The Manitowoc pilot. [volume] (Manitowoc, Wis.) 1859-1932, 1882-06-29
Gun-Ootton.
The Power of the Terrible and Dangerous Explo-


sive
In response to Superintendent Wal
hng's criticism, as reported in the Sttn,
allow ne to state q few facts concern
ing explosives, which | shall be happy
to demonstrate to him, if he will honor
me with his presence. at the College of
the City of New York, or at Bellevue
Medical College. If gunpowderis placed
in basket made of coiled platinum
wire, and is then inserted in glass jar
arranged so that it can be exhausted of
air by an air-pump, on applying q cur
rent of electricity to the coil, so as to
render the wire red-hot, the gunpowder
willneither explode nor burn with a flash.
1t viii apparently boil, with a purple
light, and will require from five to
twenty seconds for its complete COM
bustion, depending on the quantity of
powder and the amount of air removed.
All know that gunpowder has its own
supply Of oxygen-it does not require
any from the air; for we shut out the
air when we load 3 pistol, n rifle or a
cannon. The nitrate of potash furnish
es the oxygen for the carbon and sulphur
of the powder, The cause of the tardy
combustion of the gunpowder in the eX-
hausted receiver is the diminished pres
sure.
But wrap the powder in paper, and
we have the firecracker; enclose the
powder in an iron sphere, and we have
the bOmb-shell. As the powder burns
under increased pressure produced by
its own gases, it explodes with increased
force. An ounce or even a pound of
powder, when burnt in the open air,
produces no explosive sound-merely a
puff.
The Eliminates of silver or mercury
which are used in percussion caps will
also burn slowly. when placed in the
platinum coil referred to and heated
red-hot after the air has been exhausted
from the glass jar. Yet in the open air,
when fired, they will explode with a
sharp sound.
If a lock of gun-cotton (of the most
explosive kind), say foot in length, be
suspended in glass jar with said plat
mum coil, and after removing the pres
sure Of air by pump, if the coil is made
red-hot by an electric current, the gun
cotton will not explode, nor will a flame
or spark of fire be seen; the gun-cotton
win gradually disappear.
Even under the pressure of the air,
or, in other words, in the open air, small
quantities of gun-cotton of the most eX-
plosive variety when lighted do not ex-
pIode; they merely burn with a bright
flash of light. When we prepare gun
cotton for a class in chemistry we fre-
quently place a lock of it on students
hand and fire it to show how quickly it
burns; for he scarcely feels it. This is
one of the trivial tests of its good quality.
Another is to place the gun-cotton on
gunpowder, then apply light. If it
fails to ignite the powder it is the eXplo-
sive variety; if it sets fire to the powder
it IS inIeliior in character. Photographs
ers' gun cotton, which is soluble in al
cohol and ether, and is used for making
collodion, will burn slower. If placed
On gunpowder it will ignite it.
Enclose the explosive variety of gum
cotton in a stout receptacle. Now fire
it, and it will exhibit three times the
force of gun powder.
If Superintendent Walling will fill a
teaspoon with nitro-glycerine and apply
to it a lighted match, he will find that
the nitro-giycerine viii quietly and slow
ly burn, with q green-colored flame, be-
cause it is only subjected to the pressure
of the air. But if he places this amount
of nitro-glyceriae in a closed vessel and
fires it, would advise him to remain
at a respectful distance from it.
have placed fluid ounce of nitro
glycerine in a metal cup, connected with
one pole of a galvanic battery, and on
applying the opposite pole of the bat
terry to said liquid, have shown before
medical class that the nitro-glycerine
burns tardily and without noise. With
said battery l had previously fused and
volatilized platinum, iridium aud other
refractory metals to demonstrate the in
tensity of the heat. Yet, if q single drop
OF nitro glycerine is placed on a smooth
surface and struck sudden blow, the
explosion is stunning to the ear. The
same law applies to giant powder, dy-
Mantle, rend-rock and other terrific ex-
plosiyes. They must have pressure to
exhibit their power. They burn quietly
and slowly without it.-Dr. DorenaatS
IN The Nea0 York San.