Thomas Jefferson - "Memoir, Correspondence, And Miscellanies, From The Papers Of Thomas Jefferson"

Various - "International Conference Held at Washington for the Purpose of Fixing a Prime Meridian and a Universal Day. October, 1884."

Henry Beam Piper - "Murder in the Gunroom"

Jacob Abbott - "King Alfred of England"

Various - Scientific American Supplement, No. 421, January 26, 1884

V >> Various >> Scientific American Supplement, No. 421, January 26, 1884



[Illustration]




SCIENTIFIC AMERICAN SUPPLEMENT NO. 421




NEW YORK, JANUARY 26, 1884

Scientific American Supplement. Vol. XVII., No. 421.

Scientific American established 1845

Scientific American Supplement, $5 a year.

Scientific American and Supplement, $7 a year.


* * * * *




TABLE OF CONTENTS


I. ENGINEERING AND MECHANICS.--Furcot's Six Horse Power
Steam Engine.--With several figures. 6714

Foot Lathes.--With engraving. 6715

Endless Trough Conveyer.--2 engravings. 6715

Railroad Grades of Trunk Lines. 6715

English Express Trains.--Average speed, long runs, etc. 6715

Apparatus for Separating Substances Contained in the
Waste Waters of Paper Mills, etc.--2 figures. 6717

II. TECHNOLOGY.--An English Adaptation of the American Oil
Mill.--Description of the apparatus, and of the old and
new processes.--Several engravings. 6716

Large Blue Prints.--By W.B. Parsons, Jr. 6717

III. ELECTRICITY, ETC.--Electrical Apparatus for Measuring
and for Demonstration at the Munich Exhibition.--With
descriptions and numerous illustrations of the different
machines. 6711

A New Oxide of Copper Battery.--By F. De Lalande and S.
Chaperon.--With description and three illustrations. 6714

IV. MATHEMATICS, ETC.--To Find the Time of Twilight.--1 figure. 6720

A New Rule for Division in Arithmetic. 6725

Experiments in Binary Arithmetic. 6726

V. ARCHAEOLOGY.--Grecian Antiquities.--With engravings of the
Monument of Philopappus.--Tomb from the Ceramicus.--Tower
of the winds.--The Acropolis.--Old Corinth.--Temple of
Jupiter.--The Parthenon.--Temple of Theseus, etc. 6721

VI. NATURAL HISTORY, ETHNOLOGY, ETC.--Poisonous Serpents and
their Venom.--By Dr. Archie Stockwell.--A serpent's mouth,
fangs, and poison gland.--Manner of attack.--Nature of
the venom.--Action of venom.--Remedies. 6719

Ethnological Notes.--Papuans.--Negritos. 6720

VII. HORTICULTURE, BOTANY, ETC.--The Hornbeams.--Uses to
which the tree is put.--Wood for manufactures.--For
fuel.--Different varieties.--With engravings of the tree
as a whole, and of its leaves, fruit, flowers, etc. 6724

Fruit of Camellia Japonica.--1 engraving. 6725

VIII. MEDICINE. SANITATION, ETC.--House Drainage and Refuse.
Abstract of a lecture by Capt. Douglas Galton.--Treating
of the removal of the refuse from camps, small towns, and
houses.--Conditions to observe in house drains, etc. 6717

Pasteur's New Method of Attenuation. 6718

Convenient Vaults. 6719

IX. MISCELLANEOUS.--Spanish Fisheries.--Noticeable objects
in the Spanish Court at the late Fisheries Exhibition. 6722

Duck Shooting at Montauk. 6723

* * * * *




ELECTRICAL APPARATUS FOR MEASURING AND FOR DEMONSTRATION AT THE MUNICH
EXHIBITION.


