The evening telegraph. [volume] (Philadelphia [Pa.]) 1864-1918, 1871-01-12
DYNAMITE.

Nitro glycerine was discovered in the year
1S47, by an Italian named Ascogne Sobero,
but its practical application is entirely due to
the researches of Alfred Nobel, a Swedish
mining engineer. It does not explode when
brought into contact with fire, and remains
unchanged even when raised to the tempera-
ture of boiling water but at about forty
degrees Fahrenheit it becomes converted
into an icy mass, which merely requires fric-
tion to develop all its explosive qualities.
This popularity had been the cause of many
lamentable accidents, when M. Nobel COM
menced series of experiments with the view
Of rendering its employment comparatively
safe.
After some time, he found that mixing it
with about ten per cent of wood-spirit rem
dered it practically harmless, and this method
is now generally adopted. When required
for use, the wood-spirit can be removed, and
all the properties of the nitro -glycerine re-
stored by the simple addition of water, which,
mixing with the spirit, sets free, as it were,
the nitro-glycerine. The only drawback to
this plan is that, when the nitro-glycerine is
reconverted into its original state, it is of
course quite as dangerous as ever.
To obviste this M, Nobel has invented a
new mixture, which he terms dynamite. Z"
It consists of seventy-fve per cent. of nitro
elyceripe and twenty-five per cent. of very
fine sand, and is brownish-leoking powder,
something like sawdust, only greasy to the
touch. 1t burns without explosion when placed
in fire or brought into contact with lighted
match. If struck with hammer on an
anvil the portion struck takes fire
without infaming the dynaEnite around
it. AS q proof of the perfect secu-
rity with which it may be handled,
we may mention that M. Nobel has placed O
case containing about eight pounds of it
(equal to nearly eighty pounds of ordinary
powder) on brisk fire, and that the dyna-
mite was consumed without noise or shock
while similar case was flung from a height
of sixty five feet on a bold rock without pro-
ducing the slightest explosion. A weight of
two hundred pounds was then let fall from
height of twenty feet upon box of dynamite;
the box was smashed, but again there was no
explosion.
The usual method of firing dynamite is by
means of a copper capsule containing fulmi-
nate of silver-the latter being infamed
either by the ordinary slow-match, or by the
electric spark. The employment of this cap
sule and detonating composition is absolutely
essential for the explosion of dynamite. In
order to give some idea of the force deve-
loped by such an explosion, it may be men,
toned that spoonful of it placed upon
block of quartz, covered with bricks, and
fired, caused the quartz to be broken up into
pieces about the size of pea, and reduced
the bricks to powder. Like nitro-glycerine,
dynamite congeals at comparatively high
temperature; but, to restore it to its proper
condition, it is only necessary to put it in
warm place, or, if it is contained in closed
cartridges, to plunge it into warm water.
In mining operations dynamite possesses
many advantages over itro-glycerine, besides
those already mentioned.