734 



HISTORY OF THE SEA. 



the dredge, and the dredge was dragged directly from the vea 

 sel, owing to the great weight and spring of the rope the arms 

 would be continually lifted up, and the lip of the dredge be 

 prevented from scraping. In very deep water this operation 

 of steaming up to windward until the dredge rope is nearly 

 perpendicular, after drifting for half an hour or so to leeward, 

 is usually repeated three or four times. At 8:50 P. M. haul- 

 ing-in is commenced, and the donkey-engine delivers the rope 

 at a little more than a foot a second. A few moments before 

 1 o'clock in the morning the weights appear, and a little after 

 one, eight hours after it was cast, the dredge appears and is 

 safely landed on deck, having in the meantime made a journey 

 of over eight miles. The dredge, as the result of this haul, 

 contained hundred weight of characteristic pale grey Atlan- 

 tic ooze. The total weight brought up by the engine was as 

 follows : 



2,000 fathoms of rope, 4,000 

 1,000 " " 1,500 



5,500 



Weight of rope reduced to J in water 1,375 

 Dredge and bag 275 

 Ooze 168 

 Weight attached _224 



2,042 pounds. 



« 



Tn many of the dredgings at all depths it was found that 

 while few objects of interest were brought up within the 

 dredge, many echinoderms, corals and sponges came to the sur- 

 face sticking to the outside of the dredge bag, and even to the 

 first few fathoms of the rope. The experiment was therefore 

 tried of fastening to a rod attached to the bottom of the 

 dredge bag, a half dozen swabs, such bundles of hemp as are 

 used on ship-board for washing the decks. The result was 

 marvelous; the tangled hemp brought up everything rough 

 and movable that came in its way, and swept the bottom of the 

 ocean as it would have swept the deck. So successful was 

 this experiment, that the hempen tangles are now regarded as 



