The daily Cairo bulletin. (Cairo, Ill.) 1878-1???, 1882-07-14
Gun-Cotton.
fhe Power Of the Terrible and Dangerous Explo.

the ROVER OF tue Terrible ANA Dangerous EEplo-
sive.
In response to Superintendent Wal
lng's criticism, as reported in the Sun,
allow me to state few facts concern
ing explosives, which shall be happy
to demonstrate to him, if he will honor
Inc with his presence, at the College Of
the City of New York, or at Bellevue
Medical College II gunpowderis placed
in Il basket made OF coiled platinum
wire. and is then inserted in glass jar
arranged so that il can be exhausted of
air by an air-pump, on applying u cur
rent Of electricity to the coil, 50 as to
render the wire red-hot, the gunpOwder
will neitherexplode nor burn with flash.
1t will apparently boil, with a purple
light, and will require from five to
twenty seconds for its complete COM
bustlon, 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 pistol, rife or
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 tirccracker; 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 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 Il
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 mir by pump, if the coil iSmade
red-hot by an electric current, the gun
cotton will not explode, nor viii flame
or spark of fire be seen; the gun-cotton
will 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 cx-
ploslve variety when lighted do not en-
plodc; they merely burn with n brght
flash OF light When we prepare gun
cotton for class in chemistry we fire.
quently place lock of il OF a 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 u light If it
fails to ignite the powder it is the eNplo-
Siyc variety; if it sets fire to the powder
il is inferior in character Photograph
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 gun
cotton In stout receptacle. Now fire
it, and it will exhibit three times the
force of gun powder.
II Superintendent Walling will fill u
teaspoon with nitro-g lycerne and apply
to 1t n lighted match, he will find that
the nitro"glycorine will quietly and slow
~ burn, with grcen-colored flame, be-
cause It is only subjected to the pressure
of the air But II he places this amount
Of ntro-glycerne in closed vessel and
fires 1t, would advise him TO remain
at q respectful distance from it.
! have placed II fluid ounce of nitro
g'ycerine 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 ntro-glycerine
burns thrdily and without noise. With
sa,d battery | had previously fused and
Volatlllzed platinum, iridium aud other
refractory metals to demonstrate the in
'enslty OF the heat Yet, II n siugle drop
OF h'lrog'yccrnc Is placed on smooth
surface and struck n sudden blow, the
On p'oslon Is stunning to tho ear. The
samo law applies to giant powder, dy-
Mantle, rcnd-rock and other terrific eS-
plosives. They must have pressure to
exhibit their power. They burn quietly
anu SLOWLY withOut n. DIR. D0fcnluS