THE FISHMEN 



The diver required only one attendant. He was enabled 

 to move freely among wreckage, and he could signal to 

 the surface efficiently. The suit became the standard 

 equipment for all kinds of underwater operations, and 

 was given rigorous tests — at the flooding of the Severn 

 Tunnel, for instance, and on various occasions when 

 mines were flooded, as at the Killingworth Colliery in 

 1882. 



Many improvements have been effected in diving-suits 

 since. A modification of the closed-circuit type of breath- 

 ing apparatus used by frogmen in World War II pre- 

 vented bubbles ascending to the surface, which might 

 have been detected in enemy harbours, either visually or 

 by sound-devices. 



A Frenchman named Le Prieur designed a device in 

 the 'thirties consisting of a tank of compressed air worn 

 across the chest by a naked diver, and connected to a 

 mouthpiece by a rubber hose. But he had to keep adjust- 

 ing a valve every time he ascended or descended, and so 

 precious air was wasted. Developing this invention, in 

 1942, Commandant J. Y. Cousteau and Emile Gagnan 

 designed an automatic regulator which became the 

 essential basis of the Aqualung system. 



It supplied breathable air at any depth that the 

 human body could endure. Le Prieur's apparatus could 

 only be used down to depths of twelve or fifteen feet. 

 Cousteau's first automatic compressed-air diving lung 

 enabled him to go down to twenty-five feet. It was an 

 oxygen rebreathing apparatus made from an oxygen 

 cylinder, a gas-mask canister containing soda-lime, and 

 a motor cycle inner tube. The gunsmith of the Suffren^ 

 on which Cousteau was serving, helped him to build it. 

 The soda-lime filtered the carbon dioxide from the 

 wearer's breath, and the equipment was worn on his 

 back, the air-tube ending in the transparent face 

 mask. 



Cousteau continually improved the Aqualung in the 



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