The breastplate is fitted on its outer edge with metal screws and bands. The disposition of the screws corresponds with that of the holes in the india-rubber collar of the diving dress described below. There are other methods of making a watertight joint between the diver’s breastplate and the diving dress, but, as these are only mechanical differences, it will suffice to describe the Siebe-Gorman apparatus, as exclusively adopted by the British government. Whatever the shape or design of the helmet or dress, Siebe’s principle is the one in universal use to-day.
The metal tabs are for carrying the diver’s lead weights, which are fitted with suitable clips; the hooks—one on each side of the helmet—are for keeping the ropes attached to the back weight in position. The helmet and breastplate are fitted at their lower and upper parts respectively with gun-metal segmental neck rings, which make it possible to connect these two main parts together by one-eighth of a turn, a catch at the back of the helmet preventing any chance of unscrewing. The small eyes at the top of the helmet are for securing the diver’s air pipe and life line in position and preventing them from swaying.
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| Front view of Helmet. | Side sectional view of Helmet. |
A, Helmet. B, Breastplate. F, Emergency cock. G, Glasses in frames. H, Metal screws and bands. I, Metal tabs. J, Hooks for keeping weight ropes in position. L, Eyes to which air pipe and life line are secured. | K, Segmental neck rings. D, Air conduits. M, Telephone receiver. N, Transmitter. O, Contact piece to ring bell. |
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| Back view of Helmet. | Plan of Helmet. |
C, Air inlet valve. E, Regulating outlet valve. G, Glasses in frames. L, Eyes to which air pipe and life line are secured. P, Connexion for telephone cable. | |
| Fig. 3. | |
The Diving Dress is a combination suit which envelops the whole body from feet to neck. It is made of two layers of tanned twill with pure rubber between, and is fitted at the neck with a vulcanized india-rubber collar, or band, with holes punched in it corresponding to the screws in the breastplate. This collar, when clamped tightly between the bands and the breastplate by means of the nuts, ensures a watertight joint. The sleeves of the dress are fitted with vulcanized india-rubber cuffs, which, fitting tightly round the diver’s wrists, prevent the ingress of water at these parts also.
Boots.—These are generally made with leather uppers, beechwood inner soles and leaden outer soles, the latter being secured to the others by copper rivets. Heavy leather straps with brass buckles secure the boot to the foot. Each boot weighs about 16 ℔. Sometimes the main part of the boot-golosh, toe and heel, are in one brass casting, with leather upper part, heavy straps and brass buckles.
Lead Weights.—These weigh 40 ℔ each, and the diver wears one on his back, another on his chest. These weights and the heavy boots ensure the diver’s equilibrium when under water.
Belt and Knife and Small Tools.—Every diver wears a heavy waist-belt in which he carries a strong knife in metal case, and sometimes other small tools.
Air Pipe.—The diver’s air pipe is of a flexible, non-collapsible description, being made of alternate layers of strong canvas and vulcanized india-rubber, with steel or hard drawn metal wire embedded. At the ends are fitted gun-metal couplings, for connecting the pipe with the diver’s pump and helmet.