The Chemistry of Powder and Explosives - Sciencemadness Dot Org

DETONATORS 413
Amusements with Fulminating Silver. . . .
Segars.
Are prepared by opening the smoking end, and inserting
a little of the silver; close it carefully up, and it is done.
Spiders.
A piece of cork cut into the shape of the body of a spider,
and a bit of thin wire for legs, will represent with tolerable
exactness this insect. Put a small quantity of the silver underneath
it; and on any female espying it, she will naturally
tread on it, to crush it, when it will make a loud report.
Silver fulminate is still used for similar purposes in practical
jukes, in toy torpedoes (see Vol. I, p. 106), and in the snaps or
pull-crackers which supply the noise for bon-boms, joy-boms,
and similar favors.
Silver fulminate is insoluble in nitric acid, and is decomposed
by hydrochloric acid. It darkens on exposure to light. One liter
of water at 13° dissolves 0.075 gram of the salt, and at 30°
0.18 gram. The double fulminate of silver and potassium,
AgONC-KONC, is soluble in 8 parts of boiling water.
Detonators
The discovery of the phenomenon of initiation by Alfred Nobel
and the invention of the blasting cap 14 stand at the beginning
of the development of modern explosives, perhaps the most important
discovery and invention in the history uf the art. The
phenomenon has supplied a basis for the definition of high explosives,
that is to say, of those explosives, whether sensitive or
insensitive, which are incapable, without the invention, of being
used safely and controllably or perhaps even of being used at all.
- Nobel's experiments quickly led him to the form of the blasting
cap which is now in use, a cylindrical capsule, generally of copper
but sometimes of aluminum or zinc, filled for about half of its
length with a compressed charge of primary explosive. The charge
is fired either by an electric igniter or by a fuse, crimped into place,
its end held firmly against the charge in order that the chances of
a misfire may be reduced. Its action depends upon the development
of an intense pressure or shock. Fulminate of mercury was
the only substance known at the time of Nobel's invention which
could be prepared and loaded for the purpose with reasonable
safety, and caps loaded with straight fulminate were the first to
14 Nobel, Brit. Pat. 1,345 (1867).