The Chemistry of Powder and Explosives - Sciencemadness Dot Org

NITROGIA'CERIN 211
velocities of detonation it supplies a basis for the comparison of
their total energies.
EXPANSION,
CUBIC
CENTIMETERS
Nitroglycenn 550
Nitiomanmte 560
Completed giincotton {132% N) 420
Blasting gelatin . . 580
65% Gelatin dynamite . 410
75% Guhr dynamite 325
Tetryl 360
Picric sieid 300
Tiinitiotoliionp 285
Mercury fulminate 150
For several years after the discovery uf nitroglycenn, the
possibility of using it as an explosive attracted very little interest
Indeed, it first came into use as a medicine, and the first
serious study on its preparation, after the work of Sobrero, was
made by J. E. dc Vnj, professor of chemistry in the Medical
School at Rotterdam, and published in the Dutch journal of
pharmacy, Tijdschnft voor wetensch. pharm., in 1855. The next
significant work Was done by Alfred Nobel who in 1864
patented -° improvements both in the process of manufactuiing
nitroglyccrin and in the method of exploding it No liquid explosive
had been successful in practical use. Nobel believed that he
had solved the difficulty by taking advantage (if the property of
nitroglyccrin of exploding from heat or from the shock of an
explosion A small glass vessel containing black powder was tu
be immersed in the nitroglyccrin and exploded. Another method
was by the local heat of an electric spark or of a wire electrically
heated under the surface of the nitroglyccrin. And another was*
the percussion cap. Nobel used black powder first in glass bulbs',
later in hollow wooden cylinders closed with cork stoppers-, then
a mixture of black powder and mercury fulminate, and later
fulminate in small lead capsules and finally in the cupper detonators
which arc still m general use. The invention of the blunting
cap depended upon the discovery of the phenomenon ol initiation,
and signalized the beginning of a new era m the history of
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