ON DEEP-SEA SOUNDING. 357 



endless ropes instead of a multitude of men 

 on the two. By multiplying the speed of 

 men, or using a donkey-engine in that way, 

 there is no difficulty in hauling in the wire 

 at the rate of about eight nautical miles an 

 hour. Thus the last 1,000 fathoms of wire, 

 with 34 Ibs. sinker attached, may in any case 

 be easily and safely got on board in seven 

 or eight minutes ; but a dozen men hauling 

 together might be required for this speed. 

 When greater lengths of wire are out, slower 

 speeds of hauliiig are required for safety. 

 With 3,000 fathoms of wire out, probably an 

 average speed of four miles per hour (or 400 

 feet per minute) would not give more than 

 from 100 to 120 Ibs. whole pull on the in- 

 coming part of the wire (or from 30 to 

 50 Ibs. resistance of the water, added to 

 34 Ibs. weight of sinker and 36 Ibs. weight in 

 water of the wire) ; and would, therefore, be 

 a safe enough speed. Of course, if there is 

 a heavy sea, augmenting considerably the 

 maximum stress above the mean stress, then 



