Scientific American Supplement, No. 363, December 16, 1882

V >> Various >> Scientific American Supplement, No. 363, December 16, 1882

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[Illustration: GOULIER'S TUBE GAUGE. (Plan and longitudinal and
tranverse sections.)]

The extremity of a brass tube, T, 0.5 to 0.6 of a meter in length and
smaller in diameter than the tube to be gauged, is cut into four narrow
strips a few centimeters in length. The extremity of each of these
strips is bent toward the axis of the tube. Two of them, m and m',
opposite each other are made very flexible, and carry, riveted to their
extremities, two steel buttons, the heads of which, placed in the
interior, have the form of an obtuse quoin with rounded edge directed
perpendicular to the tube's axis. The other extremities of these buttons
are spherical and polished and serve as caliper points in the operation
of measuring. These buttons are given a thickness such that when the
edges of their heads are in contact, the external diameter of the tube
exceeds the distance apart of the two calibrating points by more than
one millimeter. But such distance apart is increased within certain
limits by inserting between the buttons a German silver wedge, L,
carried by a rod, t, which traverses the entire tube, and which is
maneuvered by a head, B, fixed to its extremity. This rod carries a
small screw, v, whose head slides in a groove, r, in the tube, so as
to limit the travel of the wedge and prevent its rotation. Beneath the
head, B, the rod is filed so as to give it a plane surface for the
reception of a divided scale. A corresponding slit in the top of the
tube carries the index, I, of the scale. The principal divisions of the
scale have been obtained experimentally, and traced opposite the index
when the calibrating points were exactly 7, 8, 9 etc., millimeters
apart. As the angle of the wedge is about one tenth, the intervals
between these divisions are about one centimeter. These intervals are
divided into ten parts, each of which corresponds to a variation in
distance of one tenth of a millimeter.

To calibrate a glass tube with this instrument, the tube is laid upon
the table, the gauge is inserted, and the buttons are introduced into
the section desired. The flat side of the head, B, being laid on the
table, arranges, as shown in the figure, the buttons perpendicular to
it. Then the measuring wedge is introduced until a stoppage occurs
through the contact of the buttons with the sides of the tube. Finally,
their distance apart is read on the scale. Such distance apart will be
the measure of a diameter or a chord of the tube's section, according as
the buttons have been kept in the diametral plane or moved out of it. In
order that the operator shall not be obliged to watch the position of
the line of calibrating buttons in obtaining the diameter, the following
arrangement has been devised: The sides of the measuring wedge are filed
off to a certain angle, and the ends of the corresponding strips, d and
d', are bent inward in the form of hooks, whose extremities always rest
on the faces of the directing wedges. The length of these hooks and the
angle of the wedge are such that the distance apart of the rounded backs
of the directing strips is everywhere less, by about one-thirtieth, than
that of the calibrating buttons. From this it will be seen that if the
wedge be drawn back, and inserted again after the tube has been turned,
we shall measure the diameter that is actually vertical. It becomes
possible, then, to determine the greatest and smallest diameters in a
few minutes; and, supposing the section elliptical, its area will be
obtained by multiplying the product of these two diameters by pi/4.

From the description here given it will be seen that Colonel Goulier's
apparatus is not only convenient to use, but also permits of obtaining
as accurate results as are necessary. Two sizes of the instrument are
made, one for diameters of from 7 to 10.5 mm., and the other for those
of from 10 to 15.5 mm. It is the former of these that is shown, of
actual size, in the cuts.

* * * * *

SOLDERING WITHOUT AN IRON.

The following method for soldering without the use of a soldering iron
is given in the _Techniker_:

The parts to be joined are made to fit accurately, either by filing
or on a lathe. The surfaces are moistened with the soldering fluid, a
smooth piece of tin foil laid on, and the pieces pressed together and
tightly wired. The article is then heated over the fire or by means of
a lamp until the tin foil melts. In this way two pieces of brass can be
soldered together so nicely that the joint can scarcely be found.

With good soft solder, nearly all kinds of soldering can be done over
a lamp without the use of a "copper." If several piaces have to
be soldered on the same piece, it is well to use solder of unlike
fusibility. If the first piece is soldered with fine solder composed of
2 parts of lead, 1 of tin, and 2 of bismuth, there is no danger of its
melting when another place near it is soldered with bismuth solder, made
of 4 parts of lead, 4 of tin, and 1 of bismuth, for their melting points
differ so much that the former will not melt when the latter does. Many
solders do not form any malleable compounds.

