THE FISHMEN 



SO that he was independent of helpers above him. He 

 carried "an air-pump at his side", and by manipulating 

 this he could not merely supply himself with air but 

 "make himself heavier or lighter, as do fishes by contract- 

 ing or dilating their airbladders". 



One account says that "the objections of all other 

 diving-machines are obviated, particularly those regard- 

 ing the air, the moisture of which is clogged in respira- 

 tion, and by which it is rendered unfit for use again, 

 being taken from it by its circulation through the pipes, 

 to the sides of which it adheres, leaving the air as free 

 as before". Other accounts say that the diver inhaled 

 through his nose and exhaled through his mouth into a 

 short pipe which led into a leathern bag. BorelH was 

 certainly the pioneer of our age in self-contained breath- 

 ing mechanisms, with all respect to pioneers of past ages. 



Even if (as some assert) BorelH's apparatus was never 

 adequately tested, it certainly contributed a great deal 

 to the perfection of the diving-suit. Numbers of other 

 inventors in various countries began experimenting with 

 underwater apparatus as a result of his labours. One of 

 these, a Devonshire man named John Lethbridge, seems 

 to have had unusual success, contemporaneously with 

 BoreUi. 



Lethbridge's suit was of strong leather, and various 

 accounts agree that it contained "a hogshead of air", 

 and was so contrived that none of it could escape. Glass 

 was used for the front of the helmet. It was said that 

 when he had put on the suit he could not only walk 

 along the sea-bed near the shore, completely submerged, 

 but could also enter the cabins of sunken ships, "to 

 convey goods out of them at his pleasure". Lethbridge is 

 credited with carrying on all kinds of salvage operations 

 over a period of more than forty years, and with having 

 made a considerable fortune from the use of his invention. 



Borelli's ideas were materially advanced by Freminet, 

 a Frenchman, in 1772; and there can be no doubt that 



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