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

Fig. No. 28 HISTORICAL.—THE EVOLUTION OF THE DIVING DRESS AND DIVING BELL.* 1 he earliest record of the art of diving having been practised for a purpose of utility occurs in that part of Homer’s Iliad in which he compares the fall of Hector’s Unassisted charioteer to the action of a diver. Thus it would seem that the art was known ap- Natural proximately eleven centuries before the Christian era. Thucydides is the first to men- Dwtng. tion employment of divers for mechanical work under water. He relates that divers were employed during the defence of Syracuse (b.c. 215-212) to saw down the barriers which had been constructed below the surface of the water with the object of obstructing and damaging any Grecian war vessels which might attempt to enter the harbour. At the siege of Tyre (333 B.c.), too, clivers were ordered by Alexander the Great to impede or de- stroy the submarine defences of the besieged as they were erected. The purpose of these obstructions was analagous to that of the submarine mine of to-day. The employment of divers for the salvage of sunken property is first mentioned by Livy, who records that in the reign of Persius considerable treasure was recovered from the sea. By a law of the Rhodians, their clivers were allowed a proportion of the value recovered, varying with the risk incurred, or the depth from which the treasure was salved. For instance, if the diver raised it from a depth of eight cubits (12ft.) he received one third for himself; if from six- teen cubits (24ft.) one half; but upon goods lost near the shore, and recovered from a depth of two cubits (36111.) his share was only one tenth. In passing, we must not forget the well-known case of the piscatorial contest between Antony and Cleopatra. Antony, wishing to prove his skill as an angler before the object of his adoration, sent down a diver secretly with a fish previously caught to attach it to his hook. The trick was speedily discovered by Cleopatra, who des- patched another diver to fix a salted fish on the hook. These are examples of unassisted diving as practised by the Ancients. Their primitive method, however, is still in vogue in some parts of the world—notably in the Ceylon Pearl Fisheries and in the Mediterranean Sponge Fisheries, and it may, therefore, be as well to mention the system adopted by the natural, or naked diver of to-day. 1 he volume and power of respiration of the lungs vary in different individuals, some persons being able to hold their breath longer than others, so that it naturally follows that one man may be able to stay longer under water than another. The longest time that a natural diver has been known to remain beneath the surface is about two minutes. Some pearl and sponge divers rub their bodies with oil, and put wool, satu- rated with oil, in their ears. Others hold in their mouth a piece of sponge soaked in oil, which they renew every time they descend. It is doubtful, however, whether these expedients are beneficial. 1 he men who dive in this primitive fashion take with them a flat stone with a hole in the centre : to this is attached a rope, which is secured * Copyright by R. H. Davis in the U.S.A.