In soldering together brass, copper, or iron, hard solder must be
employed; for example, a solder made of equal parts of brass and silver
(!). For iron, copper, or brass of high melting point, a good solder is
obtained by rolling a silver coin out thin, for it furnishes a tenacious
compound, and one that is not too expensive, since silver stretches out
well. Borax is the best flux for hard soldering. It dissolves the oxides
which form on the surface of the metal, and protects it from further
oxidation, so that the solder comes into actual contact with the
surfaces of the metal. For soft soldering, the well-known fluid, made by
saturating equal parts of water and hydrochloric acid with zinc, is to
be used. In using common solder rosin is the cheapest and best flux. It
also has this advantage, that it does not rust the article that it is
used on.--_Deutsche Industrie Zeitung_.

* * * * *

WORKING COPPER ORES AT SPENCEVILLE.

From a letter in the Grass Valley _Tidings_ we make the following
extracts:

The Spenceville Copper Mining Company have 43 acres of copper-bearing
ground and 100 acres of adjoining land, which was bought for the timber.
There are a hoisting works, mill, roasting sheds, and leaching vats on
the ground, and they cover several acres.

On going around with Mr. Ellis, the first place we came to was the mine
proper, which is simply an immense opening in the ground covering about
one half of an acre, and about 80 feet deep. It has an incline running
down into it, by which the ore is hoisted to the surface. Standing on
the brink of this opening and looking down, we could see the men at
work, some drilling, others filling and running the cars to the incline
to be hoisted to the surface.

The ore is found in a sort of chloritic slate and iron pyrites which
follow the ledge all around. The ore itself is a fine-grained pyrite,
with a grayish color, and it is well suited by its sulphur and low
copper contents, as well as by its properties for heap roasting. In heap
roasting, the ore is hand-broken by Chinamen into small lumps before
being hoisted to the surface. From the landing on the surface it is run
out on long tracks under sheds, dumped around a loose brick flue and on
a few sticks of wood formed in the shape of a V, which runs to the flues
to give a draught. Layers of brush are put on at intervals through the
pile. The smaller lumps are placed in the core of the heap, the larger
lumps thrown upon them, and 40 tons of tank residues thrown over all to
exclude excess of air; 500 lb. of salt is then distributed through the
pile, and it is then set afire. After well alight the draught-holes are
closed up, and the pile is left to burn, which it does for six months.
At the expiration of that time the pile is broken into and sorted, the
imperfectly roasted ore is returned to a fresh roast-heap, and the rest
trammed to the

LEACH-VATS.

These are 50 in number, 10 having been recently added. The first 40 are
four feet by six feet and four feet deep, the remaining 10 twice as
large. About two tons of burnt ore is put in the small vats (twice as
much in the larger ones), half the vats being tilled at one time, and
then enough cold water is turned in to cover the ore. Steam is then
injected beneath the ore, thus boiling the water. After boiling for some
time, the steam is turned off and the water allowed to go cold. The
water, which after the boiling process turns to a dark red color, is
then drawn off. This water carries the copper in a state of solution.
The ore is then boiled a second time, after which the tank residues are
thrown out and water kept sprinkling over them. This water collects the
copper still left in the residues, and is then run into a reservoir, and
from the reservoirs still further on into settling tanks, previous to

PRECIPITATION,

and is then conducted through a system of boxes filled with scrap iron,
thus precipitating the copper.

The richer copper liquors which have been drawn from the tanks fire not
allowed to run in with that which comes from the dump heaps. This liquor
is also run into settling tanks, and from them pumped into four large
barrels, mounted horizontally on friction rollers, to which a very slow
motion is given. These barrels are 18 feet long and six feet six inches
deep outside measure. They are built very strongly, and are water-tight.
Ten tons of scrap iron are always kept in each of these barrels, which
are refilled six times daily, complete precipitation being effected in
less than four hours. Each barrel is provided with two safety valves,
inserted in the heads, which open automatically to allow the escape of
gas and steam. The precipitation of the copper in the barrels forms
copper cement. This cement is discharged from the barrels on to screens
which hold any lumps of scrap iron which may be discharged with the
cement. It is then dried by steam, after which it is conveyed into
another tank, left to cool, and then placed in bags ready for shipment,
as copper cement. The building in which the liquor is treated is the
mill part of the property, from which they send out 42 tons monthly of
an average of 85 per cent, of copper cement, this being the average
yield of the mine.

