decided to lay the cable from the shore outward. This obviated the 

 possibility of not having enough cable to reach shore, simplified the 

 navigational procedure and enabled continuous monitoring of the hydro- 

 phones from shore during the laying operation. 



The cable was wound on a steel reel six feet in diameter and 

 four feet wide, that was mounted on two steel tripods. The deep and 

 shallow hydrophones and associated lengths of distribution wire were 

 assembled and wound on the reel. The overlapping portions of the two 

 lengths were taped together. The armored cable was connected to the 

 pair of distribution wires and wound over them. All connections were 

 made and the assembly was completed and tested so that the laying could 

 be carried out as a continuous operation. 



Splicing the distribution wires to the armored cable was 

 considered to be the most vulnerable of the assembly operations. When 

 a splice was completed, there was no available way of telling beforehand, 

 whether or not it would be short circuited from sea water seepage. The 

 conductors were joined by means of crimped sleeves and wrapped with both 

 polyethylene tape and D.R. tape. Such a splice, called a wet splice, is 

 exposed to the sea water but is relieved of tension by the splice case. 

 Also, there was no available way of testing for failure of the splice 

 case to carry the tension of the armor wires. 



The reel and cable assembly, weighing about 6000 pounds, was 

 mounted on the after deck of the R/V LORD KELVIN, a vessel chartered from 

 the Marine Acoustical Services, Inc., Miami. It is a converted subchaser 

 112 feet long, with adequate deck space for a reel, twin screws, and a 

 relatively shallow draft of 6.25 feet. 



(b) Cable Laying 



With the R/V LORD KELVIN anchored a few hundred feet from the 

 shore line of the Lerner Laboratory property, the end of the four conductor 

 armored cable was taken ashore with the aid of a light line and a small 

 boat. After the cable was secured, audio monitoring circuits connected to 

 each pair of conductors indicated that both hydrophones were operative. 

 Paying cable over her stem, the R/V LORD KELVIN then proceeded toward a 

 marker buoy indicating the desired location for the shallow hydrophone. 

 By idling the engines and braking the reel, some control over cable pay- 

 out could be maintained. It was desired to lay the heavy cable with a 

 slack factor of 10% and the light distribution wire with a factor of 25%. 

 With the aid of footage marks on the cable and a knowledge of the ships 

 position, this was accomplished approximately. 



The shallow hydrophone was released about one mile from shore 

 at a marker buoy and the deep hydrophone was released a mile farther out. 

 The hydrophones were monitored throughout the operation and it was reported 

 that six minutes were required for the deep hydrophone to fall 1200 feet 

 from the surface to the bottom. 



On the day after the laying was completed, the cable was viewed 



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