picked up at some future time.

The men were spread out so as not to be in each other's way, and when
the organization was understood and conformed to, it worked well. One
gang changed 5 miles in 5 hours and 10 minutes, including a number of
switches. We found, however, and it was demonstrated still more
strongly on later work, that after 5 or 6 miles the men began to lag.

We believed we had the best results when we had sections of about that
length.

It was arranged that two sections, alternately, commenced work
together at one point, working from each other and continuing until
the force of another section was met, working from the opposite
direction.

The foreman in charge was expected to examine the work and know that
all was right. The push car which followed was a good test as to
gauge.

A work train was started from each end with a small force (20 or 25
men) to run over the changed track. This train, of course, had been
changed on a previous day to be ready for this work.

If a force was overtaken by this train with its work not done, the men
on the train were at once spread out to aid in its completion. This
done, the train ran on.

Not until this was done was a traffic train allowed to pass over the
track. The same rule was followed upon all the work.

Upon the final day it was required that upon all high trestles and in
tunnels the track should be full-spiked before being left or a train
let over. This took extra time and labor, and possibly was not
necessary; but it was a precaution on the side of safety.

Upon the day of the change of the Alabama Central Division (Selma to
Lauderdale), superintendents of other divisions, with their road
masters, supervisors, master mechanics and many section foremen, were
sent over to see the organization and work and the preparations that
had been made. Many of them lent a helping hand in the work. They saw
here in practice what had only been theory before.

About a week before the general change that portion of the road
between Rome, Ga., and Selma, Ala., about 200 miles, was changed, and
again men from other divisions were sent to see and aid in the work.
So when the final day came, the largest possible number of men were
able to work understandingly.

On the last day of May the Memphis & Charleston, Knoxville & Ohio, and
North Carolina branch were changed, and on June 1 the line from
Bristol to Chattanooga and Brunswick.

Other roads changed their branch lines a day or two before the 1st of
June; but the main lines, as a rule, were changed on that day.

It was a small matter to take care of the cars and arrange the train
service so there should be no hitches. It was not expected that
connections would move freight during the 48 hours prior to the
change, and these days were spent in clearing the road of everything,
and taking the cars to the points of rendezvous. All scheduled freight
trains were abandoned on the day prior to the change, and only trains
run _to_ such points.

Upon the East Tennessee system these points were Knoxville, Rome,
Atlanta, Macon, Huntsville, and Memphis, and to these points all cars
must go, loaded or empty, and there they were parked upon the tracks
prepared for the purpose. Passenger trains were run to points where it
had been arranged to change them, generally to the general changing
point.

Most of the Southern roads have double daily passenger service. Upon
all roads one of these trains, upon the day of change, was abandoned,
and upon some all. Some, even, did not run till next day.

We were able to start the day trains out by 10 or 11 o'clock A.M., and
put them through in fair time. Of course, no freights were run that
day, and the next day was used in getting the cars which had been
changed out of the parks and into line. So our freight traffic over
the entire South was suspended practically three days.

The work of changing was to commence at 3:30 A.M., but many of the men
were in position at an earlier hour, and did commence work as soon as
the last train was over, or an hour or so before the fixed time.
Half-past three A.M., however, can be set down as the general hour of
commencement.

For five or six hours in the cool morning the work went on briskly,
the men working with much more than ordinary enthusiasm. But the day
was warm, and after 9 or 10 A.M. it began to lag. All was done,
however, before the day was over, and safe, so that trains could pass
at full speed.

The men all received $1.50 for the work, whether it was finished early
or late in the day, and were paid that afternoon as soon as the work
was done. Tickets were given the men, which the nearest agent paid,
remitting as cash to the treasurer.

On some lines it was deemed best to offer prizes to those who got
through first.

Reports showed some very early finishes. But the facts seem to have
been that under such encouragement the men were apt to pull _too many_
spikes before the change and put _too few_ in while changing. They
were thus reported through early, but their work was not done, and
they took great chances.

It was by most considered unwise to offer such prizes, preferring to
have a little more time taken and be sure that all was safe. Such
lines seemed to get their trains in motion with as much promptness as
others. This, with freedom from accident, was the end sought.

It was found after the work had been done that there had been little
inaccuracies in driving the gauge spike, to which the rail was thrown,
probably from various causes. The rail to be moved may not always have
been exactly in its proper place, and then the template in the hurry
may not have been accurately placed, or the spike may have turned or
twisted.

Whatever was the cause, it was found that frequently the line on the
moved side was not perfect, and, of course, many spikes had to be
drawn and the rail lined up and respiked. The more careful the work
had been done, the less of this there was to do afterward. With rough
track this was least seen. The nearer perfect, the more noticeable it
was.

Of course, we all planned to get foreign cars home and have ours sent
to us. But when the interchange stopped, we found we had many foreign
cars, which, of course, had to be changed. This subject had come up in
convention and it had been voted to charge three dollars per car when
axles did not need turning, and five dollars where they did. By
comparison with the cost of changing, as shown in this paper, it will
be seen that to our company, at least, there was no loss at these
figures.

The following tables will explain the work done upon the Louisville &
Nashville and East Tennessee, Virginia & Georgia systems.

It is to be regretted that the writer has not at hand information
regarding other roads, that fuller statements and comparisons might be
made and the showings be of greater value.

The figures of the Mobile & Ohio are added, having been compiled from
the annual report of that road.


                       MOBILE & OHIO RAILROAD.
                   (_Compiled from Annual Report._)

________________________________________________________________________
                      |        |          |          |          |       |
                      | Number | Cost of  | Cost of  |  Total   |Average|
                      |Changed.|  Labor.  | Material |  Cost.   | Cost. |
                      |________|__________|__________|__________|_______|
                      |        |          |          |          |       |
Engines and tenders.  |   47   |$ 8,031.42|$ 7,276.86|$15,308.28|$325.70|
Pass., bag., ex. cars.|   55   |    439.37|    104.25|    542.62|   9.87|
Freight cars, 1,361. }|1,468½  |  5,719.03|    739.57|  6,458.60|   4.40|
Freight trucks, 107½.}|        |          |          |          |       |
Lever and push cars.  |  143   |  1,427.55|    476.93|  1,904.48|  13.32|
                      |        |          |          |          |       |
                      | Miles. |          |          |          |       |
Track (inc. sidings). |  583.5 | 17,109.53|  7,275.14| 24,384.87|  41.79|
Bridges.              |  583.5 |  1,896.60|    190.00|  2,086.60|   3.58|
Track tools.          |  583.5 |    170.72|  1,405.74|  1,576.46|   2.70|
Shop tools.           |  583.5 |    419.70|  2,982.90|  3,402.60|   5.83|
Temp. side tracks.    |   12.09|  1,958.94|    372.37|  2,331.31| 192.83|
Switching cars.       |        |  1,398.18|     16.50|  1,414.68|       |
Car hoists.           |        |  2,499.38|  4,419.34|  6,918.72|       |
                      |________|__________|__________|__________|_______|
                      |        |          |          |          |       |
  Total cost.         |        |$41,069.42|$25,259.60|$66,329.02|       |
  Total average cost  |        |          |          |          |       |
   per mile.          |        |          |          |          |$113.68|
______________________|________|__________|__________|__________|_______|


                 LOUISVILLE & NASHVILLE RAILROAD.
                 (_Compiled from Annual Report._)


Miles of track--Main line              1,893.7
              --Side track               196.3
                                       -------     2,090.0
                                                              Cost
             Track.                                 Total.  per Mile.
Section labor--Before day of change  $28,106.60
             --On day of change       20,090.42
             --After day of change    19,713.19
                                     ----------  $67,910.21   $32.49
Carpenter labor                                    3,799.19     1.82
Spikes                                            20,873.70     9.99
Switches                                           6,331.85     3.03
Tools                                              2,749.50     1.31
Hand cars and sundries                             5,691.39     2.72
                                                -----------   ------
   Total                                        $107,855.84   $51.36

                         _Equipment._
                                                               Average
                                        Number.      Total.      Cost.
Locomotives                                264   $53,480.98    $202.58
Cars (300 of these passenger--3.5%)      8,537    49,577.20       5.81
                                                -----------   --------
   Total cost                                   $210,414.02
   Total average cost per mile                                 $100.67


             EAST TENNESSEE, VIRGINIA & GEORGIA SYSTEM.

__________________________________________________________________________
                      |         |          |          |           |       |
                      |  Number | Cost of  | Cost of  |   Total   |Average|
                      | Changed.|  Labor.  | Material |   Cost.   | Cost. |
                      |_________|__________|__________|___________|_______|
                      |         |          |          |           |       |
Engines and tenders.  |   180   |$ 8,227.47|$ 2,904.30|$ 11,131.77|$ 61.82|
Pass., bag., and mail |         |          |          |           |       |
  cars.               |   168   |    734.93|     59.67|     794.60|   4.73|
Freight cars and      |         |          |          |           |       |
  cabooses.           | 5,175   | 17,425.57|  1,224.08|  18,649.65|   3.60|
M. of W. cars.        |   439   |  2,038.44|    549.47|   2,587.91|   5.89|
                      | Miles   |          |          |           |       |
                      | Track.  |          |          |           |       |
Track (inc. sidings). | 1,532.7 | 27,718.17| 40,912.09|  68,630.26|  44.78|
Bridges.              | 1,532.7 |  1,808.57|    200.00|   2,008.57|   1.31|
Track tools.          | 1,532.7 |    194.48|  2,573.83|   2,768.31|   1.80|
Storage tracks, inc.  |         |          |          |           |       |
  taking up.          |    37.02|  9,825.41|  1,481.59|  11,307.00| 305.44|
Shop tools.           |         |    472.20|  2,728.30|   3,200.50|       |
                      |_________|__________|__________|___________|_______|
                      |         |          |          |           |       |
  Total cost.         |         |$68,445.24|$52.633.33|$121,078.57|       |
  Total average cost  |         |          |          |           |       |
   per mile.          |         |          |          |           |$ 79.06|
______________________|_________|__________|__________|___________|_______|


  Axles condemned                                                     577
  Wheels condemned                                                    754
  Wheels burst                                                        202
  New axles used                                                    1,102
  New wheels used                                                   2,783
  Axles turned back                                                 8,316
  Wheels pressed on without turning axle                           23,952
  New brasses used                                                 10,723
  Cars narrowed (not including lever or push cars)                  5,343
  Engines narrowed                                                    180
  Average cost of new centers and crank pins, etc                 $264.46
  Average cost of cutting off hub and pressing wheels and new pins 130.67
  Average cost of pressing old tires on old centers                 29.08
  Average cost of pressing old tires on broad centers               31.83
  Average cost of labor putting on new tires                        22.94


     COMPARATIVE STATEMENT OF AVERAGE COST OF VARIOUS ITEMS OF WORK.

__________________________________________________________________________
                                  |         |         |         |         |
                                  |  M. &   |  L. &   | E.T., V.|Average. |
                                  | O. R.R. | N. R.R. |& G. R.R.|         |
                                  |_________|_________|_________|_________|
                                  |         |         |         |         |
Engines and tenders--per engine   | $325.70 | $202.58 |  $61.82 | $196.70 |
Pass., bag., and ex. cars--per car|    9.87 |[2] 5.81 |    4.73 |    6.80 |
Freight cars, per car             |    4.40 |[3] 5.81 |    3.60 |    4.60 |
M. of W. cars, per car            |   13.32 |    2.72 |    5.89 |    7.31 |
Track (inc. sidings bridges,      |         |         |         |         |
  etc.), per mile                 |   45.37 |   47.83 |   46.09 |   46.26 |
Track tools, per mile             |    2.70 |    1.31 |    1.80 |    1.94 |
Temporary side tracks, per mile   |  192.83 |         |  305.44 |  249.13 |
                                  |_________|_________|_________|_________|
   Total per mile of track, inc.  |         |         |         |         |
     sidings                      | $113.68 | $100.67 | $ 79.06 | $ 97.80 |
__________________________________|_________|_________|_________|_________|

  [Footnote 2: Expense not divided as between passenger and freight
  cars.]

  [Footnote 3: 3.5 per cent. passenger, baggage, and express cars,
  96.5 per cent. freight cars.]


NOTE--Since the preparation of this paper the general manager of the
Norfolk & Western Railroad has kindly furnished the following items of
expense for that line:

  ___________________________________________________________________
                                    |         |            |         |
                                    |   No.   |   Cost.    | Average |
                                    |         |            |  Cost.  |
                                    |_________|____________|_________|
                                    |         |            |         |
  Engines and tenders               |    95   | $37,730.00 | $397.16 |
  Cars (all kinds)                  | 3,615   |  37,994.65 |   10.51 |
  Track, miles (including sidings)  |   597.5 |            |         |
  Labor                             |         |  25,296.96 |         |
  Tools and supplies                |         |   3,531.12 |         |
  Changing M. of W. equipment       |         |     813.13 |         |
  Switches                          |         |     571.67 |         |
  Spikes                            |         |   8,508.22 |         |
                                    |         | ---------- |         |
    Total track                     |         | $38,721,10 |   64.80 |
                                    |         | ========== |         |
      Total                         |         |$114,445.75 |---------|
    Total average cost per mile     |         |            | $191.53 |
  __________________________________|_________|____________|_________|


And the superintendent of the S.F. & W. R.R. has also furnished the
expenses for that road:

  ___________________________________________________________________
                                                |          |         |
                                                |   No.    | Average |
                                                |          |  Cost.  |
                                                |__________|_________|
                                                |          |         |
  Engines and tenders                           |    75    |  $76.31 |
  Cars (passenger)                              |    95    |    4.67 |
  Cars (freight)                                | 1,133    |    3.88 |
  Track, including sidings                      |   601.76 |   44.49 |
  ______________________________________________|__________|_________|

Nothing was said about shop or other tools, storage tracks, or
changing of maintenance of way equipment.


            COMPARATIVE STATEMENT OF AVERAGE COST OF
               LABOR OF VARIOUS ITEMS OF WORK.
  _________________________________________________________________
                            |   M. &  |   L. & | E.T., V. |        |
                            | O. R.R. | N. R.R.| & G. R.R.| Average|
                            |_________|________|__________|________|
                            |         |        |          |        |
  Engines and tenders.      | $170.88}|        | {$45.71  | $108.29|
  Pass., bag., and ex cars  |    7.97}|   Not  | {  4.38  |    6.17|
  Freight cars              |    3.89}| divided| {  3.36  |    3.62|
  M. of W. cars             |    9.98}|        | {  4.64  |    7.31|
  Miles track (including    |         |        |          |        |
   sidings, bridges, etc.)  |   32.57 |  $34.31|   19.26  |   28.71|
  Track tools, per mile     |     .30 |   Not  |     .13  |     .21|
  Temporary tracks          |  162.03 | divided|  265.40  |  213.71|
                            |_________|________|__________|________|
                            |         |   Not  |          |        |
  Total per mile of track   |  $70.38 | divided|  $44.72  |  $57.55|
  __________________________|_________|________|__________|________|


            COMPARATIVE STATEMENT OF AVERAGE COST OF
               MATERIAL OF VARIOUS ITEMS OF WORK.
  _________________________________________________________________
                            |   M. &  |   L. & | E.T., V. |        |
                            | O. R.R. | N. R.R.| & G. R.R.| Average|
                            |_________|________|__________|________|
                            |         |        |          |        |
  Engines and tenders.      | $154.82}|        | { $16.11 |  $85.46|
  Pass., bag., and ex cars  |    1.90}|   Not  | {    .35 |    1.12|
  Freight cars              |     .51}| divided| {    .24 |     .37|
  M. of W. cars             |    3.34}|        | {   1.25 |    2.30|
  Miles track (including    |         |        |          |        |
   sidings, bridges, etc.)  |   12.80 |  $13.02|    26.88 |   17.55|
  Track tools, per mile     |    2.40 |   Not  |     1.67 |    2.03|
  Temporary tracks          |  162.03 | divided|    40.04 |  101.03|
  __________________________|_________|________|__________|________|
                            |         |   Not  |          |        |
  Total per mile of track   |  $43.30 | divided|   $34.34 |  $38.82|
  __________________________|_________|________|__________|________|


             SUMMARY OF STATEMENTS OF L.& N. AND E.T.,
                         V.& G. RAILWAYS.

  The mileage changed of the L&N. and E.T., V.& G.
    systems combined aggregates                         3,622 miles.
  The total cost of these two roads.                     $331,492.59
  Or an average per mile of                                    91.52
  Total miles changed was about                        14,500 miles.
  Which would give total cost, at same rate.              $1,327,040


We should really add to this a large sum for the great number of new
locomotives which were purchased to replace old ones, that could not
be changed, except at large cost, and which, when done, would have
been light and undesirable.

