THE LAYING OF SUBMARINE CABLES. 



167 



in as required (Fig. 83), without in any way altering the 

 Willoughby Smith connections. Should a fault occur in the 

 submerged portion, ship's balance on the slides is at once 

 thrown out and shore's galvanometer deflection falls, so that 



SHIP R 



SHORE 



cb c5~ 



- — I - T - Fault 



n 





Ki 



Slides 



■\J\r4 

 10 000 



Lft 



H|ljlil|l|- 



© 



CX3 



Megohm X 

 (Selenium Bar.) 



Fig. 83. — Herbert Taylor's Test for Localising Fault paid out while laying. 



both ends are immediately aware of the fact. The potentials 

 are distributed as in Fig. 84, the potentials P and p being 

 measured on board and p-^^ on shore. The ship then obtains 

 a fresh balance, say of s divisions, equivalent to the potential 



Fig. 84. 



SHORE. 



p, and then changes commutator plug over to connect the 

 standard cell to slides. As the zero of the slides is at the 

 battery end, the readings must be subtracted from 10,000. 

 Say the reading with a standard cell of e volts is n divisions. 



