250 THE BOTTOM OF THE SEA. 



cause irregularity in the escape of tlie bubbles, and 

 if the pumpers continued their work they might, quite 

 unconsciously, fur a long time continue to send air to 

 a corpse. With the new apparatus, however, the 

 escaping air affords constant evidence of the health 

 of the diver. The moment he requires help, his at- 

 tendants are on the qui vive, while in the former case 

 they could know nothing of his condition. This ad- 

 vantage in the new apparatus can hardly fail to en- 

 courage the most timil. 



Further, he who wears the old apparatus exposes 

 his life much more than he who uses the apparatus of 

 Rouqiiayrol and Denayrouze. His life, or at least 

 the security and duration of his labours, depend en- 

 tirely on the strength and substance of his clothino. 

 In the new system the caoutchouc dress serves only 

 to protect the diver from the cold. It requires, 

 therefore, much less solidity than the other, and thus 

 leaves the diver greater freedom of motion. 



MM. Eouquayrol and Denayrouze have done 

 everything to bring their incontestably useful ap- 

 paratus within the reach of all. Experiei^ced and 

 intelligent divers are no longer requisite — neither is 

 it necessary to employ workmen accustomed by long 

 practice to work the pump in a uniform manner. We 

 have already seen how the diver is enabled to obtain 

 a regular sup})ly of air in spite of any irregularities 