Upon the basis of the work done upon the L. & N. and E.T., V. & G.
systems, which, combined, cover about one-fourth the mileage changed,
we have made the following estimates, which will, perhaps, convey a
better idea of the extent of the work than can be obtained in any
other way:

  Miles of track changed, about                               14,500
  Locomotives changed, about                                   1,800
  Cars (pass, and freight) changed, about                     45,000
  New axles used, about                                        9,000
  New wheels used, about                                      20,000
  Axles turned back, about                                    75,000
  Wheels pressed on without turning axles, about             220,000
  New brasses used, about                                     90,000
  Kegs of spikes used, about                                  50,000
  Cost of material used, about                              $600,000
  Cost of labor, about                                       730,000
  Total cost of work, about                                1,330,000
  Amount expended on equipment, about                        650,000
  Amount expended on track, about                            680,000
  Amount expended on track on day of change in labor, about  140,000

The work was done economically, and so quietly that the public hardly
realized it was in progress. To the casual observer it was an every
day transaction. It was, however, a work of great magnitude, requiring
much thought and mechanical ability.

That it was ably handled is evidenced by the uniform success attained,
the prompt changing at the agreed time, and the trifling inconvenience
to the public.--_Jour. Assn. Engineering Societies._

       *       *       *       *       *




TORPEDO BOATS FOR SPAIN.


In our present issue, on page 9948, we give illustrations of two
torpedo boats, the Azor and Halcon, which have lately been constructed
by Messrs Yarrow & Co., of Poplar, for the Spanish government. They
are 135 ft. in length by 14 ft. beam, being of the same dimensions as
No. 80 torpedo boat, lately completed by the above firm for the
Admiralty, which is the largest and fastest torpedo-boat in the
British navy.

[Illustration: TORPEDO BOATS FOR THE SPANISH GOVERNMENT.]

The general arrangement of these torpedo boats is sufficiently clear
from the illustrations to need but little description. Suffice it to
say that the engines are of the triple compound type, capable of
indicating 1,550 horse power, steam being supplied by one large
locomotive boiler, which our readers are already aware is in
accordance with the usual practice of the makers, as, by using a
single boiler, great simplification of the machinery takes place, and
considerably less room is occupied than if two boilers were adopted.
It is worthy of record that although in some torpedo boats, and indeed
in a great number of them, trouble has been found with the locomotive
type of boiler, still we have no hesitation in saying that this is due
either to defective design or bad workmanship, and that, if properly
designed and constructed, such difficulty does not occur. And it is a
fact that Messrs. Yarrow & Co. have already constructed a great number
of locomotive boilers of the exceptional size adopted in these two
Spanish boats, and they have turned out in every respect, after actual
service, perfectly satisfactory.

The forward part of the boat is provided with two torpedo-ejecting
tubes, as usual, and near the stern, on deck, it is proposed to place
turntables, with two torpedo guns for firing over the sides, as
already adopted by several governments. The trials of the Azor took
place about two months since, giving a speed during a run of two hours
and three quarters, carrying a load of 17 tons, of 24 knots (over 27½
miles) per hour. Since her trial she has steamed out to Spain, having
encountered, during a portion of the voyage very bad weather, when her
sea going qualities were found to be admirable.

The Halcon, whose official trials took place lately, obtained a speed
of 23.5 knots, carrying a load of 17 tons. It may be remarked that a
speed of 24 knots, in a boat only 135 ft in length, under the Spanish
conditions of trial, is by far the best result that has ever been
obtained in a vessel of these dimensions There is, however, no doubt
that had the length of the boat been greater, a still higher speed
would have been obtained But it was desired by the authorities to keep
within the smallest possible dimensions, so as to expose as little
area as practicable to the fire of the enemy, it being clearly evident
that this is a consideration of the first importance in an unprotected
war vessel.

In conclusion, we would add that the hulls of these two Spanish boats
are of much greater strength of construction than is usually adopted
in torpedo boats, it having been found that for the sake of obtaining
exceptional speeds, strength sufficient for actual service has often
been injudiciously sacrificed And, judging from the numerous accidents
which took place at the recent trials off Portland, we have no doubt
that in the future naval authorities will be quite ready and willing
to sacrifice a little speed so as to obtain vessels which are more
trustworthy. The necessity for this, we feel convinced, will be
conclusively shown if ever torpedo boats are engaged in actual
warfare, and this not only as regards strength of hull, but also as
regards the machinery, which at present is only capable of being
handled successfully by men of exceptional training, who in times of
war would not be readily procured--_The Engineer._

       *       *       *       *       *




THE SPANISH CRUISER REINA REGENTE


In our SUPPLEMENT, No. 620 we gave an illustration of this ship, with
some particulars. The interest expressed in naval circles for further
information induces us to give still further engravings of this
remarkable vessel, with additional information, for which we are
indebted to the _Engineer_.

[Illustration: THE NEW SPANISH WAR SHIP REINA REGENTE.]

We gave recently a short account of two of the trials of this vessel,
and we are, by the courtesy of the builders--Messrs. Thomson, of
Clydebank--enabled to lay further particulars before our readers this
week. We give herewith engravings of the vessel, which will illustrate
her salient points. The principal dimensions are as follows.

Length on water line, 317 ft., breadth, 50 ft. 7 in., depth moulded,
32 ft. 6 in., normal displacement, 4,800 tons, deep load displacement,
5,600 tons. We have before informed our readers that this vessel was
designed by Messrs. Thomson, in competition with several other
shipbuilding firms of this and other countries, in reply to an
invitation of the Spanish government for a cruiser of the first class.
The design submitted by the builders of the Reina Regente was
accepted, and the vessel was contracted to be built in June of last
year. The principal conditions of the contract were as follows.

The ship to steam at a speed of 20½ knots for four runs on the mile
and for two hours continuously afterward. She was further to be
capable of steaming for six hours continuously at a speed of 18½
knots, without any artificial means of producing draught. She was also
to be capable of steaming a distance of at least 5,700 knots for 500
tons of coal, at some speed over 10 knots, to be chosen by the
builders. Over the length of her machinery and magazine spaces she was
to have a sloping deck extending to 6 ft. below the water line at the
side, and formed of plates 4¾ in. thick. This deck was to extend to
about 1 ft. above the water line, and the flat part to be 3-1/8 in.
thick. Beyond the machinery and magazine spaces, the deck was to be
gradually reduced to 3 in. thick at the ends. This deck is intended to
protect the vitals of the ship, such as boilers, engines, powder
magazines, steering gear, etc., from the effects of shot and shell,
but the floating and stability maintaining power of the ship was to be
dependent upon a similar structure raised above this protective deck
to a height of about 5 ft. above the water.

This structure is covered by a water tight deck known as the main deck
of the ship, on which the cabins and living spaces are arranged. The
space between the main and protective deck is divided, as may be seen
by reference to the protective deck plan, into many strong, water
tight spaces, most of which are not more than about 500 cubic feet
capacity. The spaces next to the ship's side are principally coal
bunkers, and may, therefore, exclude largely any water that should
enter. The first line of defense is formed inside these coal bunkers
by a complete girdle of coffer dams, which can be worked from the main
deck. These it is intended to fill with water and cellulose material,
and as they are also minutely subdivided, the effects of damage by
shot and consequent flooding may be localized to a considerable
extent. The guns of the ship are to consist of four 20 centimeter
Hontorio breech loading guns on Vavasseur carriages, six 12 centimeter
guns, eight 6 pounder rapid firing, and eight or ten small guns for
boats and mitrailleuse purposes, four of which are in the crow's nests
at the top of the two masts of the ship. We may remark in passing that
the builders saw their way at an early period of the construction to
suggest an addition to the weight of the large sized guns, and there
will actually be on the ship four 24 centimeter guns, instead of four
20 centimeter. The vessel was to carry five torpedo tubes, two forward
in the bow, one in each broadside, and one aft. All these tubes to be
fixed. To fulfill the speed condition, four boilers were necessary and
two sets of triple expansion engines, capable of developing in all
12,000 horse power.

[Illustration: PROTECTIVE DECK PLAN.]

Now that the vessel has been completely tried, the promises by the
builders may be compared with the results determined by the commission
of Spanish officers appointed by the government of Spain to say
whether the vessel fulfilled in all respects the conditions laid down
in the contract. The mean speed attained for the two hours' run was
20.6 knots, as compared with 20.5 guaranteed, but this speed was
obtained with 11,500 horse power instead of the 12,000 which the
machinery is capable of developing. The officers of the Spanish
commission were anxious not to have the vessel's machinery pressed
beyond what was necessary to fulfill the speed conditions of the
contract; but they saw enough to warrant them in expressing their
belief that the vessel can easily do twenty-one knots when required,
and she actually did this for some time during the trial.

During the natural draught trial the vessel obtained a mean speed of
18.68 knots, on an average of 94¾ revolutions--the forced draught
having been done on an average of 105½ revolutions. The consumption
trial, which lasted twelve hours, was made to determine the radius of
action, when the ship showed that at a speed of 11.6 knots she could
steam a distance of 5,900 knots. Further trials took place to test the
evolutionary powers of the vessel, though these trials were not
specified in the contract.

The vessel, as may be seen from the engravings, is fitted with a
rudder of a new type, known as Thomson & Biles' rudder, with which it
is claimed that all the advantage of a balanced rudder is obtained,
while the ship loses the length due to the adoption of such a rudder.
It is formed in the shape of the hull of the vessel, and as the
partial balance of the lower foreside gradually reduces the strains,
the rudder head may be made of very great service. As a matter of
fact, this rudder is 230 ft. in area, and is probably the largest
rudder fitted to a warship. The efficiency of it was shown in the
turning trials, by its being able to bring the vessel round, when
going at about nineteen knots, in half a circle in one minute
twenty-three seconds, and a complete circle in two minutes fifty-eight
seconds, the diameter of the circle being 350 yards. This result, we
believe, is unrivaled, and makes this vessel equal in turning
capabilities to many recent warships not much more than half her
length.

       *       *       *       *       *




FILM NEGATIVES.[1]

  [Footnote 1: A communication to the Birmingham Photographic
  Society.]


Having had a certain measure of success with Eastman stripping films,
I have been requested by your council to give a paper this evening
dealing with the subject, and particularly with the method of working
which my experience has found most successful. In according to their
request, I feel I have imposed upon myself a somewhat difficult task.

There is, undoubtedly, a strong prejudice in the minds of most
photographers, both amateur and professional, against a negative in
which paper is used as a permanent support, on account of the
inseparable "grain" and lack of brilliancy in the resulting prints;
and the idea of the paper being used only as a temporary support does
not seem to convey to their mind a correct impression of the true
position of the matter.

It may be as well before entering into the technical details of the
manipulation to consider briefly the advantages to be derived--which
will be better appreciated after an actual trial.

My experience (which is at present limited) is that they are far
superior to glass for all purposes except portraiture of the human
form or instantaneous pictures where extreme rapidity is necessary,
but for all ordinary cases of rapid exposure they are sufficiently
quick. The first advantage, which I soon discovered, is their entire
freedom from halation. This, with glass plates, is inseparable, and
even when much labor has been bestowed on backing them, the halation
is painfully apparent.

These films never frill, being made of emulsion which has been made
insoluble. Compare the respective weights of the two substances--one
plate weighing more than a dozen films of the same size.

Again, on comparing a stripping film negative with one on glass of the
same exposure and subject, it will be found there is a greater
sharpness or clearness in the detail, owing, I am of opinion, to the
paper absorbing the light immediately it has penetrated the emulsion,
the result being a brilliant negative. Landscapes on stripped films
can be retouched or printed from on either side, and the advantage in
this respect for carbon or mechanical printing is enormous. Now,
imagine the tourist working with glass, and compare him to another
working with films. The one works in harness, tugging, probably, a
half hundredweight of glass with him from place to place, paying extra
carriage, extra tips, and in a continual state of anxiety as to
possible breakage, difficulty of packing, and having to be continually
on the lookout for a dark place to change the plates, and, perhaps, on
his return finds numbers of his plates damaged owing to friction on
the surface; while the disciple of _films_, lightly burdened with only
camera and slide, and his (say two hundred) films in his pockets, for
they lie so compact together. Then the advantages to the tourists
abroad, their name is "legion," not the least being the ease of
guarding your exposed pictures from the custom house officials, who
almost always seek to make matters disagreeable in this respect, and
lastly, though not least, the ease with which the negatives can be
stowed away in envelopes or albums, etc., when reference to them is
easy in the extreme.

Now, having come (rightly, I think, you will admit) to the conclusion
that films have these advantages, you naturally ask, What are their
disadvantages? Remembering, then, that I am only advocating stripping
films, I consider they have but two disadvantages: First, they entail
some additional outlay in the way of apparatus, etc. Second, they are
a little more trouble to finish than the glass negatives, which sink
into insignificance when the manifold advantages are considered.

In order to deal effectively with the second objection I mentioned,
viz., the extra trouble and perseverance, I propose, with your
permission, to carry a negative through the different stages from
exposure to completion, and in so doing I shall endeavor to make the
process clear to you, and hope to enlist your attention.

The developer I use is slightly different to that of the Eastman
company, and is as follows:

                           A.
    Sulphite of soda.           4 ounces.

To be dissolved in 8 ounces of hot distilled water, then rendered
slightly acid with citric acid, then add--

    Pyrogallic acid.            1 ounce.
    Water to make up to 10 ounces.

                           B.
    Pure carbonate of soda.     1 ounce.
    Water to make up in all to 10 ounces.

                           C.
    Pure carbonate of potash.   1 ounce.
    Water to make up to 10 ounces.

                           D.
    Bromide of potassium.       1 ounce.
    Water to make up to 10 ounces.

I have here two half-plate films exposed at 8:30 A.M. to-day, one with
five and one with six seconds' exposure, subject chiefly middle
distance. I take 90 minims A, 10 minims D, and 90 minims B, and make
up to 2 ounces water. I do not soak the films in water. There is no
need for it. In fact, it is prejudicial to do so. I place the films
face uppermost in the dish, and pour on the developer on the center of
the films. You will observe they lie perfectly flat, and are free from
air bubbles. Rock the dish continually during development, and when
the high lights are out add from 10 to 90 minims C, and finish
development and fix. The negatives being complete, I ask you to
observe that both are of equal quality, proving the latitude of
exposure permissible.

I now coat a piece of glass half an inch larger all round than the
negative with India rubber solution (see Eastman formula), and
squeegee the negative face downward upon the rubber, interposing a
sheet of blotting paper and oilskin between the negative and squeegee
to prevent injury to the exposed rubber surface, and then place the
negative under pressure with blotting paper interposed until
moderately dry only.

I then pour hot water upon it, and, gently rocking the dish, you see
the paper floats from the film without the necessity for pulling it
with a pin, leaving the film negative on the glass. Now, the
instructions say remove the remaining soluble gelatine with camel's
hair brush, but, unless it requires intensifying, which no properly
developed negative should require, you need not do so, but simply pour
on the gelatine solution (see Eastman formula), well covering the
edges of the film, and put on a level shelf to dry.

I will now take up a negative in this state on the glass, but dry, and
carefully cut round the edges of the film, and you see I can readily
pull off the film with its gelatine support. Having now passed through
the whole of the process, it behooves us to consider for a few minutes
the causes of failure in the hands of beginners and their remedies: 1.
The rubber will not flow over glass? Solution too thick, glass greasy.
2. Rubber peels off on drying? Dirty glass. 3. Negative not dense
enough? Use more bromide and longer development. 4. Gelatine cracks on
being pulled off? Add more glycerine. 5. Gelatine not thick enough?
Gelatine varnish too thin, not strong enough. 6. Does not dry
sufficiently hard? Too much glycerine.--_E.H. Jaques, Reported in Br.
Jour. of Photography._

       *       *       *       *       *




HOW DIFFERENT TONES IN GELATINO-CHLORIDE PRINTS MAY BE VARIED BY
DEVELOPERS.


The following formulæ are for use with gelatino-chloride paper or
plates. The quantities are in each case calculated for one ounce,
three parts of each of the following solutions being employed and
added to one part of solution of protosulphate of iron. Strength, 140
grains to the ounce.

            _Slaty Blue._

  1.--One part of the above solution
  to three parts of a solution of citrate of ammonia.

