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THE POPULAR SCIENCE MONTHLY 



with the Lucas sounding machine and sounding cups. The machine 

 itself consists of a compact, triple-cylinder, compensating steam engine 

 which turns a reel on which five or six thousand fathoms of steel wire 

 are wound. Geared to tlie sheave over which the sounding wire runs is 

 a register, which indicates the number of fathoms of wire reeled out. 



Tub " Albatuoss " in Tort. (Photogrnph by DeLong.) 



For depths up to a thousand fathoms, a thirty-five pound shot is used 

 to carry the wire down, and for greater depths a shot of sixty pounds. 

 The shot are perforated with a two-inch hole so that they may be slipped 

 over the cylindrical brass sounding cup. This trips automatically on 

 striking the bottom, dropping the shot, while the sounding cup itpelf 

 sinks into the mud and brings up an ounce or two as a sample, with the 

 shells and hard remains of countless tiny animals which have played so 

 great a part in the formation of many of the present land masses of the 



