Barrel Torpedoes.
Barrel Torpedo.
Barrels are frequently used as torpedoes, being thoroughly caulked and pitched and strengthened as much as possible. They are slung with rope or chain slings, moored in position, and exploded either by contact or electrical fuses. In the majority of cases with defensive torpedoes at present, they are so arranged as to be fired either by contact or at will.
TORPEDO-FUSES.
Torpedo-fuses may be classified under four different heads; viz., Percussion, Friction, Chemical, and Electric.
A percussion fuse is one in which the flame is produced by a blow on some fulminating compound. Of such a type is the fuse of the Whitehead torpedo, which in principle is precisely that of the firing arrangement of breech-loading small-arms. The shock on the nose of the torpedo starts it back, releasing the firing-pin spring, which driving against a cap or fuse of fulminate, explodes it. The fuse of Singer’s torpedo cannot depend directly on the shock of collision to explode it, as the shock might be very light. As an intermediary, therefore, the heavy cover of the torpedo is used, which falls off when the torpedo is tilted, and by its descending weight releases the lock mechanism. This consists of a firing-pin and spring secured vertically underneath the torpedo and held retracted by a small pin. This pin is withdrawn by the falling cover, permitting the firing-pin to drive forward against the bottom of the torpedo. Just over the spot where it strikes is a short rod travelling in guides, the upper end being in contact with a small capsule of fulminate, which is exploded by the shock of the outside pin.
The Torpedo Time-Fuse
is in principle a lock mechanism in which the firing-pin catch is in connection with a train of clockwork. This clockwork being set to run for a certain length of time, the torpedo is set adrift to float against the vessel or obstruction, and the torpedo explodes at the end of the time for which it is set. The original and most crude form of this type of fuse is a candle cut to a certain length, the bottom being connected to a quick-match. It is not in this case a percussion fuse, as the quick-match communicates directly with the charge.
