Scientific American Supplement, No. 288 by Various

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Olaf Voss, Don Kretz, Juliet Sutherland, Charles Franks
and the Online Distributed Proofreading Team.

[Illustration]

SCIENTIFIC AMERICAN SUPPLEMENT NO. 288

NEW YORK, JULY 9, 1881

Scientific American Supplement. Vol. XI, No. 288.

Scientific American established 1845

Scientific American Supplement, $5 a year.

Scientific American and Supplement, $7 a year.

* * * * *

TABLE OF CONTENTS.

I. ENGINEERING AND MECHANICS--Dry Air Refrigerating Machine.
5 figures. Plan, elevation, and diagrams of a new English
dry air refrigerator

Thomas' Improved Steam Wheel. 1 figure

The American Society of Civil Engineers. Address of President
Francis, at the Thirteenth Annual Convention, at Montreal. The
Water Power of the United States, and its Utilization

II. TECHNOLOGY AND CHEMISTRY.--Alcohol in Nature. Its presence
in earth, atmosphere, and water. 6 figures. Distillatory apparatus
and (magnified) iodoform crystals from snow water, from
rain water, from vegetable mould, etc.

Detection of Alcohol in Transparent Soaps. By H. JAY

On the Calorific Power of Fuel, and on Thompson's Calorimeter.
By J.W. THOMAS

Explosion as an Unknown Fire Hazard. A suggestive review of
the conditions of explosions, with curious examples

Carbon. Symbol C. Combining weight. 12. By T. A. POOLEY
Second article on elementary chemistry written for brewers

Manufacture of Soaps and their Production. By W. J. MENZIES

The Preparation of Perfume Pomades. 1 figure. "Ensoufflage"
apparatus for perfumes

Organic Matter in Sea Water

Bacteria Life. Influence of heat and various gases and chemical
compounds on bacteria life

On the Composition of Elephant's Milk. By Dr. CHAS. A. DOREMUS.
Comparison of elephant's milk with that of ten other mammals

The Chemical Composition of Rice. Maize, and Barley. By J. STEINER

Petroleum Oils. Character and properties of the various distillates
of crude petroleum. Fire risks attending the use of the
lighter petroleum oils

Composition of the Petroleum of the Caucasus. By P. SCHULZENBERGER
and N. TONINE

Notes on Cananga Oil. or Ilang-Ilang Oil. By F. A. FLÜCKIGER.
1 figure. Flower and leaf of Cananga odorata

Chian Turpentine, and the Tree which Produces It. By Dr.
STIEPOWICH. of Chios, Turkey

On the Change of Volume which Accompanies the Galvanic Deposition
of a Metal. By M. E. BOUTY

Analysis of the Rice Soils of Burmah. By R. ROMANIC, Chemical
Examiner, British Burmah

III. PHYSICS AND PHYSICAL APPARATUS.--Seyfferth's Pyrometer.
7 figures.--Pyrometer with electric indicator.--Method of
mounting by means of a cone on vacuum apparatus.--Mounting by
means of a sleeve.--Mounting by means of a thread on a tube.--
Mounting by means of a clasp in reservoirs.--The pyrometer
mounted on a bone-black furnace.--Mounted on a brick furnace

Delicate Scientific Instruments. By EDGAR L. LARKIN. An
interesting description of the more powerful and delicate
instruments of research used by modern scientists and their
marvelous results

The Future Development of Electrical Appliances. Lecture by
Prof. J. W. PERRY before the London Society of Arts.--Methods
and units of electrical measurements

Researches on the Radiant Matter of Crookes and the Mechanical
Theory of Electricity. By Dr. W. F. GINTL

Economy of the Electric Light. W. H. PREECE'S Experiments
Investigations

On the Space Protected by a Lightning Conductor. By WM. H.
PREECE.--5 figures

Photo-Electricity of Fluor Spar Crystals

The Aurora Borealis and Telegraph Cables

The Photographic Image: What It Is. By T. H. MORTON.
1 figure.--Section of sensitive plate after exposure and during
development

Gelatine Transparencies for the Lantern

An Integrating Machine. By C. V. BOYS.--1 figure

Upon a Modification of Wheatstone's Microphone and its
Applicability to Radiophonic Researches.
By ALEX. GRAHAM BELL,--2 figures

IV. ARCHITECTURE.--Suggestions in Architecture, 1 figure.--A
pair of English cottages. By A. CAWSTON

* * * * *

ALCOHOL IN NATURE--ITS PRESENCE IN THE EARTH, WATER, AND ATMOSPHERE.