            _Greenish Brown._
     2.--Citric acid.               180 grains
         Carbonate of ammonia.       50   "

     3.--Citrate of ammonia.        250 grains.
         Chloride of sodium.          2   "

     4.--Citrate of ammonia.        250 grains.
         Chloride of sodium.          4   "

            _Sepia Brown._
     5.--Citrate of ammonia.        250 grains.
         Chloride of sodium.          8   "

            _Clear Red Brown._
     6.--Citric acid.               120 grains.
         Carbonate of magnesia.      76   "

            _Warm Gray Brown._
     7.--Citric acid.               120 grains.
         Carbonate of soda.         205   "

            _Deep Red Brown._
     8.--Citric acid.               120 grains.
         Carbonate of potash.       117   "

            _Green Blue._
     9.--Citric acid.                90 grains.
         Carbonate of soda.         154   "
         Citrate of potash.          24   "
         Oxalate of potash.           6   "

             _Sepia Red._
    10.--Citric acid.                80 grains.
         Carbonate of soda.         135   "
         Citrate of potash.          12   "
         Oxalate of potash.           3   "

    11.--Citric acid.               108 grains.
         Carbonate of magnesia.      68   "
         Carbonate of potash.        12   "
         Oxalate of potash.           3   "

             _Sepia Yellow._
    12.--Citric acid.                40 grains.
         Carbonate of magnesia.      25   "
         Citrate of ammonia.        166   "

    13.--Citric acid.               120 grains.
         Carbonate of magnesia.      72   "
         Carbonate of ammonia.       72   "
         Chloride of sodium.          8   "

             _Blue Black._
    14.--Citric acid.               120 grains.
         Carbonate of ammonia.       70   "
         Carbonate of magnesia.      15   "

    15.--Citric acid.               120 grains.
         Carbonate of magnesia.      38   "
         Carbonate of ammonia.       44   "

    16.--Citric acid.                90 grains.
         Carbonate of magnesia.      57   "
         Citrate of potash.          54   "
         Oxlate of potash.           18   "

    17.--Citric acid.                72 grains.
         Carbonate of magnesia.      45   "
         Citrate of potash.          54   "
         Oxalate of potash.          18   "

    18.--Citric acid.                60 grains.
         Carbonate of magnesia.      38   "
         Citrate of potash.          68   "
         Oxalate of potash.          22   "

        _A more Intense Blue Black._
    19.--Citric acid.                30 grains.
         Carbonate of magnesia.      18   "
         Citrate of potash.         100   "
         Oxalate of potash.          33   "

           _A Clearer Blue._
    20.--Citrate of potash.         136 grains.
         Oxalate of potash.          44   "

In the photographic exhibition at Florence, the firm of Corvan[1]
places on view a frame containing twenty proofs produced by the
foregoing twenty formulæ, in such a way that the observer can compare
the value of each tone and select that which pleases him best.--_Le
Moniteur de la Photographie, translated by British Jour. of Photo._

  [Footnote 1: Does this mean Mr. A. Cowan?--_Translator._]

       *       *       *       *       *




NOTE ON THE CONSTRUCTION OF A DISTILLERY CHIMNEY.


At a recent meeting of the Industrial Society of Amiens, Mr. Schmidt,
engineer of the Steam Users' Association, read a paper in which he
described the process employed in the construction of a large chimney
of peculiar character for the Rocourt distillery, at St. Quentin.

[Illustration: FIG. 1--ELEVATION.]

This chimney, which is cylindrical in form, is 140 feet in height, and
has an internal diameter of 8½ feet from base to summit. The coal
consumed for the nine generators varies between 860 and 1,200 pounds
per hour and per 10 square feet of section.

The ground that was to support this chimney consisted of very
aquiferous, cracked beds of marl, disintegrated by infiltrations of
water from the distillery, and alternating with strata of clay. It
became necessary, therefore, to build as light a chimney as possible.
The problem was solved as follows, by Mr. Guendt, who was then
superintendent of the Rocourt establishment.

Upon a wide concrete foundation a pedestal was built, in which were
united the various smoke conduits, and upon this pedestal were erected
four lattice girders, C, connected with each other by St. Andrew's
crosses. The internal surface of these girders is vertical and the
external is inclined. Within the framework there was built a five-inch
thick masonry wall of bricks, made especially for the purpose. The
masonry was then strengthened and its contact with the girders assured
by numerous hoops, especially at the lower part; some of them
internal, others external, to the surface of the girders, and others
of angle irons, all in four parts.

[Illustration: FIG. 2--HORIZONTAL SECTION.]

The anchors rest upon a cast iron foundation plate connected, through
strong bolts embedded in the pedestal, with a second plate resting
upon the concrete.

As the metallic framework was calculated for resisting the wind, the
brick lining does not rest against it permanently above. The weight of
the chimney is 1,112,200 pounds, and the foundation is about 515
square feet in area; and, consequently, the pressure upon the ground
is about 900 pounds to the square inch. The cost was $3,840.

[Illustration: FIG. 3--VERTICAL SECTION OF THE CHIMNEY.]

The chimney was built six years ago, and has withstood the most
violent hurricanes.

The mounting of the iron framework was effected by means of a motor
and two men, and took a month. The brick lining was built up in eight
days by a mason and his assistant.

A chimney of the same size, all of brick, erected on the same
foundation, would have weighed 2,459,600 pounds (say a load of 3,070
pounds to the square inch), and would have cost about $2,860.

The chimney of the Rocourt distillery is, therefore, lighter by half,
and cost about a third more, than one of brick; but, at the present
price of metal, the difference would be slight.--_Annales
Industrielles._

       *       *       *       *       *




THE PRODUCTION OF OXYGEN BY BRIN'S PROCESS.


Considerable interest has been aroused lately in scientific and
industrial circles by a report that separation of the oxygen and
nitrogen of the air was being effected on a large scale in London by a
process which promises to render the gases available for general
application in the arts. The cheap manufacture of the compounds of
nitrogen from the gas itself is still a dream of chemical enthusiasts;
and though the pure gas is now available, the methods of making its
compounds have yet to be devised. But the industrial processes which
already depend directly or indirectly on the chemical union of bodies
with atmospheric oxygen are innumerable.

In all these processes the action of the gas is impeded by the bulky
presence of its fellow constituent of air, nitrogen. We may say, for
instance, in homely phrase, that whenever a fire burns there are four
volumes of nitrogen tending to extinguish it for every volume of
oxygen supporting its combustion, and to the same degree the nitrogen
interferes with all other processes of atmospheric oxidation, of which
most metallurgical operations may be given as instances. If, then, it
has become possible to remove this diluent gas simply and cheaply in
order to give the oxygen free play in its various applications, we are
doubtless on the eve of a revolution among some of the most extensive
and familiar of the world's industries.

A series of chemical reactions has long been known by means of which
oxygen could be separated out of air in the laboratory, and at various
times processes based on these reactions have been patented for the
production of oxygen on a large scale. Until recently, however, none
of these methods gave sufficiently satisfactory results. The simplest
and perhaps the best of them was based on the fact first noticed by
Boussingault, that when baryta (BaO) is heated to low redness in a
current of air, it takes up oxygen and becomes barium dioxide
(BaO_{2}), and that this dioxide at a higher temperature is
reconverted into free oxygen and baryta, the latter being ready for
use again. For many years it was assumed, however, by chemists that
this ideally simple reaction was inapplicable on a commercial scale,
owing to the gradual loss of power to absorb oxygen which was always
found to take place in the baryta after a certain number of
operations. About eight years ago Messrs. A. & L. Brin, who had
studied chemistry under Boussingault, undertook experiments with the
view of determining why the baryta lost its power of absorbing oxygen.

They found that it was owing to molecular and physical changes caused
in it by impurities in the air used and by the high temperature
employed for decomposing the dioxide. They discovered that by heating
the dioxide in a partial vacuum the temperature necessary to drive off
its oxygen was much reduced. They also found that by supplying the air
to the baryta under a moderate pressure, its absorption of oxygen was
greatly assisted. Under these conditions, and by carefully purifying
the air before use, they found that it became possible to use the
baryta an indefinite number of times. Thus the process became
practically, as it was theoretically, continuous.

After securing patent protection for their process, Messrs. Brin
erected a small producer in Paris, and successfully worked it for
nearly three years without finding a renewal of the original charge of
baryta once necessary. This producer was exhibited at the Inventions
Exhibition in London, in 1885. Subsequently an English company was
formed, and in the autumn of last year Brin's Oxygen Company began
operations in Horseferry Road, Westminster, where a large and complete
demonstration plant was erected, and the work commenced of developing
the production and application of oxygen in the industrial world.

[Illustration: APPARATUS FOR MAKING OXYGEN.]

We give herewith details of the plant now working at Westminster. It
is exceedingly simple. On the left of the side elevation and plan are
shown the retorts, on the right is an arrangement of pumps for
alternately supplying air under pressure and exhausting the oxygen
from the retorts. As is shown in the plan, two sets of apparatus are
worked side by side at Westminster, the seventy-two retorts shown in
the drawings being divided into two systems of thirty-six. Each system
is fed by the two pumps on the corresponding side of the boiler. Each
set of retorts consists of six rows of six retorts each, one row above
the other. They are heated by a small Wilson's producer, so that the
attendant can easily regulate the supply of heat and obtain complete
control over the temperature of the retorts. The retorts, A, are made
of wrought iron and are about 10 ft long and 8 in. diameter.
Experience, however, goes to prove that there is a limit to the
diameter of the retorts beyond which the results become less
satisfactory. This limit is probably somewhat under 8 in. Each retort
is closely packed with baryta in lumps about the size of a walnut. The
baryta is a heavy grayish porous substance prepared by carefully
igniting the nitrate of barium; and of this each retort having the
above dimensions holds about 125 lb. The retorts so charged are closed
at each end by a gun metal lid riveted on so as to be air tight. From
the center of each lid a bent gun metal pipe, B, connects each retort
with the next of its series, so that air introduced into the end
retort of any row may pass through the whole series of six retorts.
Suppose now that the operations are to commence.

The retorts are first heated to a temperature of about 600° C. or
faint redness, then the air pumps, C C, are started. Air is drawn by
them through the purifier, D, where it is freed from carbon dioxide
and moisture by the layers of quicklime and caustic soda with which
the purifier is charged. The air is then forced along the pipe, E,
into the small air vessel, F, which acts as a sort of cushion to
prevent the baryta in the retorts being disturbed by the pulsation of
the pumps. From this vessel the air passes by the pipe, G, and is
distributed in the retorts as rapidly as possible at such a pressure
that the nitrogen which passes out unabsorbed at the outlet registers
about 15 lb. to the square inch. With the baryta so disposed in the
retorts as to present as large a superficies as possible to the action
of the air, it is found that in 1½ to 2 hours--during which time about
12,000 cub. ft of air have been passed through the retorts--the gas at
the outlet fails to extinguish a glowing chip, indicating that oxygen
is no longer being absorbed. The pumping now ceases, and the
temperature of the retorts is raised to about 800° C. The workman is
able to judge the temperature with sufficient accuracy by means of the
small inspection holes, H, fitted with panes of mica, through which
the color of the heat in the furnace can be distinguished. The pumps
are now reversed and the process of exhaustion begins. At Westminster
the pressure in the retorts is reduced to about 1½ in. of mercury. In
this partial vacuum the oxygen is given off rapidly, and if forced by
the pumps through another pipe and away into an ordinary gas holder,
where it is stored for use. With powerful pumps such as are used in
the plant under notice the whole of the oxygen can be drawn off in an
hour, and from one charge a yield of about 2,000 cub. ft. is obtained.
With a less perfect vacuum the time is longer--even as much as four
hours. The whole operation of charging and exhausting the retorts can
be completed in from three to four hours. As soon as the evolution of
oxygen is finished, the doors, K, and ventilators, L, may be opened
and the retorts cooled for recharging.

The cost of producing oxygen at Westminster, under specially expensive
conditions, is high--about 12s. per 1,000 cub. ft. When we consider,
however, that the cost should only embrace attendance, fuel, wear and
tear, and a little lime and soda for the purifiers, that the
consumption of fuel is small, the wear and tear light, and that the
raw material--air--is obtained for nothing, it ought to be possible to
produce the gas for a third or fourth of this amount in most of our
great manufacturing centers, where the price of fuel is but a third of
that demanded in London, and where provision could be made for
economizing the waste heat, which is entirely lost in the Westminster
installation. Moreover, in estimating this cost all the charges are
thrown on the oxygen; were there any means of utilizing the 4,000 cub.
ft. of nitrogen at present blown away as waste for every thousand
cubic feet of oxygen produced, the nitrogen would of course bear its
share of the cost.

The question of the application of the oxygen is one which must be
determined in its manifold bearings mainly by the experiments of
chemists and scientific men engaged in industrial work. Having
ascertained the method by which and the limit of cost within which it
is possible to use oxygen in their work, it can be seen whether by
Brin's process the gas can be obtained within that limit.

Mr. S.R. Ogden, the manager of the corporation gasworks at Blackburn,
has already made interesting experiments on the application of oxygen
in the manufacture of illuminating gas. In order to purify coal gas
from compounds of sulphur, it is passed through purifiers charged with
layers of oxide of iron. When the oxide of iron has absorbed as much
sulphur as it can combine with, it is described as "foul." It is then
discharged and spread out in the open air, when, under the influence
of the atmospheric oxygen, it is rapidly decomposed, the sulphur is
separated out in the free state, and oxide of iron is reformed ready
for use again in the purifiers. This process is called revivification,
and it is repeated until the accumulation of sulphur in the oxide is
so great (45 to 55 per cent.) that it can be profitably sold to the
vitriol maker. Hawkins discovered that by introducing about 3 per
cent. of air into the gas before passing it through the purifiers, the
oxygen of the air introduced set free the sulphur from the iron as
fast as it was absorbed. Thus the process of revivification could be
carried on in the purifiers themselves simultaneously with the
absorption of the sulphur impurities in the gas.

A great saving of labor was thus effected, and also an economy in the
use of the iron oxide, which in this way could be left in the
purifiers until charged with 75 per cent. of sulphur. Unfortunately it
was found that this introduction of air for the sake of its oxygen
meant also the introduction of much useless nitrogen, which materially
reduced the illuminating power of the gas. To restore this
illuminating power the gas had to be recarbureted, and this again
meant cost in labor and material. Now, Mr. Ogden has found by a series
of conclusive experiments made during a period of seventy-eight days
upon a quantity of about 4,000,000 cub. ft. of gas, that by
introducing 1 per cent. of oxygen into the gas instead of 3 per cent.
of air, not only is the revivification _in situ_ effected more
satisfactorily than with air, but at the same time the illuminating
power of the gas, so far from being decreased, is actually increased
by one candle unit.

[Illustration: THE PRODUCTION OF OXYGEN BY BRIN'S PROCESS.]

So satisfied is he with his results that he has recommended the
corporation to erect a plant for the production of oxygen at the
Blackburn gas works, by which he estimates that the saving to the town
on the year's make of gas will be something like £2,500. The practical
observations of Mr. Ogden are being followed up by a series of
exhaustive experiments by Mr. Valon, A.M. Inst. C.E., also a gas
engineer. The make of an entire works at Westgate is being treated by
him with oxygen. Mr. Valon has not yet published his report, as the
experiments are not quite complete; but we understand that his results
are even more satisfactory than those obtained at Blackburn.

In conclusion we may indicate a few other of the numerous possible
applications of cheap oxygen which might be realized in the near
future. The greatest illuminating effect from a given bulk of gas is
obtained by mixing it with the requisite proportion of oxygen, and
holding in the flame of the burning mixture a piece of some solid
infusible and non-volatile substance, such as lime. This becomes
heated to whiteness, and emits an intense light know as the Drummond
light, used already for special purposes of illumination. By supplying
oxygen in pipes laid by the side of the ordinary gas mains, it would
be possible to fix small Drummond lights in place of the gas burners
now used in houses; this would greatly reduce the consumption of gas
and increase the light obtained, or even render possible the
employment of cheap non-illuminating combustible gases other than coal
gas for the purpose.

Two obstacles at present lie in the way of this consummation--the cost
of the oxygen and the want of a convenient and completely refractory
material to take the place of the lime. Messrs. Brin believe they have
overcome the first obstacle, and are addressing themselves, we
believe, to the removal of the second. Again, the intense heat which
the combustion of carbon in cheap oxygen will place at the disposal of
the metallurgist cannot fail to play an important part in his
operations. There are many processes, too, of metal refining which
ought to be facilitated by the use of the gas. Then the production of
pure metallic oxides for the manufacture of paints, the bleaching of
oils and fats, the reduction of refractory ores of the precious metals
on a large scale, the conversion of iron into steel, and numberless
other processes familiar to the specialists whose walk is in the
byways of applied chemistry, should all profit by the employment of
this energetic agent. Doubtless, too, the investigation into methods
of producing the compounds of nitrogen so indispensable as plant
foods, and for which we are now dependent on the supplies of the
mineral world, may be stimulated by the fact that there is available
by Brin's process a cheap and inexhaustible supply of pure
nitrogen.--_Industries._

       *       *       *       *       *




FRENCH DISINFECTING APPARATUS.