Apparatus for use in laboratories and cabinets of physics were quite
numerous at the Munich Exhibition of Electricity, and very naturally a
large number was to be seen there that presented little difference
with present models. Several of them, however, merit citation. Among
the galvanometers, we remarked an apparatus that was exhibited by
Prof. Zenger, of Prague. The construction of this reminded us of that
of other galvanometers, but it was interesting in that its inventor
had combined in it a series of arrangements that permitted of varying
its sensitiveness within very wide limits. This apparatus, which Prof.
Zenger calls a "Universal Rheometer" (Fig. 1), consists of a bobbin
whose interior is formed of a piece of copper, whose edges do not
meet, and which is connected by strips of copper with two terminals.
This internal shell is capable of serving for currents of quantity,
and, when the two terminals are united by a wire, it may serve as a
deadener. Above this copper shell there are two identical coils of
wire which may, according to circumstances, be coupled in tension or
in series, or be employed differentially. Reading is performed either
by the aid of a needle moving over a dial, or by means of a mirror,
which is not shown in the figure. Finally, there is a lateral scale,
R, which carries a magnetized bar, A, that may be slid toward the
galvanometer. This magnet is capable of rendering the needle less
sensitive or of making it astatic. In order to facilitate this
operation, the magnet carries at its extremity a tube which contains a
bar of soft iron that may be moved slightly so as to vary the length
of the magnet. Prof. Zenger calls this arrangement a magnetic vernier.
It will be seen that, upon combining all the elements of the
apparatus, we can obtain very different combinations; and, according
to the inventor, his rheometer is a substitute for a dozen
galvanometers of various degrees of sensitiveness, and permits of
measuring currents of from 20 amperes down to 1/50000000 an ampere.
The apparatus may even be employed for measuring magnetic forces, as
it constitutes a very sensitive magnetometer.

[Illustration: FIG. 1.--ZENGER'S UNIVERSAL RHEOMETER.]

Prof. Zenger likewise had on exhibition a "Universal Electrometer"
(Fig. 2), in which the fine wire that served as an electrometric
needle was of magnetized steel suspended by a cotton thread. In this
instrument, a silver wire, t, terminating in a ball, is fixed to a
support, C, hanging from a brass disk, P, placed upon the glass case
of the apparatus. It will be seen that if we bring an electrified body
near the disk, P, a deviation of the needle will occur. The
sensitiveness of the latter may be regulated by a magnetic system like
that of the galvanometer. Finally, a disk, P', which may be slid up
and down its support, permits of the instrument being used as a
condensing electrometer, by giving it, according to the distance of
the disks, different degrees of sensitiveness. One constructor who
furnished much to this part of the exhibition was Mr. Th. Edelmann of
Munich, whose apparatus are represented in a group in Fig. 3. Among
them we remark the following: A quadrant electrometer (Fig. 4), in
which the horizontal 8-shaped needle is replaced by two connected
cylindrical surfaces that move in a cylinder formed of four parts; a
Von Beetz commutator; spyglasses with scale for reading measuring
instruments (Fig. 3); apparatus for the study of magnetic variations,
of Lamont (Fig. 3) and of Wild (Fig. 5); different types of the
Wiedemann galvanometer; an electrometer for atmospheric observations
(Fig. 6); a dropping apparatus (Fig. 7), in which the iron ball opens
one current at a time at the moment it leaves the electro-magnet and
when it reaches the foot of the support, these two breakages producing
two induction sparks that exactly limit the length to be taken in
order to measure the time upon the tracing of the chronoscope
tuning-fork; an absolute galvanometer; a bifilar galvanometer (Fig. 8)
for absolute measurements, in which the helix is carried by two
vertical steel wires stretched from o to u, and which is rendered
complete by a mirror for the reading, and a second and fixed helix, so
that an electro-dynamometer may be made of it; and, finally, a
galvanometer for strong currents, having a horseshoe magnet pivoted
upon a vertically divided column which is traversed by the current,
and a plug that may be arranged at different heights between the two
parts of the column so as to render the apparatus more sensitive (Fig.
9).