A Chemist of merit, Mr. A. Müntz, who has already made himself known by
important labors and by analytical researches of great precision, has
been led to a very curious and totally unexpected discovery, on the
subject of which he has kindly given us information in detail, which we
place before our readers.[1] Mr. Müntz has discovered that arable soil,
waters of the ocean and streams, and the atmosphere contain traces of
alcohol; and that this compound, formed by the fermentation of organic
matters, is everywhere distributed throughout nature. We should add that
only infinitesimal quantities are involved--reaching only the proportion
of millionths--yet the fact, for all that, offers a no less powerful
interest. The method of analysis which has permitted the facts to be
shown is very elegant and scrupulously exact, and is worthy of being
made known.

[Footnote 1: The accompanying engravings have been made from drawings of
the apparatus in the laboratory of which Mr. Müntz is director, at the
Agronomic Institute.]

[Illustration: FIG. 1.--FIRST DISTILLATORY APPARATUS.]

[Illustration: FIG. 2.--SECOND DISTILLATORY APPARATUS.]

Mr. Müntz's method of procedure is as follows: He submits to
distillation three or four gallons of snow, rain, or sea water in an
apparatus such as shown in Fig. 1. The part which serves as a boiler,
and which holds the liquid to be distilled, is a milk-can, B. The vapors
given off through the action of the heat circulate through a leaden tube
some thirty-three feet in length, and then traverse a tube inclosed
within a refrigerating cylinder, T, which is kept constantly cold by a
current of water. They are finally condensed in a glass flask, R, which
forms the receiver. When 100 or 150 cubic centimeters of condensed
liquid (which contains all the alcohol) are collected in the receiver,
the operations are suspended. The liquid thus obtained is distilled anew
in a second apparatus, which is analogous to the preceding but much
smaller (Fig. 2). The liquid is heated in the flask, B, and its vapor,
after traversing a glass worm, is condensed in the tube, T. The
operation is suspended as soon as five or six cubic centimeters of the
condensed liquid have been collected in the test-tube, R. The latter is
now removed, and to its liquid contents, there is added a small quantity
of iodine and carbonate of soda. The mixture is slightly heated, and
soon there are seen forming, through precipitation, small crystals of
iodoform. Under such circumstances, iodoform could only have been formed
through the presence of an alcohol in the liquid. These analytical
operations are verified by Mr. Müntz as follows: He distills in the same
apparatus three to four gallons of chemically pure distilled water, and
ascertains positively that under these conditions iodine and carbonate
of soda give absolutely no reaction. Finally, to complete the
demonstration and to ascertain the approximate quantity of alcohol
contained in natural waters, he undertakes the double fractional
distillation of a certain quantity of pure water to which he has
previously added a one-millionth part of alcohol. Under these
circumstances the iodine and carbonate of soda give a precipitate of
iodoform exactly similar to that obtained by treating natural waters.

[Illustration: Fig. 3.--IODOFORM CRYSTALS OBTAINED DIRECTLY (greatly
magnified).]

[Illustration: FIG. 4,--IODOFORM CRYSTALS OBTAINED WITH RAIN WATER.]

In the case of arable soil, Mr. Müntz stirs up a weighed quantity of the
material to be analyzed in a certain proportion of water, distills it in
the smaller of the two apparatus, and detects the alcohol by means of
the same operation as before.

[Illustration: FIG. 5.--IODOFORM CRYSTALS OBTAINED WITH SNOW WATER.]

