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SUBMARINE CABLE LAYING AND REPAIRING. 



It greatly facilitates the work to have three sheaves available, 

 one for an extra line from ship as in lowering a splice, or one 

 for grapnel rope and the other two for stopper lines. And, 

 considering the superiority of cast steel in this class of 

 machinery, it is not surprising that every opportunity of 

 economising space and weight by its use should be taken. 

 The triple bow sheaves, illustrated in Figs. 185 and 186, have 

 been designed by Mr. Percy L. Isaac for the Eastern Telegraph 

 Company, and are now supplanting the older forms in this 

 Company's ships. The whole is fitted in a cast-steel frame 

 bolted to the deck girders, and takes up less room and is lighter 



Fig. 186. — Isaac's Triple Bow Sheaves. 



for the same strength than the original double sheaves in iron. 

 It is usual to fit "whiskers" or cheeks between the sheaves as 

 shown in Fig. 189. The use of these is to prevent the grapnel 

 rope jumping over to the next sheave when pulled sideways 

 by the strain below. 



Final Splice and Completion of Repair. — The end of 

 cable just unmoored from buoy and secured on board is now 

 connected up to testing-room for the purpose of communicating 

 with the shore on that side. It will be remembered that at the 

 time of first cutting in, before buoying, the electrician in- 

 structed this end to keep watch day and night after a certain 



