The First Atlantic Cables 



Minute as the current is which suffices for 

 cable telegraphy, it is essential that the metallic 

 circuit be not only unbroken, but unimpaired, 

 throughout. No part of his duty has more 

 severely taxed the resources of the electrician 

 than to discover the breaks and leaks in his ocean 

 cables. One of his methods is to pour electricity 

 as it were, into a broken wire, much as if it were 

 a narrow tube, and estimate the length of the 

 wire (and consequently the distance from shore 

 to the defect or break) by the quantity of current 

 required to fill it. 



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