The formation of iodoform by precipitation under the action of iodine
and carbonate of soda is a very sensitive test for alcohol. Iodoform
has sharply defined characters which allow of its being very easily
distinguished. Its crystalline form, especially, is entirely typical,
its color is pale yellowish, and, when it is examined under the
microscope, it is seen to be in the form of six-pointed stars precisely
like the crystalline form of snow. Mr. Müntz has not been contented to
merely submit the iodoform precipitates obtained by him to microscopical
examination, but has preserved the aspect of his preparations by
means of micro-photography. The figures annexed show some of the most
characteristic of the proofs. Fig. 1 shows crystals of iodoform obtained
with pure water to which one-millionth part of alcohol had been added.
Fig. 2 exhibits the form of the crystals obtained with rain water; and
Fig. 3, those with water. Fig. 4 shows crystals obtained with arable
soil or garden mould. The first of Mr. Müntz's experiments were made
about four years ago; but since that time he has treated a great number
of rain and snow waters collected both at Paris and in the country. At
every distillation all the apparatus was cleansed by prolonged washing
in a current of steam; and, in order to confirm each analysis, a
corresponding experiment was made like the one before mentioned. More
than eighty trials gave results which were exactly identical. The
quantity of alcohol contained in rain, snow, and sea waters may be
estimated at from one to several millionths. Cold water and melted snow
seem to contain larger proportions of it than tepid waters. In the
waters of the Seine it is found in appreciable quantities, and in sewage
waters the proportions increase very perceptibly. Vegetable mould is
quite rich in it; indeed it is quite likely that alcohol in its natural
state has its origin in the soil through the fermentation of the organic
matters contained therein. It is afterward disseminated throughout the
atmosphere in the state of vapor and becomes combined with the aqueous
vapors whenever they become condensed. The results which we have just
recorded are, as far as known to us, absolutely new; they constitute a
work which is entirely original, which very happily goes to complete the
history of the composition of the soil and atmosphere, and which does
great credit to its author.--_La Nature_.

[Illustration: FIG. 6.--IODOFORM CRYSTALS OBTAINED WITH VEGETABLE
MOULD.]

* * * * *

DETECTION OF ALCOHOL IN TRANSPARENT SOAPS.

By H. JAY.

It appears that every article manufactured with the aid of alcohol is
required on its introduction into France to pay duty on the supposed
quantity of this reagent which has been used in its preparation. Certain
transparent soaps of German origin are now met with, made, as is
alleged, without alcohol, and the author proposes the following process
for verifying this statement by ascertaining--the presence or absence of
alcohol in the manufactured article: 50 grms. of soap are cut into
very small pieces and placed in a phial of 200 c.c. capacity; 30 grms.
sulphuric acid are then added, and the phial is stoppered and agitated
till the soap is entirely dissolved. The phial is then filled up with
water, and the fatty acids are allowed to collect and solidify. The
subnatant liquid is drawn off, neutralized, and distilled. The first 25
c.c. are collected, filtered, and mixed, according to the process of MM.
Riche and Bardy for the detection of alcohol in commercial methylenes,
with ½ c.c. sulphuric acid at 18° B., then with the same volume of
permanganate (15 grms. per liter), and allowed to stand for one minute.
He then adds 8 drops of sodium hyposulphite at 33° B., and 1 c.c. of a
solution of magenta, 1 decigrm. per liter. If any alcohol is present
there appears within five minutes a distinct violet tinge. The presence
of essential oils gives rise to a partial reduction of the permanganate
without affecting the conversion of alcohol into aldehyd.

* * * * *

ON THE CALORIFIC POWER OF FUEL, AND ON THOMPSON'S CALORIMETER.

By J.W. THOMAS, F.C.S., F.I.C.

A simple experiment, capable of yielding results which shall be at least
comparative, has long been sought after by large consumers of coal and
artificial fuel abroad in order to ascertain the relative calorific
power possessed by each description, as it is well known that the
proportion of mineral matter and the chemical composition of coal differ
widely. The determination of the ash in coal is not a highly scientific
operation; hence it is not surprising that foreign merchants should
have become alive to the importance of estimating its quantity. While,
however, the nature and quantity of the ash can be determined without
much difficulty, the determination of the chemical composition of
coal entails considerable labor and skill; hence a method giving the
calorific power of any fuel in an exact and reliable manner by a simple
experiment is a great desideratum. This will become more obvious when
one takes into consideration the many qualities and variable characters
of the coals yielded by the South Wales and North of England coal
fields. Bituminous coals--giving some 65 per cent, of coke--are
preferred for some manufacturing purposes and in some markets.
Bituminous steam coals, yielding 75 per cent, of coke, are highly prized
in others. Semi-bituminous steam coals, yielding 80 to 83 per cent, of
coke, are most highly valued, and find the readiest sale abroad; and
anthracite steam coal (dry coals), giving from 85 to 88 per cent, of
coke (using the term "coke" as equivalent to the non-volatile portion of
the coal) is also exported in considerable quantity. Now the estimation
of the ash of any of these varieties of coal would afford no evidence
as to the class to which that coal belongs, and there is no simple test
that will give the calorific power of a coal, and at the same time
indicate the degree of bituminous or anthracitic character which it
possesses.