[Illustration: FIG. 2.--ZENGER'S UNIVERSAL ELECTROMETER.]

We may likewise cite the exhibit of Mr. Eugene Hartmann of Wurtzburg,
which comprised a series of apparatus of the same class as those that
we have just enumerated--spyglasses for the reading of apparatus,
galvanometers, magnetometers, etc.

[Illustration: FIG. 3.--EXHIBIT OF TH. EDELMANN.]

Specially worthy of remark were the apparatus of Mr. Kohlrausch for
measuring resistances by means of induction currents, and a whole
series of accessory instruments.

Among the objects shown by other exhibitors must be mentioned Prof.
Von Waltenhofen's differential electromagnetic balance. In this, two
iron cylinders are suspended from the extremities of a balance. One of
them is of solid iron, and the other is of thin sheet iron and of
larger diameter and is balanced by an additional weight. Both of them
enter, up to their center, two solenoids. If a strong current be
passed into these latter, the solid cylinder will be attracted; but
if, on the contrary, the current be weak, the hollow cylinder will be
attracted. If the change in the current's intensity occur gradually,
there will be a moment in which the cylinders will remain in
equilibrium.

[Illustration: FIG. 4.--EDELMANN'S QUADRANT ELECTROMETER.]

Prof. Zenger's differential photometer that we shall finally cite is
an improvement upon Bunsen's. In the latter the position of the
observer's eye not being fixed, the aspect of the spot changes
accordingly, and errors are liable to result therefrom. Besides,
because of the non-parallelism of the luminous rays, each of the two
surfaces is not lighted equally, and hence again there may occur
divergences. In order to avoid such inconveniences, Prof. Zenger gives
his apparatus (Fig. 10) the following form: The screen, D, is
contained in a cubical box capable of receiving, through apertures,
light from sources placed upon the two rules, R and R'. A flaring
tube, P, fixes the position of the eye very definitely. As for the
screen, this is painted with black varnish, and three vertical
windows, about an inch apart, are left in white upon its paper. Over
one of the halves of these parts a solution of stearine is passed. To
operate with the apparatus, in comparing two lights, the central spot
is first brought to invisibility, and the distances of the sources are
measured. A second determination is at once made by causing one of the
two other spots to disappear, and the mean of the two results is then
taken. As, at a maximum, there is a difference corresponding to 3/100
of a candle between the illumination of the two neighboring windows,
in the given conditions of the apparatus, the error is thus limited to
a half of this value, or 2 per cent. of that of one candle.

[Illustration: FIG. 5.--WILD'S APPARATUS FOR STUDYING MAGNETIC
VARIATIONS.]

Among the apparatus designed for demonstration in lecture courses, we
remarked a solenoid of Prof. Von Beetz for demonstrating the
constitution of magnets (Fig. 11), and in which eight magnetized
needles, carrying mica disks painted half white and half black, move
under the influence of the currents that are traversing the solenoid,
or of magnets that are bought near to it externally. Another apparatus
of the same inventor is the lecture-course galvanometer (Fig. 3), in
which the horizontal needle bends back vertically over the external
surface of a cylinder that carries divisions that are plainly visible
to spectators at a distance.

[Illustration: FIG. 6.--ELECTROMETER FOR ATMOSPHERIC OBSERVATIONS.]

Finally, let us cite an instrument designed for demonstrating the
principle of the Gramme machine. A circular magnet, AA', is inserted
into a bobbin, B, divided into two parts, and moves under the
influence of a disk, L, actuated by a winch, M. This system permits of
studying the currents developed in each portion of the bobbin during
the revolution of the ring (Fig. 12).

[Illustration: FIG. 7.--WIEDEMANN'S CURRENT BREAKER.]

To end our review of the scientific apparatus at the exhibition we
shall merely mention Mr. Van Rysselberghe's registering
thermometrograph (shown in Figs. 13 and 14), and shall then say a few
words concerning two types of registering apparatus--Mr. Harlacher's
water-current register and Prof. Von Beetz's chronograph.

