584 FISHERIES OF THE UNITED STATES. [72] 



verse motion releases the reel and it revolves freely without moving the 

 cranks. The register to record the amount of wire out is fastened to 

 the frame at the left of the reel, and is operated by a worm-wheel. A 

 small ratchet-wheel and pawl hold the reel in place when desired. The 

 reel is unshipped by simply unscrewing one nut on the left crank, 

 which releases the shaft, allowing it to be withdrawn, and leaving the 

 ratchet, worm-wheel, and left crank in position. By means of a tackle 

 designed for this purpose, one man can easily ship and unship the 

 reel. 



"The guiding pulley carries a small arm near the upper end of its 

 shaft or spindle, which works through a slot in the casting. A small 

 cord is attached to the arm and made fast to the free end of the friction 

 rope, the standing part being hooked to a small metal eye in the frame 

 over the reel. By this arrangement the friction is intended to act auto- 

 matically in the following manner : The machine being ready for a cast, 

 the small friction line is hauled taut before the lead is bent, and while 

 the guiding pulley is up in its place. In this condition it requires a 

 strong man to move the reel, but, the lead being bent and suspended, 

 it compresses the spring and drags the pulley down sufficiently to slacken 

 the friction rope and allow the reel to move with comparative freedom. 

 The instant the lead strikes bottom, however, or the weight is re- 

 moved from any cause, the pulley flies up, putting a strain on the fric- 

 tion rope, which stops the reel at once. It acts also as a check in pay- 

 ing out, the friction being governed by the weight suspended on the 

 guide pulley, it being necessary to keep the sounding wire under con- 

 stant strain, like the spring of a clock." 



The original machine constructed by Lieutenant Tanner had a reel 

 measuring only 11.43 inches in diameter, with a carrying capacity of 

 600 fathoms of wire. One turn around the reel was equal to half a 

 fathom, and the entire apparatus weighed 96 pounds. Ordinary sound- 

 ing leads of 12 to 20 pounds weight were used. The machine in regular 

 use during the past two years has been considerably larger, the reel 

 having twice the diameter, and space for 2,000 fathoms of wire. It 

 weighs 128 pounds, and contains many improvements over the smaller 

 machine, as described above. The example displayed is of this pattern. 

 The smaller machine is still used at the stern of the Fish Hawk, with 

 Basnett's patent atmospheric lead, by means of which slight depths 

 may be measured while running at full speed. The positions assigned 

 to the sounding machines on the steamer Fish Hawk are illustrated in 

 the enlarged photographic views of that steamer. 



Sigsbee's Correction Curve, or method of ascertaining the true depth from 

 the reading of the register applied to the reel in sounding with 

 wire. 



Commander Charles D. Sigsbee, United States Navy. 



Although this is only a method, and is represented simply by a plate, 

 attention is called to it because of the great amount of labor saved by 



