Evening star. [volume] (Washington, D.C.) 1854-1972, 1915-11-07
Properties of
Dynamite.

L
npnor,;+. smokeless powder? The
explanation is contain
ed in the fact of slow and rapid ex-
blossoms. Slow and progressive powders
suit the cartridge for the rifle and can
non. Scattering powders for bombs
and cartridges are destined to destroy
bridges, rails, etc. The progressive
powder acts on the ball or bomb dur
ing the time the projectile passes from
the breech to the muzzle; the shatter-
ing powder may burst the cannon or
the rife. These shattering explosives
are reserved for cases where a destruc-
tive effect is sought.
NJ. Henry LIE Chatelier, the eminent
chemist and metalIurgist, has recently
given interesting indications on the
different sorts of explosions.
The rapidity of explosion is extremely
variable. according to the explosive
and the conditions in which the ex-
plosive is placed, the mode of printing.
Let US take up the dynamite cartridge
and put fire to it. 1t burns as a torch.
slowly. Place it against the rails of
the railway and fire it with suitable
percussion cap; the rail will go OF
also. The rapidity of the explosion
varies from one explosive to another
and also for the same explosive of one
condition to another in almost unmeas-
ured limits The differences are of the
proportion of one to a million. In
certain composition the explosion may
occur million times quicker than in
another. 1t is that which constitutes
the danger of SCATTERING explosives,
ultra-rapid, exploding in free air in the
absence of all constraint. Under these
conditions black powder flares up
without causing an explosion. and
lighted dynamite burns slowly without
exploding. Dynamite exploding under
the action of suitable percussion cap
causes considerable damage by reason
of the suddenneSS of its tranSforma-
ton. The layers of surrounding air,
the ground, objects, act as so many
walls of obstacles opposing the expan-
sion of gases suddenly set free; from
these identical results to those Whlcn
occur if the explosive had been fnclosed
in an envelope.
Black powder cannot do else than
flare up; melinite cannot do else than
explode with loud noise: But dyna-
mite and guncotton can by processes
of Fabrication or of utilization be made
to flare up in place of exploding.
No one ignores the virtue of an eX-
plos;ve which does not depend only
on its personality or on
Uo1ue of the conditions which have
been made. The mode OF
fIlminS. printing plays very inn
portant role According to the priming
the same body burns or bursts, decom-
poses progressively or eNplodes violent
ly. Still again, the cartridge dynamite
burns inoffensively when we put fire to
1t: it explodes when it is fired by the
side of capsule of illuminate of mer-
curry. In one case one has put fire to it
it burns; in the other one has created
an explosive wave, and it explodes
That explosive wave is propa gated be-
sides to the surroundings. The mechan-
ical shock engendered is sufficient to
precipitate an explosion by influence.
The sensitiveness of explosives is
very variable. Heat at variable points
always explodes an explosive. The eX
plosive by profession" is sensitive and
unstable.
We think we know all the weak
nesses of the explosive. A dynamite
cartridge to which match is applied
expfodes instead of burning. Why?
Theoretically picric acid is insensIble
to heat. 1t does not cause 1t to explode.
And yet it has exploded in certain
fires Again, smokeless powder is pre-
sented as insensible to mechanical ac-
lions, and yet the contrary has been
seen. Is there chance or caprice in
their actions? The truth Is there is
neither. There is no such thing as
price" means simply conditions, which
one may think are known, but which
were unknown.
x
Besides, explosives are subjects Of al
terations which are said to be 'sponta-
neous"; that is, due to
Spontaneous causes which have not
Explosions. explosive becomes a
new parsonage Dynamite, when it has
reached year in age, is something
SUSPICIOUS and extra-unreliable. Gun
cotton was in the same category, and
before means were found
to stabilize and preserve it.
The most ancient explosive Is the |
classic cannon powder brought by