[Illustration: FIG. 8.--WIEDEMANN'S BIFILAR GALVANOMETER.]

Mr. Harlacher's apparatus was devised by him for studying the deep
currents of the Elbe. It is carried (Fig. 15) by a long, vertical,
hollow rod which is plunged into the river. A cord that passes over a
pulley, P, allows of the apparatus, properly so called, being let down
to a certain depth in the water. What is registered is the velocity of
the vanes that are set in action by the current, and to effect such
registry each revolution of the helix produces in the box, C, an
electric contact that closes the circuit in the cable, F, attached to
the terminals, B. This cable forms part of a circuit that includes a
pile and a registering apparatus that is seen at L, outside of the box
in which it is usually inclosed. In certain cases, a bell whose sound
indicates the velocity of the current to the ear is substituted for
the registering apparatus.

[Illustration: FIG. 9.--WIEDEMANN'S GALVANOMETER FOR STRONG CURRENTS.]

Fig. 16 represents another type of the same apparatus in which the
mechanism of the contact is uncovered. The supporting rod is likewise
in this type utilized as a current conductor.

[Illustration: FIG. 10.--ZENGER'S DIFFERENTIAL PHOTOMETER.]

It now remains to say a few words about Prof. Von Beetz's chronograph.
This instrument (Fig. 17) is designed for determining the duration of
combustion of different powders, the velocity of projectiles, etc. The
registering drum, T, is revolved by hand through a winch, L, and the
time is inscribed thereon by an electric tuning fork, S, set in motion
by the large electro-magnet, E F. Each undulation of the curves
corresponds to a hundredth of a second. The tuning-fork and the
registering electro-magnets, G and H, are placed upon a regulatable
support, C, by means of which they may be given any position desired.

[Illustration: FIG. 11.--VON BEETZ'S SOLENOID FOR DEMONSTRATING THE
CONSTITUTION OF MAGNETS.]

The style, c, of the magnet, C, traces a point every second in order
to facilitate the reading. The style, b, of the electro-magnet, H,
registers the beginning and end of the phenomena that are being
studied.

[Illustration: FIG. 12.--APPARATUS FOR DEMONSTRATING THE PRINCIPLE OF
THE GRAMME MACHINE.]

The apparatus is arranged in such a way that indications may thus be
obtained upon the drum by means of induction sparks jumping between
the style and the surface of the cylinder. To the left of the figure
is seen the apparatus constructed by Lieutenant Ziegler for
experimenting on the duration of combustion of bomb fuses.

[Illustration: FIG. 13.--VAN RYSSELBERGHE'S REGISTERING
THERMOMETROGRAPH.]

Shortly after the drum has commenced revolving, the contact, K, opens
a current which supports the heavy armature, P, of an electro-magnet,
M. This weight, P, falls upon the rod, d, and inflames the fuse, Z, at
that very instant. At this precise moment the electro-magnet, H,
inscribes a point, and renews it only when the cartridge at the
extremity of the fuse explodes.

[Illustration: FIG. 14.--VAN RYSSELBERGHE'S REGISTERING
THERMOMETROGRAPH.]

This apparatus perhaps offers the inconvenience that the drum must be
revolved by hand, and it would certainly be more convenient could it
be put in movement at different velocities by means of a clockwork
movement that would merely have to be thrown into gear at the desired
moment. As it is, however, it presents valuable qualities, and,
although it has already been employed in Germany for some time, it
will be called upon to render still more extensive services.

[Illustration: FIG. 15.--HARLACHER'S APPARATUS FOR STUDYING DEEP
CURRENTS IN RIVERS.]

We have now exhausted the subject of the apparatus of precision that
were comprised in the Munich Exhibition. In general, it may be said
that this class of instruments was very well represented there as
regards numbers, and, on another hand, the manufacturers are to be
congratulated for the care bestowed on their construction.--_La
Lumiere Electrique_.

