DIRECTIONS roi; TOUIJISTS. 277 



a w'firlil i)f llmugiit must liave ln'i'ii expeiuleil in the construction 

 of sucli an instrument, wliicli with the little wire wliicli unites 

 two hemi-plieres, has made the cry>;tal ilome of the Atlantic a 

 whispering gallery between the Old "World and the New. 

 HOW BREAKS AUK DETECTKD. 

 Another wonderful instrument shown to the visitor is the 

 delicate machine In whicli a hreak or flaw in the cahle is ([uickly 

 located, and accurately determined within a lew yards. Tin' 

 following explanation will convey some idea of the method hy 

 wdiich this \\(jnderful i'eat is peri'ormed : "The whole electric 

 potency of the cahle, when fully charged is known ; and the 

 same can be (inickly ascertained of the two parts created liy a 

 break. A delicate instrument, adjusted to the nicest tractions,, 

 discloses the electric units or "ohms" in ea(di part ; and as the 

 number of ohms to the mile is known, the nuh's ami fractions of 

 miles iu both parts can lie found ont at each end of the cable. 

 In the case of a clean lueak the locating of it takes about fifteen 

 minutes. But a very angular break, or a Haw makes perturba- 

 tions of the measurement wliich it, now and then, takes some' 

 hours to rectify." 



FEAT OF THE S. S. " MINIA." 



Almost as wonderfu is the process Ijy which the broken ends 

 of the cable are ]>icketl up with ease and certainty and the injury 

 repaired. The famous cable sliip Minia, Captain Ti-ott, a few 

 j'ears ago, picked ii]) an injured cable of the Anglo-American 

 Company, without trouble, at a depth of two and a quarter miles- 

 near the middle of the Atlantic. 



NEAV CABLE OF 1894. 



Wonderful im])rovements in the manufacture of the modern 

 cable have been made ; and each new cable seems to surjtass its 

 2:)redecessors. The dujjlex system of sending or receiving messages 

 doubles the capacity of every new cable that is laid. The work- 

 ing life of a cable is now about ^0 years. While this page is 

 going through the press, the laying of a new cable by the Anglo- 

 American Company has connnenced at Heart's Content. It in 



