350 THE OCEAN. 



the signal gun of the Government officer, and arrive 

 at the bank before daylight. At sunrise diving com- 

 mences, and the divers, divided into two parties, 

 descend alternately, the one set breathing while the 

 other is below. To expedite his descent, each man 

 has a conical piece of granite, through a hole in 

 which a rope is passed ; he grasps the rope with 

 the toes of his right foot, which he uses with nearly 

 the same pliancy as the fingers of his hands, and 

 taking in his left a net like an angler's landing-net, 

 seizes another rope in his right hand, and closes his 

 nostrils with his left thumb and finger. The weight 

 of the stone causes him to descend rapidly, and he 

 loses no time, but hastily fills his net with the oysters 

 he finds around. When he can retain his breath 

 no longer, he jerks the second rope, and is instantly 

 hauled to the surface by his fellows, leaving the stone 

 to be pulled up afterwards. Generally, from a 

 minute and a haK to two minutes is as long as a 

 diver can remain under water ; but Captain Percival 

 records a case in which a man " absolutely remained 

 under water full six minutes." The effects of so 

 long a submersion as even ordinarily takes place, are 

 severe, and manifest themselves by gushings of 

 water from the ears, mouth, and nose, and some- 

 times by discharges of blood. Yet they are ready 

 to take their turn again, frequently making forty 

 or fifty plunges a day, and bringing up at each turn 

 about a hundred oysters. 



The greatest danger to these adventurous men 

 arises from the sharks, to whose rapacity allusion 

 has before been made. But against them the poor 



