536 



SUBMARINE CABLE LAYING AND REPAIRING. 



Mr. Schaefer also suggests a 10 ohm subdivided shunt for 

 fault localisations by simultaneous methods. In these methods, 

 such as Kempe's loss of current test, the received current at 

 the distant end of a cable is very feeble, and the shunt proposed 

 would give a range on the combination with the usual type 

 Sullivan galvanometer of about 5 to 40 microamperes per 

 division, suitable for these observations. 



500 

 Position of Break. 



550 



660 



Ohms, 



Fig. 303. — Break Localisation Curve to False Zero (E. Jona). 



The Graphic Representation of Localisation Tests. — Mr. 



E. Jona, in a very instructive article {The Electrician, June 21, 

 1901), showed the advantage, in a break test, of setting out in 

 the form of a curve the various bridge readings in relation to 

 the respective currents employed. From the curve the resis- 

 tances corresponding to any current or ratio of currents which 

 suited the calculation could then ba obtained by simple inspec- 