[Illustration: IMPROVED DISINFECTING APPARATUS.]

We represent herewith a sanitary train that was very successfully used
during the prevalence of an epidemic of _sudor Anglicus_ in Poitou
this year. It consisted of a movable stove and a boiler. In reality,
to save time, such agricultural locomotives as could be found were
utilized; but hereafter, apparatus like those shown in the engraving,
and which are specially constructed to accompany the stoves, will be
employed. We shall quote from a communication made by Prof. Brouardel
to the Academy of Medicine on this subject, at its session of
September 13:

In the country we can never think of disinfecting houses with
sulphurous acid, as the peasants often have but a single room, in
which the beds of the entire family are congregated. Every one knows
that the agglomerations that compose the same department are often
distant from each other and the chief town by from two to three miles
or more. This is usually the case in the departments of Vienne, Haute
Vienne, Indre, etc. To find a disinfecting place in the chief town of
the department is still difficult, and to find one in each of the
hamlets is absolutely impossible. Families in which there are invalids
are obliged to carry clothing and bedding to the chief town to be
disinfected, and to go after them after the expiration of twenty-four
hours. This is not an easy thing to do.

It is easy to understand what difficulties must be met with in many
cases, and so one has to be content to prescribe merely washing, and
bleaching with lime--something that is simple and everywhere accepted,
but insufficient. So, then, disinfection with sulphurous acid, which
is easy in large cities, as was taught by the cholera epidemics of
last year, is often difficult in the country. The objection has always
be made to it, too, that it is of doubtful efficacy. It is not for us
to examine this question here, but there is no doubt that damp steam
alone, under pressure, effects a perfect disinfection, and that if
this mode of disinfection could be applied in the rural districts (as
it can be easily done in cities), the public health would be better
protected in case of an epidemic.

In cities one or more stationary steam stoves can always be arranged;
but in the country movable ones are necessary. From instructions given
by Prof. Brouardel, Messrs. Geneste & Herscher have solved the problem
of constructing such stoves in a few days, and four have been put at
the disposal of the mission.

Dr. Thoinot, who directed this mission, in order to make an experiment
with these apparatus, selected two points in which cases of _sudor_
were still numerous, and in which the conditions were entirely
different, and permitted of studying the working of the service and
apparatus under various phases. One of these points was Dorat, chief
town of Haute Vienne, a locality with a crowded population and
presenting every desirable resource; and the other was the commune of
Mauvieres, in Indre, where the population was scattered through
several hamlets.

The first stove was operated at Dorat, on the 29th of June, and the
second at Mauvieres, on the 1st of July. A gendarme accompanied the
stove in all its movements and remained with it during the
disinfecting experiments. The Dorat stove was operated on the 29th of
June and the 1st, 2d, and 3d of July. On the 30th of June it proceeded
to disinfect the commune of Darnac. The Mauvieres stove, in the first
place, disinfected the chief town of this commune on the 1st of July,
and on the next day it was taken to Poulets, a small hamlet, and a
dependent of the commune of Mauvieres. All the linen and all the
clothing of the sick of this locality, which had been the seat of
_sudor_, especially infantile, was disinfected. On the 4th of July,
the stove went to Concremiers, a commune about three miles distant,
and there finished up the disinfection that until then had been
performed in the ordinary way.

The epidemic was almost everywhere on the wane at this epoch; but we
judge that the test of the stoves was sufficient.

We are able to advance the following statement boldly: For the
application of disinfection in the rural districts, the movable stove
is the most practical thing that we know of. It is easily used, can be
taken to the smallest hamlets, and can be transported over the
roughest roads. It inspires peasants with no distrust. The first
repugnance is easily overcome, and every one, upon seeing that objects
come from the stove unharmed, soon hastens to bring to it all the
contaminated linen, etc., that he has in the house.

Further, we may add that the disinfection is accomplished in a quarter
of an hour, and that it therefore keeps the peasant but a very short
time from his work--an advantage that is greatly appreciated. Finally,
a day well employed suffices to disinfect a small settlement
completely. Upon the whole, disinfection by the stove under
consideration is the only method that can always and everywhere be
carried out.

We believe that it is called upon to render the greatest services in
the future.

The movable stove, regarding which Prof. Brouardel expresses himself
in the above terms, consists of a cylindrical chamber, 3½ feet in
internal diameter and 5 feet in length, closed in front by a
hermetically jointed door. This cylinder, which constitutes the
disinfection chamber, is mounted upon wheels and is provided with
shafts, so that it can easily be hauled by a horse or mule. The
cylinder is of riveted iron plate, and is covered with a wooden
jacket. The door is provided with a flange that enters a rubber lined
groove in the cylinder, and to it are riveted wrought iron forks that
receive the nuts of hinged bolts fixed upon the cylinder. The nuts are
screwed up tight, and the flange of the door, compressing the rubber
lining, renders the joint hermetical. The door, which is hinged, is
provided with a handle, which, when the stove is closed, slides over
an inclined plane fixed to the cylinder.

The steam enters a cast iron box in the stove through a rubber tube
provided with a threaded coupling. The entrance of the steam is
regulated by a cock. The box is provided with a safety and pressure
gauge and a small pinge cock. In the interior of the stove the
entrance of the steam is masked by a large tinned copper screen, which
is situated at the upper part and preserves the objects under
treatment from drops of water of condensation. These latter fall here
and there from the screen, follow the sides of the cylinder, and
collect at the bottom, from whence they are drawn off through a cock
placed in the rear.

The sides are lined internally with wood, which prevents the objects
to be infected from coming into contact with the metal. The objects to
be treated are placed upon wire cloth shelves. The pinge cock likewise
serves for drawing off the air or steam contained in the apparatus.

The stove is supported upon an axle through the intermedium of two
angle irons riveted longitudinally upon the cylinder. The axle is
cranked, and its wheels, which are of wood, are 4½ feet in diameter.
The shafts are fixed to the angle irons. The apparatus is, in
addition, provided with a seat, a brake, and prop rods before and
behind to keep it horizontal when in operation.

The boiler that supplies this stove is vertical and is mounted upon
four wheels. It is jacketed with wood, and is provided with a water
level, two gauge cocks, a pressure gauge, two spring safety valves, a
steam cock provided with a rubber tube that connects with that of the
stove, an ash pan, and a smoke stack. In the rear there are two
cylindrical water reservoirs that communicate with each other, and are
designed to feed the boiler through an injector. Beneath these
reservoirs there is a fuel box. In front there is a seat whose box
serves to hold tools and various other objects.--_La Nature._

       *       *       *       *       *




AN ELECTRICAL GOVERNOR.


We abstract the following from a paper on electric lighting by Prof.
J.A. Fleeming, read before the Iron and Steel Institute, Manchester.
The illustration is from _Engineering_.

[Illustration: ELECTRICAL GOVERNOR.]

One of the questions which most frequently occurs in reference to mill
and factory lighting is whether the factory engines can be used to run
the dynamo. As a broad, general rule, there can be no question that
the best results are obtained by using a separate dynamo engine,
controlled by a good governor, set apart for that purpose. With an
ordinary shunt dynamo, the speed ought not to vary more than 2 or 3
per cent. of its normal value on either side of that value. Hence, if
a dynamo has a normal speed of 1,000, it should certainly not vary
over a greater range than from 970 to 980 to 1,020 to 1,030. In many
cases there may be shafting from which the necessary power can be
taken, and of which the speed is variable only within these limits.
There are several devices by which it has been found possible to
enable a dynamo to maintain a constant electromotive force, even if
the speed of rotation varies over considerable limits. One of these is
that (see illustration) due to Messrs. Trotter & Ravenshaw, and
applicable to shunt or series machines.

In the circuit of the field magnet is placed a variable resistance.
This resistance is thrown in or out by means of a motor device
actuated by an electromotive force indicator. A plunger of soft iron
is suspended from a spring, and hangs within a solenoid of wire, which
solenoid is in connection with the terminals of the dynamo. Any
increase or diminution of the electromotive force causes this iron to
move in or out of the core, and its movement is made to connect or
disconnect the gearing which throws in the field magnet resistance
with a shaft driven by the engine itself. The principle of the
apparatus is therefore that small variations of electromotive force
are made to vary inversely the strength of the magnetic field through
the intervention of a relay mechanism in which the power required to
effect the movement is tapped from the engine.

With the aid of such a governor it is possible to drive a dynamo from
a mill shaft providing the requisite power, but of which the speed of
rotation is not sufficiently uniform to secure alone efficient
regulation of electromotive force. Another device, patented by Mr.
Crompton, is a modification of that method of field magnet winding
commonly known as compound winding. The field magnets are wound over
with two wires, one of which has a high resistance and is arranged as
a shunt, and the other of which has a low resistance and is arranged
in series. Instead, however, of the magnetizing powers of these coils
being united in the same direction as an ordinary compound winding,
they are opposed to one another. That is to say, the current in the
shunt wire tends to magnetize the iron of the field magnets in an
opposite direction to that of the series wire. It results from this
that any slight increase of speed diminishes the strength of the
magnetic field, and _vice versa_. Accordingly, within certain limits,
the electromotive force of the dynamo is independent of the speed of
rotation.

       *       *       *       *       *




THE ELECTRIC CURRENT AS A MEANS OF INCREASING THE TRACTIVE ADHESION OF
RAILWAY MOTORS AND OTHER ROLLING CONTACTS.[1]

  [Footnote 1: Read before the American Association for the
  Advancement of Science. New York meeting, 1887.]

By ELIAS E. RIES.


The object of this paper is to lay before you the results of some
recent experiments in a comparatively new field of operation, but one
that, judging from the results already attained, is destined to become
of great importance and value in its practical application to various
branches of industry.

I say "comparatively new" because the underlying principles involved
in the experiments referred to have, to a certain extent, been
employed (in, however, a somewhat restricted sense) for purposes
analogous to those that form the basis of this communication.

As indicated by the title, the subject that will now occupy our
attention is the use of the electric current as a means of increasing
and varying the frictional adhesion of rolling contacts and other
rubbing surfaces, and it is proposed to show how this effect may be
produced, both by means of the direct action of the current itself and
by its indirect action through the agency of electro-magnetism.

Probably the first instance in which the electric current was directly
employed to vary the amount of friction between two rubbing surfaces
was exemplified in Edison's electro-motograph, in which the variations
in the strength of a telephonic current caused corresponding
variations in friction between a revolving cylinder of moistened chalk
and the free end of an adjustable contact arm whose opposite extremity
was attached to the diaphragm of the receiving telephone. This device
was extremely sensitive to the least changes in current strength, and
if it were not for the complication introduced by the revolving
cylinder, it is very likely that it would to-day be more generally
used.

It has also been discovered more recently that in the operation of
electric railways in which the track rails form part of the circuit, a
considerable increase in the tractive adhesion of the driving wheels
is manifested, due to the passage of the return current from the
wheels into the track. In the Baltimore and Hampden electric railway,
using the Daft "third rail" system, this increased tractive adhesion
enables the motors to ascend without slipping a long grade of 350 feet
to the mile, drawing two heavily loaded cars, which result, it is
claimed, is not attainable by steam or other self-propelling motors of
similar weight. In the two instances just cited the conditions are
widely different, as regards the nature of the current employed, the
mechanical properties of the surfaces in contact, and the electrical
resistance and the working conditions of the respective circuits. In
both, however, as clearly demonstrated by the experiments hereinafter
referred to, the cause of the increased friction is substantially the
same.

In order to ascertain the practical value of the electric current as a
means of increasing mechanical friction, and, if possible, render it
commercially and practically useful wherever such additional friction
might be desirable, as for example in the transmission of power, etc.,
a series of experiments were entered into by the author, which, though
not yet fully completed, are sufficiently advanced to show that an
electric current, when properly applied, is capable of very materially
increasing the mechanical friction of rotating bodies, in some cases
as much as from 50 to 100 per cent., with a very economical
expenditure of current; this increase depending upon the nature of the
substances in contact and being capable of being raised by an
increased flow of current.

Before entering into a description of the means by which this result
is produced, and how it is proposed to apply this method practically
to railway and other purposes, it may be well to give a general
outline of what has so far been determined. These experiments have
shown that the coefficient of friction between two conducting surfaces
is very much increased by the passage therethrough of an electric
current of _low electromotive force and large volume_, and this is
especially noticeable between two rolling surfaces in peripheral
contact with each other, or between a rolling and a stationary
surface, as in the case of a driving wheel running upon a railway
rail. This effect increases with the number of amperes of current
flowing through the circuit, of which the two surfaces form part, and
is not materially affected by the electromotive force, so long as the
latter is sufficient to overcome the electrical resistance of the
circuit. This increase in frictional adhesion is principally
noticeable in iron, steel, and other metallic bodies, and is due to a
molecular change in the conducting substances at their point of
contact (which is also the point of greatest resistance in the
circuit), caused by the heat developed at that point. This heat is
ordinarily imperceptible, and becomes apparent only when the current
strength is largely augmented. It is therefore probable that a portion
of this increased tractive adhesion is due directly to the current
itself aside from its heating effect, although I have not as yet been
able to ascertain this definitely. The most economical and efficient
results have been obtained by the employment of a transformed current
of extremely low electromotive force (between ½ and 1 volt), but of
very large volume or quantity, this latter being variable at will, so
as to obtain different degrees of frictional resistance in the
substances under observation.

These experiments were originally directed mainly toward an endeavor
to increase the tractive adhesion of the driving wheels of locomotives
and other vehicles, and to utilize the electric current for this
purpose in such a manner as to render it entirely safe, practical, and
economical. It will be apparent at once that a method of increasing
the tractive power of the present steam locomotives by more than 50
per cent. without adding to their weight and without injury to the
roadbed and wheel tires, such as is caused by the sand now commonly
used, would prove of considerable value, and the same holds true with
respect to electrically propelled street cars, especially as it has
been found exceedingly difficult to secure sufficient tractive
adhesion on street railways during the winter season, as well as at
other times, on roads having grades of more than ordinary steepness.
As this, therefore, is probably the most important use for this
application of the electric current, it has been selected for
illustrating this paper.

I have here a model car and track arranged to show the equipment and
operation of the system as applied to railway motors. The current in
the present instance is one of alternating polarity which is converted
by this transformer into one having the required volume. The
electromotive force of this secondary current is somewhat higher than
is necessary. In practice it would be about half a volt. You will
notice upon a closer inspection that one of the forward driving wheels
is insulated from its axle, and the transformed current, after passing
to a regulating switch under the control of the engineer or driver,
goes to this insulated wheel, from which it enters the track rail,
then through the rear pair of driving wheels and axles to the opposite
rail, and then flows up through the forward uninsulated wheel, from
the axle of which it returns by way of a contact brush to the opposite
terminal of the secondary coil of the transformer. Thus the current is
made to flow _seriatim_ through all four of the driving wheels,
completing its circuit through that portion of the rails lying between
the two axles, and generating a sufficient amount of heat at each
point of contact to produce the molecular change before referred to.
By means of the regulating switch the engineer can control the amount
of current flowing at any time, and can even increase its strength to
such an extent, in wet or slippery weather, as to _evaporate any
moisture_ that may adhere to the surface of the rails at the point of
contact with the wheels while the locomotive or motor car is under
full speed.

It will be apparent that inasmuch as the "traction circuit" moves
along with the locomotive, and is complete through its driving wheel
base, the track rails in front and rear of the same are at all times
entirely free from current, _and no danger whatever can occur by
coming in contact with the rails between successive motors_. Moreover,
the potential used in the present arrangement, while sufficient to
overcome the extremely low resistance of the moving circuit, is too
small to cause an appreciable loss of current from that portion of the
rails in circuit, even under the most unfavorable conditions of the
weather. In practice the primary current necessary is preferably
generated by a small high speed alternating dynamo on the locomotive,
the current being converted by means of an inductional transformer. To
avoid the necessity for electrically bridging the rail joints, a
modified arrangement may be employed, in which the electrical
connection is made directly with a fixed collar on the forward and
rear driving axles, the current dividing itself in parallel between
the two rails in such a manner that, if a defective joint exists in
the rail at one side, the circuit is still complete through the rail
on the other; and as the rails usually break joints on opposite sides,
this arrangement is found very effective. The insulation of the
driving wheels is very easily effected in either case.

