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coil terminals, after which the skeleton unit consisting of the coils 

 and stub cable with case cover attached, is picked up with suitable 

 tackle, and the coil unit inserted in the case. Fig. 17 illustrates this 

 stage of the assembly. The case is sub.sequently filled with moisture- 

 proof compound and sealed in the usual manner. 



Fig. 17 — Assembly of 300-coil case 



Lowering loading coils into case after coil spindles have been"mounted on frame and 



coil terminals spliced to stub cable conductors 



InstnUation Features. In general, the exchange area cables on 

 which loading is reciuired are run in underground ducts and conse- 

 quently the great bulk of the exchange area loading is installed in 

 underground vaults. Fig. 18 shows a typical loading installation 

 in a ••double-deck" vault in New York City. The loading coil cases 



