356 POPULAR LECTURES AND ADDRESSES. 



the water, there will suddenly come to be a 

 resistance of lolbs. against its motion. A 

 slight running on of the wheel one turn at 

 the most and the motion is stopped. The 

 instantaneous perception of the bottom, even 

 at so great a depth as 4,000 fathoms, when 

 this rule is followed is very remarkable, and 

 has been particularly noticed by Commander 

 Belknap in reports of his soundings in the 

 Pacific, presented to the United States Navy 

 Department. 



As to the modes of accelerating the 

 process : first, when there are plenty of men 

 available, instead of handles I put on each 

 end of the shaft of the auxiliary hauling-in 

 pulley, a smaller pulley with a sharp V- 

 groove. An endless rope passed half round 

 each of these V-pulleys, and kept tight by a 

 snatch block suitably placed inboard, allows 

 any number of men to haul, hand over hand, 

 or walking along the deck, as may be found 

 most convenient. Or when there is a donkey- 

 engine, it may be employed on one of the 