There are 23 white men and 40 Chinamen employed at the mine and the
mill. There are also several wood choppers, etc., on the company's
pay-roll. Eight months' supply of ore is always kept on hand, there
now being 12,000 tons roasting. The mine is now paying regular monthly
dividends, and everything argues well for the continuance of the same.

* * * * *

SIR WILLIAM THOMSON'S PILE.

The Thomson pile, which is employed with success for putting in action
the siphon recorder, and which is utilized in a certain number of cases
in which an energetic and constant current is needed, is made in two
forms. We shall describe first the one used for demonstration. Each
element of this (Fig. 1) consists of a disk of copper placed at the
bottom of a cylindrical glass vessel, and of a piece of zinc in the form
of a grating placed at the upper part, near the surface of the solution.
A glass tube is placed vertically in the solution, its lower extremity
resting on the copper. Into this tube are thrown some crystals of
sulphate of copper, which dissolve in the liquid, and form a solution of
a greater density than that of the zinc alone, and which, consequently,
cannot reach the zinc by diffusion. In order to retard the phenomenon of
diffusion, a glass siphon containing a cotton wick is placed with one of
its extremities midway between the copper and zinc, and the other in
a vessel outside the element, so that the liquid is sucked up slowly
nearly to its center. The liquid is replaced by adding from the top
either water or a weak solution of sulphate of zinc.

[Illustration: FIG. 1.--THE THOMSON PILE.(Type for demonstration.)]

The greater part of the sulphate of copper that rises through the liquid
by diffusion is carried off by the siphon before reaching the zinc, the
latter being thus surrounded with an almost pure solution of sulphate
of copper having a slow motion from top to bottom. This renewal of the
liquid is so much the more necessary in that the saturated solution of
sulphate of copper has a density of 1.166, and the sulphate of zinc
one of 1.445, There would occur, then, a mixture through inversion of
densities if the solution were allowed to reach a too great amount of
saturation, did not the siphon prevent such a phenomenon by sucking up
the liquid into the part where the mixture tends to take place. The
chemical action that produces the current is identical with that of the
Daniell element.

In its application, this pile is considerably modified in form
and arrangement. Each element (Fig 2) consists of a flat wooden
hopper-shaped trough, about fifty centimeters square, lined with sheet
lead to make it impervious. The bottom is covered with a sheet of copper
and above this there is a zinc grate formed of closely set bars that
allow the liquid to circulate. This grate is provided with a rim which
serves to support a second similar element, and the latter a third,
and soon until there are ten of the elements superposed to form series
mounted for tension. The weight of the elements is sufficient to secure
a proper contact between the zinc and copper of the elements placed
beneath them, such contact being established by means of a band of
copper cut out of the sheet itself, and bent over the trough.

[Illustration: FIG. 2.--THE THOMSON PILE. (Siphon Recorder Type.)]

On account of the large dimensions of the elements, and the proximity
of the two metals, a pile is obtained whose internal resistance is very
feeble, it being always less than a tenth of an ohm when the pile is
in a good state, and the electromotive force being that of the Daniell
element--about 1 08 volts.

Sometimes the zinc is covered with a sheet of parchment which more
thoroughly prevents a mixture of the liquids and a deposit of copper on
the zinc. But such a precaution is not indispensable, if care be taken
to keep up the pile by taking out some of the solution of sulphate of
zinc every day, and adding sulphate of copper in crystals. If the pile
is to remain idle for some time, it is better to put it on a short
circuit in order to use up all the sulphate of copper, the disappearance
of which will be ascertained by the loss of blue color in the liquid. In
current service, on the contrary, a disappearance of the blue color will
indicate an insufficiency of the sulphate, and will be followed by a
considerable reduction in the effects produced by the pile.

The great power of this pile, and its constancy, when it is properly
kept up, constitute features that are indispensable for the proper
working of the siphon recorder--the application for which it was more
especially designed.

This apparatus has been also employed under some circumstances for
producing an electric light and charging accumulators; but such
applications are without economic interest, seeing the enormous
consumption of sulphate of copper during the operation of the pile.
The use of the apparatus is only truly effective in cases where it is
necessary to have, before everything else, an energetic and exceedingly
constant current.--_La Nature_.

