580 FISHERIES OF THE UNITED STATES. [68] 



APPLIANCES FOE DEEP-SEA SOUNDING. 



Sigsbee's Deep-Sea Sounding Machine, for use with piano-forte wire, on the 

 principle of Sir William Thomson. Eepresented by a model. 



Commander Charles D. Sigsbee, United States Navy. 



In deep-sea sounding with wire, the submerged weights provide a 

 moving force for the sounding-reel containing the coil of wire. The 

 weight of the submerged wire, and of all submerged accessories except- 

 ing the sinker, is overbalanced at discretion by means of a friction-line 

 enwrapping a portion of the reel. Thus the motion of the reel is con- 

 tinued by means of the sinker and controlled by the frictional balance 

 or brake until bottom is reached, when, the weight of the sinker ceas- 

 ing to act, and the remaining submerged weights being overbalanced 

 by the brake, the reel stops automatically. To Sir William Thomson 

 is due the credit of having solved the problem of sounding ocean depths 

 with wire. 



To Tceep the wire constantly under tension is the prime essential, since 

 a failure to maintain this condition will permit the wire to fly from the 

 reel during the motions of the vessel in a seaway. To avoid the loss of 

 time due to accidents or unnecessary delays is of importance in view of 

 the expense attending the maintenance of any organization for deep- 

 sea operations. In the Sigsbee machine every convenience and safe- 

 guard suggested by long experience has been applied, in order to econo- 

 mize time by rapidity of work, by lessening the probability of accident, 

 and by making soundings practicable in any weather during which the 

 vessel can be maneuvered. Several thousand soundings have been 

 taken with the machine, in nearly all conditions of wind, weather, and 

 current, much of the work having been done in moderate gales ; but 

 perhaps the most severe test was that made by Commander Bartlett in 

 the steamer Blake. The Blake (350 tons) was hove to in a severe gale 

 in the swift current of the Gulf Stream, in which condition she got bot- 

 tom in 2,400 fathoms, and reeled in by steam without loss. Becently 

 the Blake sounded with the same machine in 4,561 fathoms (over 5 

 miles), reeling in by steam and getting a specimen of the bottom de- 

 posit. The general custom in using the machine has been to employ a 

 35-pound lead and haul it back in depths not exceeding 1,000 fathoms, 

 and in greater depths to use a 60-pound shot of cast-iron, detaching it 

 on bottom. In all cases the wire has been reeled in by steam. A num- 

 ber of the machines are now in use by Government organizations in the 

 Uuited States and Europe. 



A complete description of the machine and its operation is given in 

 Sigsbee's Deep-Sea Sounding and Dredging, published by the United 

 States Coast and Geodetic Survey in 1880, and again in 1882. The last 

 edition contains a supplement, showing the latest improvements and 

 the way in which the machine is folded for transportation or stowage 