As the amount of additional tractive adhesion produced depends upon
the _quantity_ of current flowing rather than upon its pressure, the
reason for transforming the current as described will be apparent, and
its advantages over a direct current of higher tension and less
quantity, both from an economical and practical standpoint, will for
this reason be clear. The amount of heat produced at the point of
contact between the wheels and rails is never large enough to injure
or otherwise affect them, although it may be quite possible to
increase the current sufficiently to produce a very considerable
heating effect. The amount of current sent through the traction
circuit will of course vary with the requirements, and as the extent
to which the resistance to slipping may be increased is very great,
this method is likely to prove of considerable value. While in some
cases the use of such a method of increasing the tractive power of
locomotives would be confined to ascending gradients and the movement
of exceptionally heavy loads, in others it would prove useful as a
_constant_ factor in the work of transportation. In cases like that of
the New York elevated railway system, where the traffic during certain
hours is much beyond the capacity of the trains, and the structure
unable to support the weight of heavier engines, a system like that
just described would prove of very great benefit, as it would easily
enable the present engines to draw two or three additional cars with
far less slipping and lost motion than is the case with mechanical
friction alone, at a cost for tractive current that is insignificant
compared to the advantages gained. Other cases may be cited in which
this method of increasing friction will probably be found useful,
aside from its application to railway purposes, but these will
naturally suggest themselves and need not be further dwelt upon.

In the course of the experiments above described, another and somewhat
different method of increasing the traction of railway motors has been
devised, which is more particularly adapted to electric motors for
street railways, and is intended to be used in connection with a
system of electric street railways now being developed by the author.
In this system _electro-magnetism_ provides the means whereby the
increase in tractive adhesion is produced, and this result is attained
in an entirely novel manner. Several attempts have heretofore been
made to utilize magnetism for this purpose, but apparently without
success, chiefly because of the crude and imperfect manner in which
most of these attempts have been carried out.

The present system owes its efficiency to the formation of _a complete
and constantly closed magnetic circuit_, moving with the vehicle and
completed through the two driving axles, wheels, and that portion of
the track rails lying between the two pairs of wheels, in a manner
similar to that employed in the electrical method before shown. We
have here a model of a second motor car equipped with the apparatus,
mounted on a section of track and provided with means for measuring
the amount of tractive force exerted both with and without the passage
of the current.

You will notice that each axle of the motor car is wound with a helix
of insulated wire, the helices in the present instance being divided
to permit the attachment to the axles of the motor connections. The
helices on both axles are so connected that, when energized, they
induce magnetic lines of force that flow in the same direction through
the magnetic circuit. There are, therefore, four points at which the
circuit is maintained closed by the rolling wheels, and as the
resistance to the flow of the lines of force is greatest at these
points, the magnetic saturation there is more intense, and produces
the most effective result just where it is most required. Now, when
the battery circuit is closed through the helices, it will be observed
that the torque, or pull, exerted by the motor car is fully twice that
exerted by the motor with the traction circuit open, and, by
increasing the battery current until the saturation point of the iron
is reached, the tractive force is _increased nearly 200 per cent._, as
shown by the dynamometer. A large portion of this resistance to the
slipping or skidding of the driving wheels is undoubtedly due to
direct magnetic attraction between the wheels and track, this
attraction depending upon the degree of magnetic saturation and the
relative mass of metal involved.

But by far the greatest proportion of the increased friction is purely
the result of the change in position of the iron molecules due to the
well known action of magnetism, which causes a direct and close
_interlocking action_, so to speak, between the molecules of the two
surfaces in contact. This may be illustrated by drawing a very thin
knife blade over the poles of an ordinary electro-magnet, first with
the current on and then off.

In the model before you, the helices are fixed firmly to, and revolve
with, the axles, the connections being maintained by brushes bearing
upon contact rings at each end of the helices. If desired, however,
the axles may revolve loosely within the helices, and instead of the
latter being connected for cumulative effects, they may be arranged in
other ways so as to produce either subsequent or opposing magnetic
forces, leaving certain portions of the circuit neutral and
concentrating the lines of force wherever they maybe most desirable.
Such a disposition will prove of advantage in some cases.

The amount of current required to obtain this increased adhesion in
practice is extremely small, and may be entirely neglected when
compared to the great benefits derived. The system is very simple and
inexpensive, and the amount of traction secured is entirely within the
control of the motor man, as in the electric system. It will be seen
that the car here will not, with the traction circuit open, propel
itself up hill when one end of the track is raised more than 5 inches
above the table; but with the circuit energized it will readily ascend
the track as you now see it, with one end about 13½, inches above the
other in a length of three feet, _or the equivalent of a 40 per cent.
grade_; and this could be increased still further if the motor had
power enough to propel itself against the force of gravity on a
steeper incline. As you will notice, the motor adheres very firmly to
the track and requires a considerable push to force it down this 40
per cent. grade, whereas with the traction circuit open it slips down
in very short order, notwithstanding the efforts of the driving
mechanism to propel it up.

The resistance of the helices on this model is less than two ohms, and
this will scarcely be exceeded when applied to a full sized car, the
current from two or three cells of secondary batteries being probably
sufficient to energize them.

The revolution of the driving axles and wheels is not interfered with
in the slightest, because in the former the axle boxes are outside the
path of the lines of force, and in the case of the latter because each
wheel practically forms a single pole piece, and in revolving presents
continuously a new point of contact, of the same polarity, to the
rail; the flow of the lines of force being most intense through the
lower half of the wheels, and on a perpendicular line connecting the
center of the axle with the rail. In winter all that is necessary is
to provide each motor car with a suitable brush for cleaning the track
rails sufficiently to enable the wheels to make good contact
therewith, and any tendency to slipping or skidding may be effectually
checked. By this means it is easily possible to increase the tractive
adhesion of an ordinary railway motor from 50 to 100 per cent.,
without any increase in the load or weight upon the track; for it must
be remembered that even that portion of the increased friction due to
direct attraction does not increase the weight upon the roadbed, as
this attraction is mutual between the wheels and track rails; and if
this car and track were placed upon a scale and the circuit closed, it
would not weigh a single ounce more than with the circuit open.

It is obvious that this increase in friction between two moving
surfaces can also be applied to _check_, as well as augment, the
tractive power of a car or train of cars, and I have shown in
connection with this model a system of braking that is intended to be
used in conjunction with the electro-magnetic traction system just
described. You will have noticed that in the experiments with the
traction circuit the brake shoes here have remained idle; that is to
say, they have not been attracted to the magnetized wheels. This is
because a portion of the traction current has been circulating around
this coil on the iron brake beam, inducing in the brake shoes
magnetism of like polarity to that in the wheels to which they apply.
They have therefore been _repelled_ from the wheel tires instead of
being attracted to them. Suppose now that it is desired to stop the
motor car; instead of opening the traction circuit, the current
flowing through the helices is simply reversed by means of this pole
changing switch, whereupon the axles are magnetized in the opposite
direction and the brake shoes are instantly drawn to the wheels with a
very great pressure, as the current in the helices and brake coil now
assist each other in setting up a very strong magnetic flow,
sufficient to bring the motor car almost to an instant stop, if
desired.

The same tractive force that has previously been applied to increase
the tractive adhesion now exercises its influence upon the brake shoes
and wheels, with the result of not only causing a very powerful
pressure between the two surfaces due to the magnetic attraction, but
offering an extremely large frictional resistance in virtue of the
molecular interlocking action before referred to. As shown in the
present instance, a portion of the current still flows through the
traction circuit and prevents the skidding of the wheels.

The method thus described is equally applicable to increase the
coefficient of friction in apparatus for the transmission of power,
its chief advantage for this purpose being the ease and facility with
which the amount of friction between the wheels can be varied to suit
different requirements, or increased and diminished (either
automatically or manually) according to the nature of the work being
done. With soft iron contact surfaces the variation in friction is
very rapid and sensitive to slight changes in current strength, and
this fact may prove of value in connection with its application to
regulating and measuring apparatus. In all cases the point to be
observed is to maintain a closed magnetic circuit of low resistance
through the two or more surfaces the friction of which it is desired
to increase, and the same rule holds good with respect to the electric
system, except that in the latter case the best effects are obtained
when the area of surface in contact is smallest.

For large contact areas the magnetic system is found to be most
economical, and this system might possibly be used to advantage to
prevent slipping of short wire ropes and belts upon their driving
pulleys, in cases where longer belts are inapplicable as in the
driving of dynamos and other machinery. Experiments have also been,
and are still being, made with the object of increasing friction by
means of permanent magnetism, and also with a view to _diminishing_
the friction of revolving and other moving surfaces, the results of
which will probably form the subject matter of a subsequent paper.

Enough has been said to indicate that the development of these two
methods of increasing mechanical friction opens up a new and extensive
field of operation, and enables electricity to score another important
point in the present age of progress. The great range and flexibility
of this method peculiarly adapt it to the purposes we have considered
and to numerous others that will doubtless suggest themselves to you.
Its application to the increase of the tractive adhesion of railway
motors is probably its most prominent and valuable feature at present,
and is calculated to act as an important stimulus to the practical
introduction of electric railways on our city streets, inasmuch as the
claims heretofore made for cable traction in this respect are now no
longer exclusively its own. On trunk line railways the use of sand and
other objectionable traction-increasing appliances will be entirely
dispensed with, and locomotives will be enabled to run at greater
speed with less slipping of the wheels and less danger of derailment.
Their tractive power can be nearly doubled without any increase in
weight, enabling them to draw heavier trains and surmount steeper
grades without imposing additional weight or strain upon bridges and
other parts of the roadbed. Inertia of heavy trains can be more
readily overcome, loss of time due to slippery tracks obviated, and
the momentum of the train at full speed almost instantly checked by
_one and the same means_.

       *       *       *       *       *




ELECTRIC LAUNCH.


Trials have been made at Havre with an electric launch built to the
order of the French government by the Forges et Chantiers de la
Mediterranée. The vessel, which has rather full lines, measures 28 ft.
between perpendiculars and 9 ft. beam, and is 5 tons register.

The electromotor is the invention of Captain Krebs, who is already
well known on account of his experiments in connection with navigable
balloons, and of M. De Zédé, naval architect. The propeller shaft is
not directly coupled with the spindle of the motor, but is geared to
it by spur wheels in the ratio of 1 to 3, in order to allow of the
employment of a light high-speed motor. The latter makes 850
revolutions per minute, and develops 12 horse power when driving the
screw at 280 revolutions. Current is supplied by a new type of
accumulators made by Messrs. Commelin & Desmazures. One hundred and
thirty two of these accumulators are fitted in the bottom of the boat,
the total weight being about 2 tons.

In ordering this boat the French government stipulated a speed of 6
knots to be maintained during three hours with an expenditure of 10
horse power. The result of the trials gave a speed of 6½ knots during
five hours with 12 horse power, and sufficient charge was left in the
accumulators to allow the boat to travel on the following day for four
hours. This performance is exceedingly good, since it shows that one
horse power hour has been obtained with less than 60 lb. of total
weight of battery.

       *       *       *       *       *




THE COMMERCIAL EXCHANGE, PARIS.


Leveling the ground, pulling down old buildings, and distributing
light and air through her wide streets, Paris is slowly and
continuously pursuing her transformation. At this moment it is an
entire district, and not one of the least curious ones, that is
disappearing, leaving no other trace of its existence than the
circular walls that once inclosed the wheat market.

It is this building that, metamorphosed, is to become the Commercial
Exchange that has been so earnestly demanded since 1880 by the
commerce of Paris. The question, which was simple in the first place,
and consisted in the conversion of the wheat market into a commercial
exchange, became complicated by a project of enlarging the markets. It
therefore became necessary to take possession, on the one hand, of
sixty seven estates, of a total area of 116,715 square feet, to clear
the exchange, and, on the other, of 49,965 square feet to clear the
central markets. In other words, out of $5,000,000 voted by the common
council for this work, $2,800,000 are devoted to the dispossessions
necessitated by the new exchange, $1,800,000 to those necessitated by
the markets, and $400,000 are appropriated to the wheat market.

The work of demolition began last spring, and the odd number side of
Orleans street, Deux-Ecus street, from this latter to J.J. Rousseau
street, Babille street, Mercier street, and Sortine street, now no
longer exist. All this part is to-day but a desert, in whose center
stands the iron trussing of the wheat market cupola. It is on these
grounds that will be laid out the prolongation of Louvre street in a
straight line to Coquilliere street.

Our engraving shows the present state of the work. What is seen of the
wheat market will be preserved and utilized by Mr. Blondeau, the
architect, who has obtained a grant from the commercial exchange to
construct two edifices on two plots of an area of 32,220 square feet,
fronting on Louvre street, and which will bring the city an annual
rent of $60,000.

[Illustration: THE NEW COMMERCIAL EXCHANGE, PARIS.]

Around the rotunda that still exists there was a circular wall 6½ feet
in thickness. Mr. Blondeau has torn this down, and is now building
another one appropriate to the new destination of the acquired
estates. As for the trussing of the cupola, that is considered as a
work of art, and care has been taken not to touch it. It was
constructed at the beginning of this century, at an epoch when nothing
but rudimentary tools were to be had for working iron, and it was, so
to speak, forged. All the pieces were made with the hammer and were
added one to the other in succession. This cupola will be glazed at
the upper part, while the lower part will be covered with zinc. In the
interior this part will be decorated with allegorical paintings
representing the five divisions of the globe, with their commercial
and industrial attributes. It was feared at one time that the hall, to
which admission will be free, would not afford sufficient space, and
the halls of the Bordeaux and Havre exchanges were cited. It is true
that the hall of the wheat market has an area of but 11,825 square
feet, but on utilizing the 5,000 feet of the circular gallery, which
will not be occupied, it will reach 16,825 feet.

As for the tower which stands at one side of the edifice, that was
built by Marie de Medici for the astrologer whom she brought with her
to Paris from Florence. On account of its historic interest, this
structure will be preserved. On either side of this tower, overlooking
the roofs of the neighboring dwellings, are perceived the summit of a
tower of St. Eustache church and a campanile of a pavilion of the
markets.--_L'Illustration._

       *       *       *       *       *




THE MANUFACTURE OF COCAINE.


Cocaine is manufactured from the dry leaves of the _Erythroxylon
coca_, which grows in the valleys of the East Cordilleras of South
America--i.e., in the interior of Peru and Bolivia. The fresh leaves
contain 0.003 to 0.006 per cent of cocaine, which percentage decreases
considerably if the leaves are stored any length of time before being
worked up. On the other hand, the alkaloid can be transported and kept
without decomposition. This circumstance caused the author to devise a
simple process for the manufacture of crude cocaine on the spot,
neither Peru nor Bolivia being suitable countries for complicated
chemical operations. After many experiments, he hit upon the following
plan: The disintegrated coca leaves are digested at 70° C. in closed
vessels for two hours, with a very weak solution of sodium hydrate and
petroleum (boiling between 200° and 250° C). The mass is filtered,
pressed while still tepid, and the filtrate allowed to stand until the
oil has completely separated from the aqueous solution. The oil is
drawn off and carefully neutralized with very weak hydrochloric acid.
A white bulky precipitate of cocaine hydrochloride is obtained,
together with an aqueous solution of the same compound, while the
petroleum is free from the alkaloid and may be used for the extraction
of a fresh batch of leaves. The precipitate is dried, and by
concentrating the aqueous solution a further quantity of the
hydrochloride is obtained. Both can be shipped without risk of
decomposition. The product is not quite pure, but contains some
hygrine, traces of gum and other matters. Its percentage of alkaloid
is 75 per cent., while chemically pure cocaine hydrochloride
(C_{17}H_{21}NO_{4}.2HCl) contains 80.6 per cent. of the alkaloid. The
sodium hydrate solution cannot be replaced by milk of lime, nor can
any other acid be used for neutralization. Alcohol or ether are not
suitable for extraction. A repetition of the process with
once-extracted coca leaves gave no further quantity of cocaine,
proving that all the cocaine goes into solution by one treatment. The
same process serves on the small scale for the valuation of coca
leaves. 100 grms. of coca leaves are digested in a flask with 400 c.c.
of water, 50 c.c. of 1/10 NaOH (10 grms. of NaOH in 100 c.c.) and 250
c.c. of petroleum. The flask is loosely covered and warmed on the
water bath for two hours, shaking it from to time. The mass is then
filtered, the residue pressed, and the filtrate allowed to separate in
two layers. The oil layer is run into a bottle and titrated back with
1/100 HCl (1 grm. of HCl in 100 c.c.) until exactly neutral. The
number of c.c. of hydrochloric acid required for titrating back
multiplied by 0.42 gives the percentage of cocaine in the sample. The
following are some of the results with different samples of coca
leaves of various age:

                                            Contained per cent.
                                                 of Cocaine.
  Coca leaves from Mapiri, 1 month old             0.5% \
  "       "    "   Yungas    "     "               0.5%  |
  "       "    "   Mapiri and Yungas                     |
                          6 months old             0.4%  |    Of the
  "       "    "   Cuzco (Peru)                          |_ weight of
                          6 months old             0.3%  |   the dry
  "       "    "   Mapiri and Yungas                     |   leaves.
                          1 year old               0.3%  |
  "      "     "   Cuzco  " "    "                 0.2%  |
  "      "     "   Mapiri and Yungas                     |
                          2 years old              0.15%/

Coca leaves from Yungas and Cuzco, three years old, contained no trace
of the alkaloid, whereas fresh green leaves from Yungas contained 0.7
per cent. of the weight of the dry leaves. The same process is also
applicable for the manufacture of quinine from poor quinine bark, with
the single alteration that weak sulphuric acid must be used for the
neutralization of the alkaline petroleum extract.--_H.T. Pfeiffer,
Chem. Zeit. 11._

       *       *       *       *       *

[Continued from SUPPLEMENT, No. 622, page 9941.]