In order to obtain such information it is necessary that the percentage
of coke be determined together with the sulphur, ash, and water, and
these form data which at once show the nature of a fuel and give some
indication of its value. To ascertain the quantity of the sulphur, ash,
and water with accuracy involves more skill and aptitude than can
be bestowed by the non-professional public; the consequence is that
experiments entailing less time and precision, like those devised by
Berthier and Thompson, have been tried more or less extensively.
In France and Italy, Berthier's method--slightly modified in some
instances--has been long used. It is as follows:

70 grammes of oxide of lead (litharge) and 10 grammes of oxychloride of
lead are employed to afford oxygen for the combustion of 1 gramme of
fuel in a crucible. From the weight of the button of lead, and taking
8,080 units as the equivalent of carbon, the total heat-units of the
fuel is calculated. This experiment is very imperfect and erroneous upon
scientific grounds, since the hydrogen of the fuel is scarcely taken
into account at all. In the first place, hydrogen consumes only one
quarter as much oxygen as carbon, and, furthermore, two-ninths only of
the heating power of hydrogen is used as the multiplying number,
viz., 8,080, while the value of hydrogen is 34,462. In other words,
one-eighteenth only of the available hydrogen present in the fuel is
shown in the result obtained. Apart from this my experience of the
working of Berthier's method has been by no means satisfactory. There
is considerable difficulty in obtaining pure litharge, and it is almost
impossible to procure a crucible which does not exert a reducing action
upon the lead oxide. Some twelve months ago I went out to Italy to test
a large number of cargoes of coal with Thompson's calorimeter, and since
then this apparatus has superseded Berthier's process, and is likely to
come into more general use. Like Berthier's method, Thompson's apparatus
is not without its disadvantages, and the purpose of this paper is to
set these forth, as well as to suggest a uniform method of working by
means of which the great and irreconcilable differences in the results
obtained by some chemists might be overcome. It has already been
observed that a coal rich in hydrogen shows a low heating power by
Berthier's method, and it will become evident on further reflection that
the higher the percentage of carbon the greater will be the indicated
calorific power. In fact a good sample of anthracite will give higher
results than any other class of coal by Berthier's process. With
Thompson's calorimeter the reverse is the case, as the whole of the
heating power of the hydrogen is taken into account. In short, with
careful working, the more bituminous a coal is the more certain is it
that its full heating power shall be exerted and recorded, so far as the
apparatus is capable of indicating it; for when the result obtained is
multiplied by the equivalent of the latent heat of steam the product is
always below the theoretical heat units calculated from the chemical
composition of the coal by the acid of Favre and Silbermann's figures
for carbon and hydrogen. On the other hand, when the heating power of
coal low in hydrogen is determined by Thompson's calorimeter, much
difficulty is experienced in burning the carbon completely; hence a low
result is obtained. From a large number of experiments I have found that
when a coal does not yield more than 86 per cent, of coke, it gives its
full comparative heating power, but it is very questionable if equal
results will be worked out if the coke exceeds the above amount although
I have met with coals giving 87 per cent. of coke which were perfectly
manageable, though in other cases the coal did not burn completely. It
will be noted that the non-volatile residue of anthracite is never as
low as 86 per cent., and this, together with the very dry steam coals
and bastard anthracite (found over a not inextensive tract of the South
Wales Coal field), form a series of coals, alike difficult to burn in
Thompson's calorimeter. Considerable experience has shown that in no
single instance was the true comparative heating power of anthracite
or bastard anthracite indicated. With a view to accelerate the perfect
combustion of these coals, sugar, starch, bitumen, and bituminous
coals--substances rich in hydrogen--were employed, mixed in varying
proportions with the anthracitic coal, but without the anticipated
effect. Coke was also treated in a like manner. Without enlarging
further upon these futile trials--all carefully and repeatedly
verified--the results of my experiments and experience show that for
coals of an anthracitic character, yielding more than 87 per cent. of
coke, or for coke itself, Thompson's calorimeter is not suited as an
indicator of their comparative calorific power, for the simple reason
that some of the carbon is so graphitic in its nature that it will not
burn perfectly when mixed with nitrate and chlorate of potash. A sample
of very pure anthracite used in the experiments referred to, gave 90.4
per cent. of non-volatile residue, and only 0.84 per cent. of ash. This
coal was not difficult to experiment with, as combustion started with
comparative ease and proceeded quite rapidly enough, but in every
instance a portion of the carbon was unconsumed, and consequently
instead of about 13° of rise in temperature only 10° were recorded.

