Engineering Wonders of the World
Volume I

TORPEDOES. 435 through which the torpedo shall continue its passage to the hull. The charge itself consists of gun-cotton, either built up in sections shaped to fit the conical head, or else compressed into one solid mass which just fits the steel shell, and has a centre tube pierced for the reception of the detonator. When the head has been filled, a air is led through a valve, which automat- ically keeps the feed pressure constant, to the engines. At the back of the air chamber comes (3) the 'balance chamber. This contains the mech- anism for keeping the torpedo at the depth at which it has been arranged to run. It would take too long to explain the principle READY TO DISCHARGE A TORPEDO FROM ITS TUBE. (Photo, Gale and Polden.) thin containing plate is placed over the back of it, and it is fitted directly on to the next of the six sections—(2) the air chamber. This is a cylinder having walls from J to | of an inch thick, and capable of withstanding a pressure of 2,250 lbs. to the square inch. It is made of the very finest high-tensile steel, and only a few firms are entrusted with its manufacture. The result of the explosion of an air-cylinder charged to the enormous pressure used can best be left to the imagination. At the top of the rear end of the air chamber is a small tube—the supply tube—by which the in detail, but briefly stated the movements of the torpedo in the horizontal sense are con- trolled by the pressure of the surrounding water at various depths upon a very delicate movable “ hydrostatic disc ” in the wall of the outer hull. The disc is made water-tight by an india-rubber joint, and is pushed out by a spiral spring inside, which can be ad- justed to equal the pressure exerted by the water at various depths. In conjunction with the disc a pendulum works according to the inclination of the torpedo. Both are connected with a “servo-motor,” a