THE CHEMICAL BASIS OF PLANT FORMS.[1]

By HELEN C. DE S. ABBOTT.


The succession of plants from the lower to the higher forms will be
reviewed superficially, and chemical compounds noted where they
appear.

When the germinating spores of the fungi, _myxomycetes_, rupture their
walls and become masses of naked protoplasm, they are known as
plasmodia. The plasmodium _Æthalium septicum_ occurs in moist places,
on heaps of tan or decaying barks. It is a soft, gelatinous mass of
yellowish color, sometimes measuring several inches in length.

The plasmodium[2] has been chemically analyzed, though not in a state
of absolute purity. The table of Reinke and Rodewold gives an idea of
its proximate constitution.

Many of the constituents given are always present in the living cells
of higher plants. It cannot be too emphatically stated that where
"biotic" force is manifested, these colloidal or albuminous compounds
are found.

The simplest form of plant life is an undifferentiated individual, all
of its functions being performed indifferently by all parts of its
protoplasm.

The chemical basis of plasmodium is almost entirely composed of
complex albuminous substances, and correlated with this structureless
body are other compounds derived from them. Aside from the chemical
substances which are always present in living matter, and are
essential properties of protoplasm, we find no other compounds. In the
higher organisms, where these functions are not performed
indifferently, specialization of tissues is accompanied by many other
kinds of bodies.

The algæ are a stage higher in the evolutionary scale than the
undifferentiated noncellular plasmodium. The simple _Alga
protococcus_[3] may be regarded as a simple cell. All higher plants
are masses of cells, varying in form, function, and chemical
composition.

A typical living cell may be described as composed of a cell wall and
contents. The cell wall is a firm, elastic membrane closed on all
sides, and consists mainly of cellulose, water, and inorganic
constituents. The contents consist of a semi-fluid colloidal
substance, lying in contact with the inner surface of the membrane,
and, like it, closed on all sides. This always is composed of
albuminous substances. In the higher plants, at least, a nucleus
occurs embedded in it; a watery liquid holding salts and saccharine
substances in solution fills the space called the vacuole, inclosed by
the protoplasm.

These simple plants may be seen as actively moving cells or as
non-motile cells. The former consist of a minute mass of protoplasm,
granular and mostly colored green, but clear and colorless at the more
pointed end, and where it is prolonged into two delicate filaments
called cilia. After moving actively for a time they come to rest,
acquire a spherical form, and invest themselves with a firm membrane
of cellulose. This firm, outer membrane of the _Protococcus_
accompanies a higher differentiation of tissue and localization of
function than is found in the plasmodium.

_Hæatococcus_ and plasmodium come under the classes algæ and fungi of
the Thallothyta group. The division[4] of this group into two classes
is based upon the presence of chlorophyl in algæ and its absence in
fungi. Gelatinous starch is found in the algæ; the fungi contain a
starchy substance called glycogen, which also occurs in the liver and
muscles of animals. Structureless bodies, as _æthalium_, contain no
true sugar. Stratified starch[5] first appears in the phanerogams.
Alkaloids have been found in fungi, and owe their presence doubtless
to the richness of these plants in nitrogenous bodies.

In addition to the green coloring matter in algæ are found other
coloring matters.[6] The nature[7] of these coloring matters is
usually the same through whole families, which also resemble each
other in their modes of reproduction.

In form, the algæ differ greatly from filaments or masses of cells;
they live in the water and cover damp surfaces of rocks and wood. In
these they are remarkable for their ramifications and colors and grow
to a gigantic size.

The physiological functions of algæ and fungi depend upon their
chemical differences.

These facts have been offered, simple as they are, as striking
examples of chemical and structural opposition.

The fungi include very simple organisms, as well as others of
tolerably high development, of most varied form, from the simple
bacillus and yeast to the truffle, lichens, and mushrooms.

The cell membrane of this class contains no pure cellulose, but a
modification called fungus cellulose. The membrane also contains an
amyloid substance, amylomycin.[8] Many of the chemical constituents
found in the entire class are given in _Die Pflanzenstoffe_.[9]

Under the _Schizomycetes_ to which the _Micrococcus_ and
_Bacterium_[10] belong are found minute organisms differing much in
form and in the coloring[11] matters they produce, as that causing the
red color of mouldy bread.

The class of lichens[12] contains a number of different coloring
substances, whose chemical composition has been examined. These
substances are found separately in individuals differing in form. In
the _Polyporus_[13] an acid has been found peculiar to it, as in many
plants special compounds are found. In the agariceæ the different
kinds of vellum distinguish between species, and the color of the
conidia is also of differential importance. In all cases of distinct
characteristic habits of reproduction and form, one or more different
chemical compounds is found.

In the next group of the musiceæ, or mosses, is an absence of some
chemical compounds that were characteristic of the classes just
described. Many of the albuminous substances are present. Starch[14]
is found often in large quantities, and also oily fats, which are
contained in the oil bodies of the liverworts; wax,[15] organic acids,
including aconitic acid, and tannin, which is found for the first time
at this evolutionary stage of the plant kingdom.

The vascular cryptogams are especially characterized by their mineral
composition.[16] The ash is extraordinarily rich in silicic acid and
alumina.

  Equisetum[17]..........silicic acid     60 per cent.
  Aspidium...............  "     "        13
  Asplenium..............  "     "        35
  Osmunda................  "     "        53
  Lycopodium[18].........  "     "        14
       "         ........ alumina   26 to 27
       "         ........ manganese 2 to 2.5

These various plants contain acids and compounds peculiar to
themselves.

As we ascend in the plant scale, we reach the phanerogams. These
plants are characterized by the production of true seeds, and many
chemical compounds not found in lower plants.

It will be convenient in speaking of these higher groups to follow M.
Heckel's[19] scheme of plant evolution. All these plants are grouped
under three main divisions: apetalous, monocotyledonous, and
dicotyledonous; and these main divisions are further subdivided.

It will be observed that these three main parallel columns are divided
into three general horizontal planes.

On plane 1 are all plants of simplicity of floral elements, or parts;
for example, the black walnut, with the simple flower contained in a
catkin.

On plane 2 plants which have a multiplicity of floral elements, as the
many petals and stamens of the rose; and finally, the higher plants,
the orchids among the monocotyledons and the composite among the
dicotyledonous plants, come under the third division of condensation
of floral elements.

It will be impossible to take up in order for chemical consideration
all these groups, and I shall restrict myself to pointing out the
occurrence of certain constituents.

I desire now to call attention to chemical groups under the apetalous
plants having simplicity of floral elements.

_Cassuarina equisetifolia_[20] possibly contains tannin, since it is
used for curing hides. The bark contains a dye. It is said to resemble
_Equisetum_[21] in appearance, and in this latter plant a yellow dye
is found.

The _Myrica_[22] contains ethereal oil, wax, resin, balsam, in all
parts of the plant. The root contains in addition fats, tannin, and
starch, also myricinic acid.

In the willow and poplar,[23] a crystalline, bitter substance, salicin
or populin, is found. This may be considered as the first appearance
of a real glucoside, if tannin be excluded from the list.

The oak, walnut, beech, alder, and birch contain tannin in large
quantities; in the case of the oak, ten to twelve per cent. Oak galls
yield as much as seventy per cent.[24]

The numerous genera of pine and fir trees are remarkable for ethereal
oil, resin, and camphor.

The plane[25] trees contain caoutchouc and gum; peppers,[26] ethereal
oils, alkaloids, piperin, white resin, and malic acid. _Datisca
cannabina_[27] contains a coloring matter and another substance
peculiar to itself, datiscin, a kind of starch, or allied to the
glucosides.

Upon the same evolutionary plane among the monocotyledons, the dates
and palms[28] contain in large quantities special starches, and this
is in harmony with the principles of the theory. Alkaloids and
glucosides have not yet been discovered in them.

Other monocotyledonous groups with simplicity of floral elements, such
as the typhaceæ, contain large quantities of starch; in the case of
_Typha latifolia_[29] 12.5 per cent., and 1.5 per cent. gum. In the
pollen of this same plant, 2.08 per cent. starch has been found.

Under the dicotyledonous groups, there are no plants with simplicity
of floral elements.

Returning, now, to apetalous plants of multiplicity and simplification
of floral elements, we find that the urticaceæ[30] contain free formic
acid; the hemp[31] contains alkaloids; the hop,[32] ethereal oil and
resin; the rhubarb,[33] crysophonic acid; and the begonias,[34]
chicarin and lapacho dyes. The highest apetalous plants contain
camphors and oils; the highest of the monocotyledons contain a
mucilage and oils; and the highest dicotyledons contain oils and
special acids.

The trees yielding common camphor and borneol are from genera of the
lauraceæ family; also sassafras camphor is from the same family. Small
quantities of stereoptenes are widely distributed through the plant
kingdom.

The gramineæ, or grasses, are especially characterized by the large
quantities of sugar and silica they contain. The ash of the rice hull,
for example, contains ninety eight per cent. silica.

The ranunculaceæ contain many plants which yield alkaloids, as
_Hydrastia canadensis_, or Indian hemp, _Helleborus_, _Delphinum_,
_Aconitum_, and the alkaloid berberine has been obtained from genera
of this family.

The alkaloid[35] furnishing families belong, with few exceptions, to
the dicotyledons. The colchiceæ, from which is obtained veratrine,
form an exception among the monocotyledons. The alkaloids of the
fungus have already been noted.

[36]Among the greater number of plant families, no alkaloids have been
found. In the labiatæ none has been discovered, nor in the compositæ
among the highest plants.

One alkaloid is found in many genera of the loganiaceæ; berberine in
genera of the berberidaceæ, ranunculaceæ, menispermaceæ, rutaceæ,
papaveraceæ, anonaceæ.

Waxes are widely distributed in plants. They occur in quantities in
some closely related families.

Ethereal oils occur in many families, in the bark, root, wood, leaf,
flower, and fruit; particularly in myrtaceæ, laurineæ, cyperaceæ,
crucifereæ, aurantiaceæ, labiatæ, and umbelliferæ.

Resins are found in most of the higher plants. Tropical plants are
richer in resins than those of cold climates.

Chemical resemblance between groups, as indicating morphological
relations, has been well shown. For example: the similarity[37] of the
viscid juices, and a like taste and smell, among cactaceæ and
portulaceæ, indicate a closer relationship between these two orders
than botanical classification would perhaps allow. This fact was
corroborated by the discovery of irritable stamens in _Portulaca_ and
_Opuntia_, and other genera of cactaceæ.

Darwin[38] states that in the compositæ the ray florets are more
poisonous than the disk florets, in the ratio of about 3 to 2.

Comparing the cycadeæ and palmæ, the former are differently placed by
different botanists, but the general resemblance is remarkable, and
they both yield sago.

Chemical constituents of plants are found in varying quantities during
stated periods of the year. Certain compounds present at one stage of
growth are absent at another. Many facts could be brought forward to
show the different chemical composition of plants in different stages
of growth. The _Thuja occidentalis_[39] in the juvenescent and adult
form, offers an example where morphological and chemical differences
go hand in hand. Analyses of this plant under both conditions show a
striking difference.

Different parts of plants may contain distinct chemical compounds, and
the comparative chemical study of plant orders comprises the analysis
of all parts of plants of different species.

For example; four portions of the _Yucca angustifolia_[40] were
examined chemically; the bark and wood of the root and the base and
blades of the leaves. Fixed oils were separated from each part. These
were not identical; two were fluid at ordinary temperature, and two
were solid. Their melting and solidifying points were not the same.

This difference in the physical character and chemical reaction of
these fixed oils may be due to the presence of free fatty acid and
glycerides in varying proportions in the four parts of the plants. It
is of interest to note that, in the subterranean part of the _Yucca_,
the oil extracted from the bark is solid at the ordinary temperature;
from the wood it was of a less solid consistency; while the yellow
base of the leaf contained an oil quite soft, and in the green leaf
the oil is almost fluid.

Two new resins were extracted from the yellow and green parts of the
leaf. It was proposed to name them _yuccal_ and _pyrophæal_ An
examination of the contents of each extract showed a different
quantitative and qualitative result.

Saponin was found in all parts of the plant.

Many of the above facts have been collected from the investigations of
others. I have introduced these statements, selected from a mass of
material, as evidences in favor of the view stated at the beginning of
this paper.[41] My own study has been directed toward the discovery of
saponin in those plants where it was presumably to be found. The
practical use of this theory in plant analysis will lead the chemists
at once to a search for those compounds which morphology shows are
probably present.

I have discovered saponin in all parts of the _Yucca angustifolia_, in
the _Y. filimentosa_ and _Y. gloriosa_, in several species of agavæ,
and in plants belonging to the leguminosæ family.

The list[42] of plants in which saponin has been discovered is given
in the note. All these plants are contained in the middle plane of
Heckel's scheme. No plants containing saponin have been found among
apetalous groups. No plants have been found containing saponin among
the lower monocotyledons.

The plane of saponin passes from the liliaceæ and allied groups to the
rosales and higher dicotyledons.

Saponin belongs to a class of substances called glucosides. Under the
action of dilute acids, it is split up into two substances, glucose
and sopogenin. The chemical nature of this substance is not thoroughly
understood. The commercial[43] product is probably a mixture of
several substances.

This complexity of chemical composition of saponin is admirably
adapted for the nutrition of the plant, and it is associated with the
corresponding complexity of the morphological elements of the plant's
organs. According to M. Perrey,[44] it seems that the power of a plant
to direct the distribution of its carbon, hydrogen, and oxygen to form
complex glucosides is indicative of its higher functions and
developments.

The solvent action of saponin on resins has been already discussed.
Saponin likewise acts as a solvent upon barium[45] sulphate and
calcium[46] oxalate, and as a solvent of insoluble or slightly soluble
salts would assist the plant in obtaining food, otherwise difficult of
access.

The botanical classifications based upon morphology are so frequently
Saponin is found in endogens and exogens. The line dividing these two
groups is not always clearly defined. Statements pointing to this are
found in the works of Haeckel, Bentham, and others.

Smilax belongs to a transition class, partaking somewhat of the nature
of endogen and of exogen. It is worthy of note that this intermediate
group of the sarsaparillas should contain saponin.

It is a significant fact that all the groups above named containing
saponin belong to Heckel's middle division.

It may be suggested that saponin is thus a constructive element in
developing the plant from the multiplicity of floral elements to the
cephalization of those organs.

It has been observed that the composite occurs where the materials for
growth are supplied in greatest abundance, and the more simple forms
arise where sources of nutrition are remote. We may gather from this
fact that the simpler organs of plants low in the evolutionary scale
contain simpler non-nitrogenous chemical compounds for their
nutrition.

The presence of saponin seems essential to the life of the plant where
it is found, and it is an indispensable principle in the progression
of certain lines of plants, passing from their lower to their higher
stages.

Saponin is invariably absent where the floral elements are simple; it
is invariably absent where the floral elements are condensed to their
greatest extent. Its position is plainly that of a factor in the great
middle realm of vegetable life, where the elements of the individual
are striving to condense, and thus increase their physiological action
and the economy of parts.

It may be suggested as a line of research to study what are the
conditions which control the synthesis and gradual formation of
saponin in plants. The simpler compounds of which this complex
substance is built up, if located as compounds of lower plants, would
indicate the lines of progression from the lower to the saponin
groups.

In my paper[47] read in Buffalo at the last meeting of the American
Association for the Advancement of Science, various suggestions were
offered why chemical compounds should be used as a means of botanical
classification.

The botanical classifications based upon morphology are so frequently
unsatisfactory, that efforts in some directions have been made to
introduce other methods.[48]

There has been comparatively little study of the chemical principles
of plants from a purely botanical view. It promises to become a new
field of research.

