Submarine Appliances And Their Uses
Deep Sea Diving, &c., &c.

Front Tap.—A small gun-metal cock (sometimes called the “spitcock”) is fitted on the left side of the face glass ; when the handle is vertical the tap is closed; when the handle, is turned outwards the tap is open. Its use is explained on page 55. Sometimes a wheel valve is fitted here instead of the cock as described. Brass hooks are fitted on each side of the neck, over which the lanyards of the lead weights pass. 1 he front and back weights are of lead, and are shaped to fit close to the body. They have gun-metal clips to fasten to the studs on the front of the corselet, or they may be fitted with lanyards for slipping. I he Diving Dress is made of solid sheet indiarubber, between two layers of tanned twill. It has an inner and an outer collar, the inner one (sometimes called the “bib ”) of the same material as that of the dress, to pull up round the neck, and the outer one, of vulcanised indiarubber, to go over the breastplate to form a watertight joint. The cuffs are also of vulcanised indiarubber, and fit tightly round the wrists, making, when secured by the vulcanised indiarubber rings, a watertight joint, at the same time leaving the diver’s hands free. Rings for Wrists.—These are made of vulcanised indiarubber, and go over the indiarubber cuffs to form a watertight joint; two or more may be required on each wrist. They are made in three patterns : (1 and 2) Broad and Narrow, plain ; and (3) Broad, fluted. The Broad plain ring is worn one half on the end of the diver’s cuff, the other half on his wrist. In the case of the Outed ring, the beaded edge of the diver’s cuff rests in the recessed part of the ring. Air Pipe.—Air pipes are made in 30ft., 45ft., 50ft. and 60ft. lengths; and are fitted with suitable gun-metal couplings at each end. The pipe is made in sinking and ■floating patterns. In cases where both kinds are used, the floating should be connected to the diver's helmet, and the sinking to the air pump. This arrangement prevents the pipe from being heavy on the diver, and at the same time keeps the upper part of the pipe from floating up, and perhaps fouling propellers, etc. Double male connecting pieces are provided, which enable two female ends of two lengths of air pipe to be joined together, and similarly double female connections are provided for joining up two male ends. 29