* * * * *

SIEMENS' TELEMETER

The accompanying cut illustrates a telemeter which was exhibited at the
Paris Exhibition of Electricity, and which is particularly interesting
from the fact that it is the first apparatus of this kind. It will be
remembered that the object of a telemeter is to make known at any moment
whatever the distance of a movable object, and that, too, by a direct
reading and without any calculation. In Mr. Siemens' apparatus the
problem is solved in the following manner:

The movable object (very often a vessel) is sighted from two different
stations--two points of the coast, for example--by two different
observers. The sighting is done with two telescopes, A1 and A2, which
the observers revolve around a vertical axis by means of two winches, K1
and K2, that gear with two trains of clockwork. There is thus constantly
formed a large triangle, having for its apices the movable point sighted
and the vertical axes, A1 and A2, of the two telescopes. On another
hand, at a point situated between the two telescopes, there is a table,
T T, that carries two alidades, a1v1, and a2v2, movable around their
vertical axes, a1 and a2. The line, a1 a2, that joins these axes is
parallel with that which joins the axes of the two telescopes; and the
alidades are connected electrically with the telescopes by a system
such that each alidade always moves parallel with the telescope that
corresponds to it. It follows from this that the small triangle that
has for apices, a1 a2, and the crossing point of the two alidades will
always be like the large triangle formed by the line that joins the
telescopes and the two lines of vision. If, then, we know the ratio of
a1, a2 to A1 A2, it will suffice to measure on one of the alidades the
distance from its axis to the point of crossing in order to know the
distance from the movable object to the axis of the corresponding
telescope. If the table, T T, be covered with a chart giving the space
over which the ship is moving, so that a1 and a2 shall coincide with the
points which A1 and A2 represent, the crossing of the threads of the
alidades will permit of following on the chart all the ship's movements.
In this way there maybe had a powerful auxiliary in coast defence; for
all the points at which torpedoes have been sunk may be marked on the
chart, and, as soon as the operator at the table finds, by the motion
of the alidades, that the ship under observation is directly over a
torpedo, he will be able to fire the latter and blow the enemy up.
During this time the two observers at A1 and A2 have only to keep their
telescopes directed upon the vessel that it has been agreed upon to
watch.

[Illustration: SIEMENS' ELECTRIC TELEMETER]

In order to obtain a parallelism between the motion of the alidades and
that of the corresponding telescopes, the winch of each of the latter,
while putting its instrument in motion, also sets in motion a Siemens
double-T armature electromagnetic machine. One of the wires of the
armature of this machine, connected to the frame, is always in
communication with the ground at E1 (if we consider, for example, the
telescope to the left), and the other ends in a spring that alternately
touches two contacts. One of these contacts communicates with the
wire, L1 and the other with the wire, L3, so that, when the machine is
revolving, the currents are sent alternately into L1 and L3. These two
latter wires end in a system of electro magnets, M1, provided with a
polarized armature. The motions of the latter act, through an anchor
escapement, upon a system of wheels. An axle, set in motion by the
latter, revolves one way or the other, according to the direction of the
telescope's motions. This axle is provided with an endless screw that
gears with a toothed sector, and the latter controls the rotatory axis
of the alidade. The elements of the toothed wheels and the number of
revolutions of the armature for a given displacement of the telescope
being properly calculated, it will be seen that the alidade will be able
to follow all the movements of the latter.

When it is desired to place one of the telescopes in a given position
(its position of zero, for example), without acting on the alidade,
it may be done by acting directly on the telescope itself without the
intermedium of the winch. For such purpose it is necessary to interrupt
communication with the mechanism by pressing on the button, q. If the
telescope be turned to one side or the other of its normal position,
in making it describe an angle of 90 deg., it will abut against stops, and
these two positions will permit of determining the direction of the
base.

The alidades themselves are provided with a button which disengages the
toothed sector from the endless screw, and permits of their being
turned to a mark made on the table. A regulating screw permits of this
operation being performed very accurately. In what precedes, we have
supposed a case in which the movable point is viewed by two observers,
and in which the table, T T, is stationed at a place distant from them.
In certain cases only two stations are employed. One of the telescopes
is then placed over its alidade and moves with it; and the apparatus
thus comprehends only a system of synchronous movements.