[Illustration: FIG. 16.--HARLACHER'S APPARATUS FOR STUDYING DEEP
CURRENTS IN RIVERS.]

[Illustration: FIG. 17.--VON BEETZ'S CHRONOGRAPH.]

* * * * *


COPPER VOLTAMETER.


Dr. Hammerl, of the Vienna Academy of Sciences, has made some
experiments upon the disturbing influences on the correct indications
of a copper voltameter. He investigated the effects of the intensity
of the current, the distance apart of the plates, and their
preparation before weighing. The main conclusion which he arrives at
is this: That in order that the deposit should be proportional to the
intensity of the current, the latter ought not to exceed seven amperes
per square decimeter of area of the cathode.

* * * * *


Speaking of steel ropes as transmitters of power, Professor Osborne
Reynolds says these have a great advantage over shafts, for the stress
on the section will be uniform, the velocity will be uniform, and may
be at least ten to fifteen times as great as with shafts--say 100 ft.
per second; the rope is carried on friction pulleys, which may be at
distances 500 ft. or 600 ft. so that the coefficient of friction will
not be more than 0.015, instead of 0.04.

* * * * *




A NEW OXIDE OF COPPER BATTERY.

By MM. F. DE LALANDE and G. CHAPERON.


We have succeeded in forming a new battery with a single liquid and
with a solid depolarizing element by associating oxide of copper,
caustic potash, and zinc.

This battery possesses remarkable properties. Depolarizing electrodes
are easily formed of oxide of copper. It is enough to keep it in
contact with a plate or a cell of iron or copper constituting the
positive pole of the element.

Fig. 1 represents a very simple arrangement. At the bottom of a glass
jar, V, we place a box of sheet iron, A, containing oxide of copper,
B. To this box is attached a copper wire insulated from the zinc by a
piece of India rubber tube. The zinc is formed of a thick wire of this
metal coiled in the form of a flat spiral, D, and suspended from a
cover, E, which carries a terminal, F, connected with the zinc; an
India-rubber tube, G, covers the zinc at the place where it dips into
the liquid, to prevent its being eaten away at this level.

The jar is filled with a solution containing 30 or 40 per cent. of
potash. This arrangement is similar to that of a Callaud element, with
this difference--that the depolarizing element is solid and insoluble.

[Illustration: FIG. 1.]

To prevent the inconveniences of the manipulation of the potash, we
inclose a quantity of this substance in the solid state necessary for
an element in the box which receives the oxide of copper, and furnish
it with a cover supported by a ring of caoutchouc. It suffices then
for working the battery to open the box of potash, to place it at the
bottom of the jar, and to add water to dissolve the potash; we then
pour in the copper oxide inclosed in a bag.

We also form the oxide of copper very conveniently into blocks. Among
the various means which might be employed, we prefer the following:

We mix with the oxide of copper oxychloride of magnesium in the form
of paste so as to convert the whole into a thick mass, which we
introduce into metal boxes.

The mass sets in a short time, or very rapidly by the action of heat,
and gives porous blocks of a solidity increasing with the quantity of
cement employed (5 to 10 per cent.).

[Illustration: FIG. 2.]

Fig. 2 represents an arrangement with blocks. The jar V, is provided
with a cover of copper, E, screwing into the glass. This cover carries
two vertical plates of sheet-iron, A, A', against which are fixed the
prismatic blocks, B, B, by means of India rubber bands. The terminal,
C, carried by the cover constitutes the positive pole. The zinc is
formed of a single pencil, D, passing into a tube fixed to the center
of the cover. The India rubber, G, is folded back upon this tube so as
to make an air-tight joint.

The cover carries, besides, another tube, H, covered by a split
India-rubber tube, which forms a safety valve.

The closing is made hermetical by means of an India rubber tube, K,
which presses against the glass and the cover. The potash to charge
the element is in pieces, and is contained either in the glass jar
itself or in a separate box of sheet-iron.