The leguminosæ are conspicuous as furnishing us with important dyes,
e.g., indigo, logwood, catechin. The former is obtained principally
from different species of the genus _Indigofera_, and logwood from the
_Hæmatoxylon_ and _Saraca indica_.

The discovery[49] of hæmatoxylin in the _Saraca indica_ illustrates
very well how this plant in its chemical, as well as botanical,
character is related to the _Hæmatoxylon campechianum_; also, I found
a substance like catechin in the _Saraca_. This compound is found in
the _acacias_, to which class _Saraca_ is related by its chemical
position, as well as botanically. Saponin is found in both of these
plants, as well as in many other plants of the leguminosæ. The
leguminosæ come under the middle plane or multiplicity of floral
elements, and the presence of saponin in these plants was to be
expected.

From many of the facts above stated, it may be inferred that the
chemical compounds of plants do not occur at random. Each stage of
growth and development has its own particular chemistry.

It is said that many of the constituents found in plants are the
result of destructive metabolism, and are of no further use in the
plant's economy. This subject is by no means settled, and even should
we be forced to accept that ground, it is a significant fact that
certain cells, tissues, or organs peculiar to a plant secrete or
excrete chemical compounds peculiar to them, which are to be found in
one family, or in species closely allied to it.

It is a fact that the chemical compounds are there, no matter why or
whence they came. They will serve our purposes of study and
classification.

The result of experiment shows that the presence of certain compounds
is essential to the vigor and development of all plants and particular
compounds to the development of certain plants. Plant chemistry and
morphology are related. Future investigations will demonstrate this
relation.

In general terms, we may say that amides and carbohydrates are
utilized in the manufacture of proteids. Organic acids cause a
turgescence of cells. Glucosides may be a form of reserve food
material.

Resins and waxes may serve only as protection to the surfaces of
plants; coloring matters, as screens to shut off or admit certain of
the sun's rays; but we are still far from penetrating the mystery of
life.

A simple plant does what animals more highly endowed cannot do. From
simplest substances they manufacture the most complex. We owe our
existence to plants, as they do theirs to the air and soil.

The elements carbon, oxygen, hydrogen, and nitrogen pass through a
cycle of changes from simple inorganic substances to the complex
compounds of the living cell. Upon the decomposition of these bodies
the elements return to their original state. During this transition
those properties of protoplasm which were mentioned at the beginning,
in turn, follow their path. From germination to death this course
appears like a crescent, the other half of the circle closed from
view. Where chemistry begins and ends it is difficult to say.--_Jour.
Fr. Inst._

  [Footnote 1: A lecture delivered before the Franklin Institute,
  January 24, 1887.]

  [Footnote 2: Studien uber das Protoplasm, 1881.]

  [Footnote 3: Vines, p. 1. Rostafinski: Mem. de la Soc. des Sc.
  Nat. de Cherbourg, 1875. Strasburger: Zeitschr., xii, 1878.]

  [Footnote 4: Botany: Prantl and Vines. London, 1886, p. 110.]

  [Footnote 5: For the literature of starch, see p. 115, Die
  Pflanzenstoffe, von Hilger and Husemann.]

  [Footnote 6: Kutzing: Arch. Pharm., xli, 38. Kraus and Millardet:
  Bul. Soc. Sciences Nat., Strasbourg, 1868, 22. Sorby: Jour. Lin.
  Soc., xv, 34. J. Reinke: Jahrb. Wissenscht. Botan., x, B. 399.
  Phipson: Phar. Jour. Trans., clxii, 479.]

  [Footnote 7: Prantl and Vines, p. 111.]

  [Footnote 8: L. Crie: Compt. Rend., lxxxviii, 759 and 985. J. De
  Seynes, 820, 1043.]

  [Footnote 9: Page 279.]

  [Footnote 10: M. Nencki and F. Schaffer. N. Sieher: Jour. Pract.
  Chem., 23, 412.]

  [Footnote 11: E. Klein: Quar. Jour. Micros. Science, 1875, 381. O.
  Helm: Arch. Pharm., 1875, 19-24. G. Gugini: Gaz. Chem., 7, 4. W.
  Thorner: Bul. Ber, xi, 533.]

  [Footnote 12: Handbook of Dyeing. By W. Crookes, London, 1874. p. 367.
  Schunck: Ann. Chem. Pharm., 41, 157; 54, 261; 61, 72; 61, 64; 61, 78.
  Rochelder and Heldt, ibid., 48, 2; 48, 9. Stenhouse, ibid., 68, 57;
  68, 72; 68, 97, 104; 125, 353. See also researches of Strecker, O.
  Hesse, Reymann, Liebermann, Lamparter, Knop, and Schnedermann.]

  [Footnote 13: Stahlschmidt.]

  [Footnote 14: E. Treffner: Inaugur. Diss. Dorpat, 1880.]

  [Footnote 15: W. Pfeffer: Flora, 1874.]

  [Footnote 16: Die Pflanzenstoffe, p. 323 W. Lange: Bul. Ber., xi,
  822.]

  [Footnote 17: Ann. Chim. Phys., 41, 62, 208; Ann. Chim. Pharm.,
  77, 295.]

  [Footnote 18: Fluckiger: Pharmakognosie. Kamp: Ann. Chim. Pharm.,
  100, 300.]

  [Footnote 19: Revue Scientifiqe, 13 Mars, 1886.]

  [Footnote 20: Dictionary of Economic Plants. By J. Smith. London,
  1882, p. 294.]

  [Footnote 21: Ibid., p. 160. Pharmakognosie des Pflanzenreichs,
  Wittstein, p. 736. Ann. Chem. Pharm., 77, 295.]

  [Footnote 22: Rabenhorst: Repert. Pharm., lx, 214. Moore: Chem.
  Centralbl., 1862, 779, Dana.]

  [Footnote 23: Johansen: Arch. Pharm., 3, ix, 210. Ibid., 3, ix
  103. Bente: Berl. Ber., viii, 476. Braconnot: Ann. Chim. Phys., 2,
  44, 296.]

  [Footnote 24: Wittstein; Pharm. des Pflanzenreichs, p. 249.]

  [Footnote 25: John; Ibid., p. 651.]

  [Footnote 26: Dulong. Oersted, Lucas, Pontet; Ibid., p. 640.]

  [Footnote 27: Braconnot: Ann. Chim. Phys., 2, 3. 277. Stenhouse:
  Ann. Chim. Phann., 198, 166].

  [Footnote 28: 3 Pflanzenstoffe, p. 412.]

  [Footnote 29: Lecocq: Braconnot: Pharmacog. Pflan, p. 693.]

  [Footnote 30: Gorup-Besanez.]

  [Footnote 31: Siebold and Brodbury: Phar. Jour. Trans., 3, 590,
  1881, 326.]

  [Footnote 32: Wagner: Jour. Prakt. Chem., 58, 352. B. Peters, v.
  Gohren: Jahresb. Agric., viii, 114; ix, 105; v. 58. Ann. Jour.
  Pharm., 4, 49.]

  [Footnote 33: Dragendorff: Pharm. Zeitschr. Russ., xvii, 65-97.]

  [Footnote 34: Bonssingault: Ann. Chim. Phys., 2, 27, 315. Erdmann:
  Jour. Pract. Chem., 71, 198.]

  [Footnote 35: Die Pflanzenstoffe, p. 21.]

  [Footnote 36: Ibid.]

  [Footnote 37: Meehan: Proc. Acad. Nat. Sciences.]

  [Footnote 38: Different forms of flowers on plants of the same
  species. Introduction.]

  [Footnote 39: Meehan: Proc. Acad. Nat. Sciences.]

  [Footnote 40: H.C. De S. Abbott: Trans. Amer. Philos. Soc., 1886.]

  [Footnote 41: For further facts confirming this theory, see
  "Comparative Chemistry of Higher and Lower Plants." By H.C. De S.
  Abbott. Amer. Naturalist, August, 1887.]

  [Footnote 42: Different genera and species of the following:
  Ranunculaceæ, Berberidaceæ, Carophyllaceæ, Polygalaceæ,
  Bromeliaceæ, Liliaceæ, Smilaceæ, Yuccas, Amaryllideæ, Leguminosæ,
  Primulaceæ, Rosaceæ, Sapindaceæ, Sapotaceæ]

  [Footnote 43: Kobert: Chem Ztg.]

  [Footnote 44: Compt. Rend., xciv, p. 1124.]

  [Footnote 45: Bul. de la Soc. Chim.]

  [Footnote 46: "Yucca angus." Trans. Am. Philos. Soc., Dec., 1885.]

  [Footnote 47: Botanical Gazette, October, 1886.]

  [Footnote 48: Borodin: Pharm. Jour. Trans., xvi, 369. Pax. Firemy:
  Ann. Sci. Nat., xiii.]

  [Footnote 49: H.C. De S. Abbott, Proc. Acad. Nat. Sciences, Nov.
  30, 1886.]

       *       *       *       *       *




NEW METHOD FOR THE QUANTITATIVE DETERMINATION OF STARCH.

A.V. ASBOTH.


The author maintains that unsatisfactory results are obtained in
determinations of starch when the method employed is based upon the
inversion of sugar, formed as an intermediate product, since maltose,
dextrose, and levulose are partly decomposed by boiling with dilute
acids. He proposes to replace the methods hitherto employed by one
which depends upon the formation of a barium salt of starch, to which
he assigns the formula BaO.C_{24}H_{40}O_{20}. This salt is sparingly
soluble in water and insoluble in dilute alcohol.

In making a determination a weighed quantity of starch is saccharified
with water, then mixed with an excess of normal baryta solution,
dilute alcohol added to make up to a certain volume, and, after the
precipitate has settled, the excess of baryta is titrated back with
acid.

[Illustration: Titrating apparatus]

The author also describes the apparatus he employs for storing and
titrating with baryta solution. The latter is contained in the bottle,
A, and the drying tube attached to the neck of the same is filled with
quicklime. The burette, B, which is in direct connection with the
bottle, may be filled with the solution by opening the stop cock, and
the small drying tube, _n_, is filled with dry KOH, thus preventing
the entrance of any CO_{2}. Numbers are appended which seem to testify
to the excellence of the method employed. The author finally gives a
detailed account of the entire analysis of various cereals.--_A.R. in
Jour. Soc. Chem. Indus._

       *       *       *       *       *




SYNTHESIS OF THE ALKALOIDS.


In the note on the constitution of alkaloids in a recent issue, we
referred more especially to what we may term the less highly organized
bases. Most of our knowledge, as we now have it, regarding such
alkaloids as muscarine and choline has been acquired during the past
dozen years. This is not exactly the case with the higher groups of
alkaloids--the derivatives of pyridine and quinoline. It so happens
that the oldest alkaloids are in these groups. They have, almost
necessarily, been subjected to a longer period of attack, but the
extreme complexity of their molecules, and the infinite number of
differing parts or substances into which these molecules split up when
attacked, are the main cause of the small progress which has been made
in this department. All, however, yield one or more bodies or bases in
common, while each has its distinctive and peculiar decomposition
product. For example, cinchonine and quinine both afford the basic
quinoline under certain conditions, but on oxidation of cinchonine, an
acid--cinchoninic acid (C_{10}H_{7}NO_{2})--is the principal body
formed, while in the case of quinine, quininic acid (C_{10}H_{9}NO_{3})
is the principal product. The acquirement through experiment of such
knowledge as that is, however, so much gained. We find, indeed, that
obstacles are gradually being cleared away, and the actual synthetic
formation of such alkaloids as piperidine and coniine is a proof that
the chemist is on the right track in studying the decomposition
products, and building up from them, theoretically, bodies of similar
constitution. It is noteworthy that the synthesis of the alkaloids has
led to some of the most brilliant discoveries of the present day,
especially in the discovery of dye stuffs. Many of our quinine
substitutes, such as thalline, for example, are the result of
endeavors to make quinine artificially. If there is romance in
chemistry at all, it is to be found certainly in this branch of it,
which is generally considered the most uninteresting and unfathomable.
We may take piperidine and coniine as examples of the methods followed
in alkaloidal synthesis; these are pyridine bases. Pyridine has the
formula C_{5}H_{5}N, that is, it is benzene with CH replaced by N. The
relationship between these and piperidine is seen in the following
formulæ:

       CH            N                NH
      /  \          /  \             /  \
    HC    CH      HC    CH     H_{2}C    CH_{2}
     |    |        |    |           |    |
    HC    CH      HC    CH     H_{2}C    CH_{2}
      \  /          \  /             \  /
       CH            CH               CH_{2}

    (Benzene,)    (Pyridine,)    (Piperidine,)
    (C_{6}H_{6})  (C_{5}H_{5}N)  (C_{5}H_{11}N)

If we introduce six hydrogen atoms into pyridine, we convert it into
piperidine. Ladenburg succeeded in so hydrogenizing pyridine by acting
upon an alcoholic solution with sodium, and from the base which was
formed he obtained a platinochloride which agreed with the similar
double salt of piperidine. He has also prepared it from trimethyline
cyanide by the action of sodium. Pentamethylinediamine is the
principal intermediary product, and this gives piperidine when
distilled with superheated steam. He has proved that the alkaloid so
obtained is identical with that prepared from piperine. Another
curious point which Ladenburg has lately proved is that cadaverine
(one of the products of flesh decomposition) is identical with
pentamethylinediamine, and that its imine is the same as piperidine.
The synthesis of coniine by Ladenburg is one of the most notable
achievements of modern chemistry. He at first supposed that this
alkaloid was piperidine in which two hydrogen atoms were replaced by
the isopropyl radical (C_{3}H_{7}), its formula being taken as
C_{5}H_{9}(C_{3}H_{7})NH. But he has since changed his view, as will
be seen from what follows. In its synthesis 1,000 grammes of picoline
were first converted into alphapicoline, 380 grammes being obtained.
This was heated with paraldehyde, whereby it was converted into
allylpyridine (48 grammes), and this by reduction with sodium yielded
alpha-propylpyridine, a body in almost every respect identical with
coniine. The more important difference was its optical inactivity, but
he succeeded in splitting up a solution of the acid tartrate of the
base by means of _Penicillium glaucum_. Crystals separated which had a
dextro-rotatory power of [_a_]_{D} = 31° 87' as compared with the
[_a_]_{D} = 13° 79' of natural coniine. This brief account conveys but
a faint idea of the difficulties which were encountered in these
researches. Optical methods of examination have proved of great value,
and are destined to play an important part in such work.

Among the most complex alkaloids are those of the quinine group. As
yet chemists have got no further with these than the oxidation
products; but the study has afforded us several new antipyretics and
many interesting facts. It has been found, for example, that
artificial quinine-like bodies, which fluoresce and give the green
color with chlorine water and ammonia, have antipyretic properties
like quinine, but their secondary effects are so pernicious as to
prevent their use. If, however, such bodies are hydrogenized or
methylated they lose their fluorescing property, do not give the green
color, and their secondary effects are removed. Knowledge of these
facts led to the discovery of thalline. It is prepared from
paraquinanisol, one of the objectionable bodies, by reduction with tin
and hydrochloric acid. The following formulæ show the constitutional
relationship of these compounds:

               CH   CH                  CH   CH_{2}
              /  \ /  \                /  \ /  \
    (CH_{3}O)C    C    CH    (CH_{3}O)C    C    CH_{2}
             |    |    |              |    |    |
            HC    C    CH            HC    C    CH_{2}
              \  / \  /                \  / \  /
               CH   N                   CH   NH

            Paraquinanisol              Thalline
          C_{9}H_{6}.CH_{3}.NO.     C_{9}H_{10}.CH_{3}.NO.

It is evident from the difficulties which have been encountered in
this department of chemistry, and more especially from the costly
nature of the work, that it will be many years before it will
influence the manufacture of alkaloids from the drugs which yield
them. Ladenburg has synthetized coniine, but he has not yet ventured
to assert that his product will replace the natural alkaloid.--_Chem.
and Druggist._

       *       *       *       *       *


The _Southern California Advocate_ reports another magnificent
donation of lands to the University of Southern California by Mr. D.
Freeman, the owner of the Centinella ranch near Los Angeles--six
hundred thousand dollars in all given to found a school of applied
sciences, $100,000 for building and apparatus and $500,000 for
endowment. The buildings will be in the vicinity of Inglewood, the new
and beautiful town on the Ballona branch of the California Central.

       *       *       *       *       *




A GROUP OF HAMPSHIRE DOWNS.


