Besides their use as ballistic agents, gun cotton, dynamite, and explosive gelatin in their ordinary condition have found employment and been adopted as service explosives in military and naval mining, as their great energy and the violence with which they
explode, even when unconfined, especially adapt them for use in the various kinds of torpedoes and mines which are in vogue in the service.
One form of these torpedoes was attached to the end of a spar or pole which was rigged out from the bow of a launch or vessel so that it could be thrust under the enemy's vessel, and the detonators of such spar torpedoes were not only connected with electric generators, so that they could be fired at will, but they, in common with mines, were frequently provided with a system of levers so arranged that the enemy's vessel fired the torpedoes and mines automatically as it came in contact with the levers. It was with such a contact-spar torpedo, containing thirty-three
pounds of gun cotton, that the schooner Joseph Henry was blown up in Newport Harbor in 1884.
There are many types of the automobile torpedo. Among them the Hall, Patrick,-Whitehead, and Howell may be cited.