It is not a suitable explosive agent for torpedoes, on account of its liability to be injured by damp, as well as its not being sufficiently violent, though for the sake of convenience, &c., it is often employed for such work.
The effect produced by the explosion of a charge of gunpowder, ignited by the ordinary method, is that of an uplifting rather than a shattering effect.
This evil may be greatly remedied, when gunpowder is used as the charge of a torpedo, by firing it with a detonator, by which means its fullest explosive effect is developed.
Picric Powder.—The picrates are salts of picric acid.
Picric acid is formed by the action of nitric acid on carbolic acid.
The picrate employed by Professor Abel is prepared from picric acid and ammonium. This preparation, or salt mixed with nitre (saltpetre), forms Abel's picric powder.
Properties, &c.—It is prepared for use in a similar manner to gunpowder, and it can be handled in the same way.
It is less violent than dynamite or gun-cotton, though much more so than gunpowder.
It is difficult to explode it by blows or friction.
If flame be applied to it, the part touched burns, but the combustion does not become general.