2: Man Beneath the Waters 



IN THE SHALLOWS 



FROM the beginning of time man has been interested in the sea. He 

 went fishing to find the complement of the food with which the 

 land furnished him. He ranged along the rocky coasts in frail dugouts 

 and reached neighbouring isles. 



Later he began diving beneath the waves seeking sponges, corals 

 and pearls, using a technique which has hardly changed for thousands 

 of years. As man can live only brief moments on the reserve of air in 

 his body, the diver would make a faster dive by carrying with him 

 a heavy stone; then, holding on to a rope, he would have himself 

 hauled up as quickly as possible by the men who remained in the boat. 

 If he held a reed in his mouth, the other end of which emerged above 

 water-level, he could of course breathe beneath the water and prolong 

 his dive almost endlessly : but below a yard or two this method cannot 

 be used, as the pressure of the water restricts the chest, very soon 

 preventing all movement of the respiratory muscles. 



It is told of Alexander the Great that he had himself shut into a 

 crystal barrel and let down into the water by a rope held by his assist- 

 ants on board a boat. What he is said to have seen is more than 

 marvellous: in particular, a monster so long that, travelling along 

 before Alexander's eyes upon the command of an angel, it took three 

 days and three nights to pass. We have most eloquent engravings 

 dating from the Middle Ages, showing the king in his barrel and the 

 boat on the surface, with the boatmen. Obviously, here we have 

 merely a legend, which arose no doubt quite late in the Middle Ages. 

 Yet it is interesting, for the principle of the device used is that of the 

 bathysphere of Beebe and Barton. 



But let us come back to reality. When modern technique allowed 

 of the construction of pumps, of air- and water-tight vessels and of 

 flexible tubes, it was possible to work out the diving-suit with helmet 

 (too well-known to need description here) of which the principle is 

 derived from the diving bell. 



Then, more recently, it has been possible to do without the air- 

 supply tube, which has many inconvenient features and even serious 

 dangers. Thus the diver has become free, autonomous: he carries 



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