[Illustration]

The Hampshire Down breed of sheep originated about 80 years ago by a
cross of South Downs on the horned, white-faced sheep which had for
ages been native of the open, untilled, hilly stretch of land known as
the Hampshire Downs, in the county of that name bordering on the
English Channel, in the South of England. From time immemorial the
South Downs had dark brown or black legs, matured early, produced the
best of mutton and a fine quality of medium wool. The original
Hampshire was larger, coarser, but hardier, slower to mature, with
inferior flesh, and a longer but coarser wool. The South Down has
always been remarkable for its power of transmitting its special
characteristics to its progeny by other kinds of sheep, and hence it
soon impressed its own characteristics on its progeny by the
Hampshire. The horns of the original breed have disappeared; the face
and legs have become dark, the frame has become more compact, the
bones smaller, the back broader and straighter, the legs shorter, and
the flesh and wool of better quality, while the superior hardiness and
greater size, as well as the large head and Roman nose of the old
breed, still remain. The Hampshires of to-day mature early and fatten
readily. They clip from six to seven pounds of wool, suitable for
combing, which is longer than South Down wool, but less fine. The
mutton has a desirable proportion of fat and lean, and is juicy and
fine flavored. The lambs are of large size and are usually dropped
early and fed for market. Indeed, the Hampshire may be considered a
larger and trifle coarser and hardier South Down. The breed is
occasionally crossed with Cotswolds, when it produces a wool more
valuable for worsted manufacturers than the pure Cotswold. Indeed,
there is little doubt that in addition to South Down, the Hampshire
has a dash of Cotswold blood in its composition. Considerable
importations of the breed have been made into this country, but it has
not become so popular as the South Down and some other English breeds.
The excellent group shown is owned by Mr. James Wood, of Mount Kisco,
New York.--_Rural New-Yorker._

       *       *       *       *       *




THE YALE COLLEGE MEASUREMENT OF THE PLEIADES.[1]

  [Footnote 1: "Determination of the Relative Positions of the
  Principal Stars in the Group of the Pleiades." By William L.
  Elkin. Transactions of the Astronomical Observatory of Yale
  University, Vol. I., Part I. (New Haven: 1887.)]


The Messrs. Repsold have established, and for the present seem likely
to maintain, a practical monopoly in the construction of heliometers.
That completed by them for the observatory of Yale College in 1882
leaves so little to be desired as to show excellence not to be the
exclusive result of competition. In mere size it does not indeed take
the highest rank. Its aperture is of only six inches, while that of
the Oxford heliometer is of seven and a half; but the perfection of
the arrangements adapting it to the twofold function of equatorial and
micrometer stamps it as a model not easy to be surpassed. Steel has
been almost exclusively used in the mounting. Recommended as the
material for the objective cell by its quality of changing volume
under variations of temperature nearly _paripassu_ with glass, its
employment was extended to the telescope tube and other portions of
the mechanism. The optical part of the work was done by Merz, Alvan
Clark having declined the responsibility of dividing the object lens.
Its segments are separable to the extent of 2°, and through the
contrivance of cylindrical slides (originally suggested by Bessel)
perfect definition is preserved in all positions, giving a range of
accurate measurement just six times that with a filar micrometer.
(Gill, "Encyc. Brit.," vol. xvi., p. 253; Fischer, _Sirius_, vol.
xvii., p. 145.)

This beautiful engine of research was in 1883 placed in the already
practiced and skillful hands of Dr. Elkin. He lost no time in fixing
upon a task suited both to test the powers of the new instrument and
to employ them to the highest advantage.

The stars of the Pleiades have, from the earliest times, attracted the
special notice of observers, whether savage or civilized. Hence, on
the one hand, their prominence in stellar mythology all over the
world; on the other, their unique interest for purposes of scientific
study and comparison. They constitute an undoubted cluster; that is to
say, they are really, and not simply in appearance, grouped together
in space, so as to fall under the sway of prevailing mutual
influences. And since there is, perhaps, no other stellar cluster so
near the sun, the chance of perceptible displacements among them in a
moderate lapse of time is greater than in any other similar case.
Authentic data regarding them, besides, have now been so long garnered
that their fruit may confidently be expected at least to begin to
ripen.

Dr. Elkin determined, accordingly, to repeat the survey of the
Pleiades executed by Bessel at Konigsberg during about twelve years
previous to 1841. Wolf and Pritchard had, it is true, been beforehand
with him; but the wide scattering of the grouped stars puts the filar
micrometer at a disadvantage in measuring them, producing minute
errors which the arduous conditions of the problem render of serious
account. The heliometer, there can be no doubt, is the special
instrument for the purpose, and it was, moreover, that employed by
Bessel; so that the Konigsberg and Yale results are comparable in a
stricter sense than any others so far obtained.

One of Bessel's fifty-three stars was omitted by Dr. Elkin as too
faint for accurate determination. He added, however, seventeen stars
from the Bonn _Durchmusterung_, so that his list comprised sixty-nine,
down to 9.2 magnitude. Two independent triangulations were executed by
him in 1884-85. For the first, four stars situated near the outskirts
of the group, and marking the angles of quadrilateral by which it was
inclosed, were chosen as reference points. The second rested upon
measures of distance and position angle outward from Alcyone ([eta]
Tauri). Thus, two wholly unconnected sets of positions were secured,
the close accordance of which testified strongly to the high quality
of the entire work. They were combined, with nearly equal weights, in
the final results. A fresh reduction of the Konigsberg observations,
necessitated by recent improvements in the value of some of the
corrections employed, was the preliminary to their comparison with
those made, after an interval of forty-five years, at Yale College.
The conclusions thus laboriously arrived at are not devoid of
significance, and appear perfectly secure, so far as they go.

It has been known for some time that the stars of the Pleiades possess
a small identical proper motion. Its direction, as ascertained by
Newcomb in 1878, is about south-southeast; its amount is somewhat less
than six seconds of arc in a century. The double star 61 Cygni, in
fact, is displaced very nearly as much in one year as Alcyone with its
train in one hundred. Nor is there much probability that this slow
secular shifting is other than apparent; since it pretty accurately
reverses the course of the sun's translation through space, it may be
presumed that the _backward_ current of movement in which the Pleiades
seem to float is purely an effect of our own _onward_ traveling.

Now the curious fact emerges from Dr. Elkin's inquiries that six of
Bessel's stars are exempt from the general drift of the group. They
are being progressively left behind. The inference is obvious that
they do not in reality belong to, but are merely accidentally
projected upon, it; or, rather, that it is projected upon them; for
their apparent immobility (which, in two of the six, may be called
absolute) shows them with tolerable certainty to be indefinitely more
remote--so remote that the path, moderately estimated at
21,000,000,000 miles in length, traversed by the solar system during
the forty-five years elapsed since the Konigsberg measures dwindles
into visual insensibility when beheld from them. The brightest of
these six far-off stars is just above the eighth (7.9) magnitude; the
others range from 8.5 down to below the ninth.

A chart of the relative displacements indicated for Bessel's stars by
the differences in their inter-mutual positions as determined at
Konigsberg and Yale accompanies the paper before us. Divergences
exceeding 0.40" (taken as the limit of probable error) are regarded as
due to real motion; and this is the case with twenty-six stars besides
the half dozen already mentioned as destined deserters from the group.
With these last may be associated two stars surmised, for an opposite
reason, to stand aloof from it. Instead of tarrying behind, they are
hurrying on in front.

An excess of the proper movement of their companions belongs to them;
and since that movement is presumably an effect of secular parallax,
we are justified in inferring their possession of an extra share of it
to signify their greater proximity to the sun. Hence, of all the stars
in the Pleiades these are the most likely to have a measurable annual
parallax. One is a star a little above the seventh magnitude,
distinguished as _s_ Pleiadum; the other, of about the eighth, is
numbered 25 in Bessel's list. Dr. Elkin has not omitted to remark that
the conjecture of their disconnection from the cluster is confirmed by
the circumstance that its typical spectrum (as shown on Prof.
Pickering's plates) is varied in _s_ by the marked character of the K
line. The spectrum of its fellow traveler (No. 25) is still
undetermined.

It is improbable, however, that even these nearer stars are
practicable subjects for the direct determination of annual parallax.
By indirect means, however, we can obtain some idea of their distance.
All that we want to know for the purpose is the _rate_ of the sun's
motion; its _direction_ we may consider as given with approximate
accuracy by Airy's investigation. Now, spectroscopic measurements of
stellar movements of approach and recession will eventually afford
ample materials from which to deduce the solar, velocity; though they
are as yet not accurate or numerous enough to found any definitive
conclusion upon. Nevertheless, M. Homann's preliminary result of
fifteen miles a second as the speed with which our system travels in
its vast orbit inspires confidence both from the trustworthiness of
the determinations (Mr. Seabroke's) serving as its basis and from its
intrinsic probability. Accepting it provisionally, we find the
parallax of Alcyone = about 0.02', implying a distance of
954,000,000,000,000 miles and a light journey of 163 years. It is
assumed that the whole of its proper motion of 2.61' in forty-five
years is the visual projection of oar own movement toward a point in
R.A. 261°, Decl. +25°.

Thus the parallax of the two stars which we suspect to lie between us
and the stars forming the genuine group of the Pleiades, at perhaps
two-thirds of their distance, can hardly exceed 0.03'. This is just
half that found by Dr. Gill for [xi] Toucani, which may be regarded
as, up to this, the smallest annual displacement at all satisfactorily
determined. And the error of the present estimate is more likely to be
on the side of excess than of defect. That is, the stars in question
can hardly be much nearer to us than is implied by an annual parallax
of 0.03", and they may be considerably more remote.

Dr. Elkin concludes, from the minuteness of the detected changes of
position among the Pleiades, that "the hopes of obtaining any clew to
the internal mechanism of this cluster seem not likely to be realized
in an immediate future;" remarking further: "The bright stars in
especial seem to form an almost rigid system, as for only one is there
really much evidence of motion, and in this case the total amount is
barely 1 per century." This one mobile member of the naked eye group
is Electra; and it is noticeable that the apparent direction of its
displacement favors the hypothesis of leisurely orbital circulation
round the leading star. The larger movements, however, ascribed to
some of the fainter associated stars are far from harmonizing with
this preconceived notion of what they ought to be.

On the contrary, so far as they are known at present, they force upon
our minds the idea that the cluster may be undergoing some slow
process of disintegration. M. Wolf's impression of incipient
centrifugal tendencies among its components certainly derives some
confirmation from Dr. Elkin's chart. Divergent movements are the most
strongly marked; and the region round Alcyone suggests, at the first
glance, rather a very confused area of radiation for a flight of
meteors than the central seat of attraction of a revolving throng of
suns.

There are many signs, however, that adjacent stars in the cluster do
not pursue independent courses. "Community of drift" is visible in
many distinct sets; while there is as yet no perceptible evidence,
from orbital motion, of association into subordinate systems. The
three eighth-magnitude stars, for instance, arranged in a small
isosceles triangle near Alcyone, do not, as might have been expected
_a priori_, constitute a real ternary group. They are all apparently
traveling directly away from the large star close by them, in straight
lines which may, of course, be the projections of closed curves; but
their rates of travel are so different as to involve certain
progressive separation. Obviously, the order and method of such
movements as are just beginning to develop to our apprehension among
the Pleiades will not prove easy to divine.--_A.M. Clerke, in Nature._

       *       *       *       *       *




DEEP SEA DREDGINGS: EXAMINATION OF SEA BOTTOMS.

By THOMAS T.P. BRUCE WARREN.


I believe Prof. Ehrenberg was one of the first to examine,
microscopically, deep sea dredgings, some of which were undertaken for
the Atlantic cable expedition, 1857.

I propose to deal with the bottoms brought up from tropical waters of
the Atlantic, a few years ago, during certain telegraph cable
operations. These soundings were made for survey purposes, and not for
any biological or chemical investigations. Still I think that this
imperfect record may be a useful contribution to chemical science,
bearing especially on marine operations.

Although there is little to be added to the chemistry of this subject,
still I think there are few chemists who could successfully make an
analysis of a deep sea "bottom" without some sacrifice of time and
patience, to say nothing of the risk of wasting a valuable specimen.

The muds, clays, oozes, etc., from deep water are so very fine that
they pass readily through the best kinds of filters, and it is
necessary to wash out all traces of sea water as a preliminary. The
specimen must be _repeatedly_ washed by decantation, until the
washings are perfectly free from chlorine, when the whole may be
thrown onto a filter _merely_ to drain. The turbid water which passes
through is allowed to stand so that the suspended matter may settle,
and after decanting the clear supernatant water, the residuum is again
thrown on to the filter.

The washing and getting ready for the drying oven will, in some cases,
require days to carry out, if we wish to avoid losing anything.

So far the proceeding is exactly the same, except draining on a
filter, which would be adopted for preparing for the microscope. On no
account should the opportunity be missed of mounting several slides
permanently for microscopic examination. Drawings or photographic
enlargements will render us independent of direct microscopic appeal,
which is not at all times convenient.

The substance, if drained and allowed to dry on the filter, will
adhere most tenaciously to it, so that it is better to complete the
drying in a porcelain or platinum capsule, either by swilling the
filter with a jet of water or by carefully removing with a spatula.
The most strenuous care must be used not to contaminate the specimen
with loose fibers from the filter.

The perfectly dried matter is best treated in exactly the same way as a
residuum in water analysis. It is a common thing to ignite the residuum,
and to put the loss down, if any, to water. This ought not to satisfy an
accurate observer, since organic matter, carbonates--especially in
presence of silica--will easily add to the loss. The best plan is to
heat a small portion very cautiously, and note if any smell or
alteration in color, due to carbon, etc., is perceptible, and to proceed
accordingly.

I have seen some very satisfactory analyses made on board ship by a
skillful use of the blowpipe, where liquid reagents would be very
inconvenient to employ.

It will be necessary to say a few words as to the way in which
soundings are made at sea. When the bottom consists of sand, mud, or
other loose matter, it is easy enough to bring specimens to the
surface, and, of course, we know in such a case that the bottom has
been reached, but, in the event of the bottom being hard and rocky, it
is not easy to say that our sounding has been successful: and here we
meet with a difficulty which unfortunately is most unsatisfactorily
provided for.

The lead is "cast," as the saying goes, "armed" for this emergency. An
iron sinker is made with a hollow recess in the bottom; this is filled
in with tallow, and on striking the bottom any loose matter may adhere
by being pressed into the tallow. If the bottom is rocky or hard we
get simply an imprint in the arming, and when such a result is
obtained the usual construction is that "the bottom is rocky" or hard.

Now, this seems to me a point on which chemistry may give some very
valuable help, for I am convinced that no sounding should be accepted
unless evidence of the bottom itself is obtained. A few considerations
will show that when we are working in very deep water, where there is
a difficulty of knowing for certain that we have an "up and down"
sounding, and the hardening of the "arming" by the cold and pressure,
unless we bring up something we cannot be sure that we have touched
the bottom; leaving the doubt on this point on one side, unless we use
a very heavy sinker, so as to get an indication of the released strain
when it touches the bottom, we encounter another complication.

Sir William Thomson's sounding wire has added the element of
reliability to our soundings in this latter case. The note given out
by the wire when the bottom is reached is perceptibly different when
under strain, even if the dynamometer should give an unreliable
indication.

It has been found that when a "bottom" has been recovered by the
arming with tallow, the adherent grease seriously detracts from the
value of the specimen for scientific purposes. Washing with perfectly
pure bisulphide carbon will save the sounding, but of course any
living organism is destroyed. As we have plenty of contrivances for
bringing up loose "bottoms" without arming, we have nothing to fear on
this score.

There is a great difficulty to explain the vast accumulations of clay
deposits on the ocean bed, and it has been suggested that some minute
organisms may produce these deposits, as others give us carbonate of
lime. Is there not a very great probability of some of the apparently
insoluble rocky formations being answerable for these accumulations?

We must not forget the peculiar changes which such an apparently
stable substance as feldspar undergoes when disintegrated and exposed
to the chemical action of sea water. As these deposits contain both
sodium and potassium, our chemical operations must provide for the
analytical results; in other respects the analysis can be proceeded
with according to the operator's analytical knowledge.

Few operators are aware of the usefulness of an ordinary deep sea
grapnel rope, as used for cable work, in recovering specimens of the
fauna of any locality. The grapnel rope should be left down for a few
months, so that the denizens of the deep may get used to it and make
it their place of residence and _attachment_. The stench caused by
their decomposition, unless the rope be kept in water, when hauled up
will be in a few days intolerable, even to an individual with a
sea-going stomach. I tried several chemical solutions for preserving
specimens thus recovered, but nothing answered so well as the water
itself drawn up from the same depth as the rope was recovered
from.--_Chem. News._

       *       *       *       *       *


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