This telemeter was one of the first that was tried in our military
ports, and gave therein most satisfactory results. The maneuver of the
winch, however, requires a certain amount of stress, and in order that
the sending of the currents shall be regular, the operator must turn it
very uniformly. This is a slight difficulty that has led to the use
of piles, instead of the magneto-electric machine, in the apparatus
employed in France. With such substitution there is need of nothing more
than a movable contact that requires no exertion, and that may be guided
by the telescope itself.--_La Lumiere Electrique_.

* * * * *

PHYSICS WITHOUT APPARATUS.

_Experiment in Static Electricity_.--Take a pipe--a common clay one
costing one cent--and balance it carefully on the edge of a goblet, so
that it will oscillate freely at the least touch, like the beam of a
scales. This being done, say to your audience: "Here is a pipe placed
on the edge of a goblet; now the question is to make it fall without
touching it, without blowing against it, without touching the glass,
without agitating the air with a fan, and without moving the supporting
table"

[Illustration: CLAY PIPE ATTRACTED BY AN ELECTRIFIED GOBLET.]

The problem thus proposed may be solved by means of electricity. Take a
goblet like the one that supports the pipe, and rub it briskly against
your coat sleeve, so as to electrify the glass through friction. Having
done this, bring the goblet to within about a centimeter of the pipe
stem. The latter will then be seen to be strongly attracted, and will
follow the glass around and finally fall from its support.

This curious experiment is a pretty variation of the electric pendulum;
and it shows that pipe-clay--a very bad conductor of electricity--favors
very well the attraction of an electrified body.

Tumblers or goblets are to be found in every house, and a clay pipe
is easily procured anywhere. So it would be difficult to produce
manifestations of electricity more easily and at less expense than by
the means here described.--_La Nature_.

* * * * *

THE CASCADE BATTERY.

[Footnote: Lately read before the Society of Telegraph Engineers and
Electricians.]

By F. HIGGINS.

The battery which I have brought here to-night to introduce to your
notice is of the circulating kind, in which the alimentary fluid
employed passes from cell to cell by gravitation, and maintains the
action of the battery as long as it continues to flow. It cannot,
of course, compare with such abundant sources of electricity as
dynamo-electric machines driven by steam power, but for purposes in
which a current of somewhat greater volume and constancy than that
furnished by the ordinary voltaic batteries is required, it will, I
believe, be found in some cases useful. A single fluid is employed, and
each cell is provided with an overflow spout.

The cells are arranged upon steps, in order that the liquid may flow
from the cell on the topmost step through each successive cell by
gravitation [specimen cells were on the table before the audience] to
the reservoir at the bottom. The top and the bottom reservoirs are of
equal capacity, and are fitted with taps. The topmost tap is used to
regulate the flow of the solution, and the bottom one to draw it off. In
each cell two carbon plates are suspended above a quantity of fragments
of amalgamated zinc. The following is a sectional drawing of the
arrangement of the cell:

[Illustration]

A copper wire passes down to the bottom of the cell and makes connection
with the mercury; this wire is covered with gutta-percha, except where
immersed in the mercury. The pores of the carbon plates are filled
with paraffin wax. This battery was first employed for the purpose of
utilizing waste solution from bichromate batteries, a great quantity of
which is thrown away before having been completely exhausted. This waste
is unavoidable, in consequence of the impossibility of permitting such
batteries, when employed for telegraphic purposes, to run until complete
exhaustion or reduction of the solutions has been effected; therefore
some valuable chemicals have to be sacrificed to insure constancy in
working. The fragments of zinc in this cell were also the remains of
amalgamated zinc plates from the bichromate batteries, and the mercury
which is employed for securing good metallic connection is soon
augmented by that remaining after the dissolution of the zinc. It will
therefore be seen that not only the solution, but also the zinc and
mercury remnants of bichromate batteries are utilized, and at the same
time a considerable quantity of electricity is generated. The cells are
seven inches deep and six inches wide, outside, and contain about a
quart of solution in addition to the plates. The battery which I employ
regularly, consisting of 18 cells, is at present working nine permanent
current Morse circuits, which previously required 250 telegraphic
Daniell cells to produce the same effect, and is capable of working at
least ten times the number of circuits which I have mentioned; but as we
do not happen to have any more of such permanent current Morse circuits,
we are unable to make all the use possible of the capabilities of the
battery. The potential of one cell is from 1.9 to 2 volts with strong
solution, and the internal resistance varies from 0.108 to 0.170 of an
ohm with cells of the size described. In order to test the constancy of
the battery, a red heat was maintained in a platinum-iridium wire by the
current for six weeks, both day and night.

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