Scientific American Supplement, No. 711 | Page 7

the barrel of the gun is 25 tons, that of the
steel shell 215 kilogrammes (about 430 lb.), that of the brown powder
charge 100 kilogrammes; initial velocity of projectile, 610 meters;
penetration, 0.524 meter iron; longest range, 17 kilometers (about 10½
English miles); range at 15 deg. elevation, 10 kilometers. The six
15-centimeter guns are placed in a kind of machicouli arrangement in
two tiers on each of the broadsides, so that always four guns can fire in
the direction of the keel to the front and rear. The weight of the barrel
of the gun is each six tons, that of the steel shells 51 kilogrammes, that
of the charge 22 kilogrammes; initial velocity, 610 meters.
The 11 quick-firing guns are partly placed along the broadsides, partly
in the masts, of which there are two. The triple expansion engines,
having each a bronze screw of 4.42 meters diameter, with three blades
and a rise of 6.3 meters, make with natural draught 105 revolutions,
and with forced draught 120. The pumping apparatus are able to lift in
one hour 400 tons of water. The front boiler room contains a special
cylindrical boiler for the working of the electrical apparatus, for
hydraulic pumps of the artillery service, for anchor windlasses,
ventilators, fire engines, etc. The whole engines weigh 890 tons. The
bunkers have a capacity for 660 tons of coal, which allows for a run of
4,500 sea miles.
* * * * *

CLARK'S GYROSCOPIC TORPEDOES.

Figs. 1 and 2 represent, upon a scale of about 1/10, two types of
torpedoes, the greatest number possible of the parts of which are made
revolvable, so as to render the torpedoes as dirigible as the gyrating
motion permits of.
Fig. 1 represents an electric torpedo actuated by accumulators, A A,
keyed upon the shaft, and revolving along with the gearings. At the
beginning of the running, the accumulators are not all coupled, but
under the action of a clockwork movement which is set in motion at the
moment of starting, metallic brushes descend one after another upon
the collectors, B, and set in action new batteries for keeping constant or,
if need be, accelerating the speed at the end of the travel.
[Illustration: Fig. 1.]
[Illustration: Fig. 2. CLARK'S GYROSCOPIC TORPEDOES.]
Fig. 2 represents an air torpedo proposed by the same inventor. The air
reservoir, C, revolves along with the gearings under the action of the
pneumatic machine, D. The central shaft is hollow, so as to serve as a
conduit. The admission of air into the slide valve of the machine is
regulated by a clockwork which actuates a slide in an aperture whose
form and dimensions are so calculated that the speed remains as
constant as possible toward the end of the travel.
The trajectory of the two torpedoes is regulated by a cylindrical bellows,
F, which gives entrance to the sea water. The springs shown in the
figure balance the hydraulic pressure. The tension of these springs is
regulated by the rod, H, according to the indications of the scale of
depths, I.
When the torpedo reaches too great a depth, the action of the springs
can no longer balance the increase of the hydraulic pressure, and the
accumulation of the charge in the rear causes the front to rise toward
the surface. When the torpedo reaches the surface, a contrary action is
produced.--_Revue Industrielle._
* * * * *

THE FIRST STEAMBOAT ON THE SEINE.
[Illustration: FIRST STEAMBOAT BUILT ON THE SEINE.]
The accompanying engraving represents the remarkable steamboat that
the unfortunate Marquis de Jouffroy constructed at Paris in 1816, after
organizing a company for the carriage of passengers on the Seine. De
Jouffroy, as well known, made the first experiment in steam navigation
at Lyons in 1783, but the inventor's genius was not recognized, and he
met with nothing but deception and hostility. With the obstinacy of
men of conviction, he did not cease to prosecute his task. He assuredly
had an inkling of the future in store for the invention that he was
offering to humanity.
The paddle wheel boat that he constructed at Paris in 1816 did not
succeed any better than its predecessors; it was remarkable nevertheless
in appearance and structure.
The engine was forward, as shown in the engraving, which is copied
from a composition of Dubucourt's.
The company organized by the marquis was ruined, and, as well known,
the unfortunate inventor himself died in poverty in 1832, at the age of
eighty-one years.--_La Nature._
* * * * *

THE ELECTRIC MOTOR TESTS ON THE NEW YORK
ELEVATED RAILROAD.
The American Institute of Electrical Engineers at its last meeting of the
season, held June 25, again considered the subject of electrical traction,
the paper presented by Mr. Leo Daft being based