Since the calorific power of a coal is determined by the number of
degrees Fahrenheit which a given quantity of water is raised in
temperature by a known weight of fuel, it follows that every care should
be taken that the experiment be performed under similar atmospheric
conditions. The oscillation of barometric pressure does not appear to
affect the working, but the temperature of the room in which the
work was done, and especially that of the water, are most important
considerations. It has been observed by some who have used this
apparatus--and I have frequently noticed it myself--that the lower the
temperature of the water is under which the fuel is burnt the higher is
the result found. This has been explained on the assumption that the
colder the water used, the greater is the difference between the
temperature of the room and that of the water; hence it would be
expedient that in all cases when such experiments are made the same
difference of temperature between the air in the room and the water
employed should always exist. For example, if the temperature of the
room were 70°, and the water at 60°, then the same coal would give a
like result with the water at 40° and the room at 50°. This has been
regarded as the more evident, because the gases passing through
the water escape under favorable conditions of working at the same
temperature as the water, and are perfectly deprived of any heat in
excess of that possessed by the water. Under these circumstances it
would seem only reasonable that this assumption should be correct. It
was, however, found after a large number of experiments upon the same
sample of coal that this was not the case. 30 grammes of coal which
raises the temperature of the water 13.4°, when the water at starting
was 60° and the room at 70°, gives 13.7° rise of temperature with the
water at 40° and the room at 50°. Conversely, when the water is at 70°
and the room at 80°, a lower result is obtained. The explanation appears
to be this: The gas which escapes from the water was not in existence in
the gaseous form previous to the experiment, and the heat communicated
to the gas being a definite quantity it follows that the more the gas
is cooled the greater the proportion of chemical energy in the shape of
heat will be utilized and recorded as calorific power.

In order, therefore, to make the experiment more simple and workable
at all temperatures, a sample of coal was selected, which should be
perfectly manageable and readily consumed. Appended is an analysis of
the coal employed (from Ebbw Vale, Monmouthshire):

Composition per cent.

Carbon...............................88.33
Hydrogen............................. 5.08
Oxygen............................... 3.28
Nitrogen............................. 0.55
Sulphur.............................. 0.70
Ash.................................. 1.26
Water (moisture)..................... 0.80
-----
100.00

In the following experiments the standard temperature of the water was
taken as 60° F., and as the coal gave 13.4° of rise of temperature, 67°
F. was selected as the standard room temperature. The reason for this
room temperature is obvious, for, whatever heating effect the higher
temperature of the room may have upon the water in the cylinder during
the time occupied by the first half of the experiment, would be
compensated for by the loss sustained during the second half of the
experiment, when the temperature of the water exceeded that of the room.
The mean of numerous trials gave 13.4° F. rise of temperature, equal to
14.74 lb. of water per lb. of coal. When the water was at 50° and
the room at 57°, the mean of several experiments gave 13.5° rise of
temperature. When the water was 40° at starting and the room at 47°,
13.65° was the average rise of temperature. Trials were made at
intermediate temperatures, and the results always showed that higher
figures were recorded when the water was coldest. With a view of getting
uniformity in the results it was thought well to make experiments, in
order to find out what temperature the room should be at, so that this
coal might give the same result with the water at 50°, 40°, or at
intermediate temperatures. Without going much into detail, it was found
that when the temperature of the room was at 40° and that of the water
40°, and the experiment was rapidly and carefully performed, 13.4° rise
of temperature was given; but this result could be obtained without
special effort when the room was 42° and the water 40° at starting. It
is evident that the cooling effect of the air in the room upon the water
cylinder is very appreciable when the water has reached 13° above that
of the room. When the water was at 50° and the room at 55°, the coal
gave 13.4° rise with ease and certainty, and it would not be out of
place to remark here that with those coals which burn well in Thompson's
calorimeter, the results of several trials are remarkably uniform when
properly performed. With the water at 70° and the room at 80°, a like
result was worked out. Experiments at intermediate temperatures were
also carried out (see table in sequel). It is true that the whole
difference of temperature we are dealing with in making these
corrections is only 0.25, but 0.2 in the result, when multiplied by 537
to bring it into calories, as is done by the authorities in Italy, makes
more than 100 heat units--a serious difference when 5d. per ton fine is
attached to every 100 calories lower than the number guaranteed.

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