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HISTORY OF THE SEA. 



sea clanim." It consisted of a pair of forceps, kept apart hy 

 a bolt, and so contrived that when the bolt struck the ground 

 a heavy iron weight slipped down a spindle and closed the for- 

 ceps, which retained a portion of the mud, sand, or small 

 stones, from the bottom. With this instrument he sounded in 

 1,050 fathoms, and brought up six pounds of very soft mud, 

 using a whale line, made of the best hemp, and measuring 

 2J inches in circumference. 



The cup lead is another invention. With this there is a 

 pointed cup at the bottom of the lead, fastened to it with a rod 

 upon which a circular plate of leather plays, serving as a cover 

 to the cup. As it strikes the bottom, the cup is driven in the 

 mud, and on hauling up the cover is pressed into the cup by 

 the water, and brings up the mud it contains. The objection 

 to this is that it is too crude ; in its passage up, the water 

 washes away the mud, so that only on an average of once in 

 three times does the cup come up with anything in it ; and 

 deep sea soundings take too much time, and are too valuable, 

 to admit so large an average of loss. 



About 1854 Mr. J. M. Brooke, of the U. S. Navy, who was 

 at the time associated with Prof. Maury, so well known for his 

 labor in gathering and diffusing a knowledge of the currents 

 of the ocean, invented a deep sea sounding apparatus, which is 

 known by his name. It is still in use, and all the more recent 

 contrivances have been, to a great extent, only modifications and 

 improvements upon the original idea, that of detatching the 

 weight. The instrument is very simple. A 64-pound shot is 

 cast with a hole in it. An iron rod, with a cavity in its end, 

 fits loosely in the hole in the shot. Two movable arms at the 

 tnp of the rod are furnished with eyes holding ends of a sling 

 in which the ball hangs. The cavity at the end of the rod 

 is furnished with tallow, and the apparatus is let down. On 

 reaching the bottom, the rod is forced into the mud, the cavity 

 becomes filled with it, and there being no more tension, on the 