Applying the same arrangement, we form hermetically sealed elements
with a single plate of a very small size.

The employment of cells of iron, cast-iron, or copper, which are not
attacked by the exciting liquid, allows us to easily construct
elements exposing a large surface (Fig. 3).

[Illustration: FIG. 3.]

The cell, A, forming the positive pole of the battery is of iron plate
brazed upon vertical supports; it is 40 centimeters long by 20
centimeters wide, and about 10 centimeters high.

We cover the bottom with a layer of oxide of copper, and place in the
four corners porcelain insulators, L, which support a horizontal plate
of zinc, D, D', raised at one end and kept at a distance from the
oxide of copper and from the metal walls of the cell; three-quarters
of this is filled with a solution of potash. The terminals, C and M,
fixed respectively to the iron cell and to the zinc, serve to attach
the leading wires. To avoid the too rapid absorption of the carbonic
acid of the air by the large exposed surface, we cover it with a thin
layer of heavy petroleum (a substance uninflammable and without
smell), or better still, we furnish the battery with a cover. These
elements are easily packed so as to occupy little space.

We shall not discuss further the arrangements which may be varied
infinitely, but point out the principal properties of the oxide of
copper, zinc, and potash battery. As a battery with a solid
depolarizing element, the new battery presents the advantage of only
consuming its element, in proportion to its working; amalgamated zinc
and copper are, in fact, not attacked by the alkaline solution, it is,
therefore, durable.

Its electromotive force is very nearly one volt. Its internal
resistance is very low. We may estimate it at 1/3 or 1/4 of an ohm for
polar surfaces one decimeter square, separated by a distance of five
centimeters.

The rendering of these couples is considerable; the small cells shown
in Figs. 1 and 2 give about two amperes in short circuit; the large
one gives 16 to 20 amperes. Two of these elements can replace a large
Bunsen cell. They are remarkably constant. We may say that with a
depolarizing surface double that of the zinc the battery will work
without notable polarization, and almost until completely exhausted,
even under the most unfavorable conditions. The transformation of the
products, the change of the alkali into an alkaline salt of zinc, does
not perceptibly vary the internal resistance. This great constancy is
chiefly due to the progressive reduction of the depolarizing electrode
to the state of very conductive metal, which augments its conductivity
and its depolarizing power.

The peroxide of manganese, which forms the base of an excellent
battery for giving a small rendering, possesses at first better
conductivity than oxide of copper, but this property is lost by
reduction and transformation into lower oxides. It follows that the
copper battery will give a very large quantity of electricity working
through low resistances, while under these conditions manganese
batteries are rapidly polarized.

The energy contained in an oxide of copper and potash battery is very
great, and far superior to that stored by an accumulator of the same
weight, but the rendering is much less rapid. Potash may be employed
in concentrated solution at 30, 40, 60 per cent.; solid potash can
dissolve the oxide of zinc furnished by a weight of zinc more than
one-third of its own weight. The quantity of oxide of copper to be
employed exceeds by nearly one-quarter the weight of zinc which enters
into action. These data allow of the reduction of the necessary
substances to a very small relative weight.

The oxide of copper batteries have given interesting results in their
application to telephones. For theatrical purposes the same battery
may be employed during the whole performance, instead of four or five
batteries. Their durability is considerable; three elements will work
continuously, night and day, Edison's carbon microphones for more than
four months without sensible loss of power.

Our elements will work for a hundred hours through low resistances,
and can be worked at any moment, after several months, for example. It
is only necessary to protect them by a cover from the action of the
carbonic acid of the atmosphere.

We prefer potash to soda for ordinary batteries, notwithstanding its
price and its higher equivalent, because it does not produce, like
soda, creeping salts. Various modes of regeneration render this
battery very economical. The deposited copper absorbs oxygen pretty
readily by simple exposure to damp air, and can be used again. An
oxidizing flame produces the same result very rapidly.

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