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BELL SySTE^f TECHNICAL JOURNAL 



VII. LOADINC; FOR SUHMARIXE C'aHLKS 



Coil Loading. The special problem of applying coil loading to 

 submarine cables is a mechanical one, rather than one concerning 

 ihe principles of loading. The situation in the United States is such 

 that onh" a few coil loaded submarine cables ha\e been required ; this, 

 of course, does not refer to the considerable number of instances 

 where the submarine cables are so short that ordinary types of coils 

 installed at the terminals satisfy the transmission requirements. 



To date there have been installed in the United States a total of 

 five cables having submarine coil loading; details of which are given in 

 Table XVHI. 



TABLE XVIII 

 Coil Loaded Submarine Cables 



The Raritan Bay cables each ha\e 37 quads loaded at five points, 

 111 coils at each point, constituting the largest installation of sub- 

 marine coil loading in the world. The depth of water in which these 

 cables are installed is about 35 feet. 



In each of the above instances, dry core paper cables were used. 

 The design of the coil was made to fit the special designs required for 

 the submarine loading pots. The case design was such as to furnish 

 complete protection of the coils against moisture penetration and ade- 

 quate mechanical strength for taking up the tension in the cable. In 

 installing the cables, the procedure was to splice the loading coil cases 

 into the cable while the cable was coiled on a barge, and then lay the 

 cable and coils as a continuous operation. The service record of these 



