220 SUBMARINE CABLE LAYING AND EEPAIEIXG-. 



cut through on the grapnel with a hack-saw, as there is rarely 

 sufficient slack to haul the bight inboard, and it is olten neces- 

 sary, after cutting the cable, to slack out a good deal on one 

 side before the other can be heaved on board. 



The ends are then stripped, and the copper conductors con- 

 nected on by binding screws to a pair of insulated wires from 

 the bows to the testing- room. These are numbered 1 and 2, 

 and the stations on shore to which the cable-ends belong are 

 seen by the way the cable is bearing, so that it is known in the 

 testing-room which station is on each wire. The act of cutting 

 the cable generally produces currents or disturbs the earth or 

 polarisation currents in such a manner as to produce " kicks " 

 or jerky signals on the mirror instruments on shore, so that 

 some intimation of the ship having got the cable is generally 

 to be noticed before she actually calls up. 



From the moment the cable is at the bows the busiest time 

 for the chief electrician and his assistant begins. He may be 

 occupied but a couple of days before completing the repairs, or 

 he may be a week or more. There is no telling till the first 

 test is taken and picking up commences. The cable may be 

 buried in coral and keep breaking, or the fault may be a very 

 difficult one to localise, and be really much further off than it 

 appears. At all events, right through the job it is continuous 

 work day and night, with frequent testing and record-keeping 

 of lengths picked up and paid out, and messages to be received 

 and sent to keep the head office informed of the ship's move- 

 ments. It may be said, as indeed is the case, and necessarily 

 so, that the ship's movements are under the chief electrician's 

 orders from the moment the cable is at the bows ; and the 

 responsibility is one of no small importance. 



No time has now to be lost to find out by tests on the two 

 ends towards which direction the fault lies, and to acquaint the 

 officer on watch which end is to be buoyed. To do this the 

 distant ends on shore must in turn be " freed," Each end in 

 the testing-room is then joined up in turn to the speaking- 

 mirror connections, the station called up and asked to " free 

 five minutes " ; and as soon as the reply from shore comes, 

 "OK, done," the end is instantly put over to the testing 

 connections and the test taken. The test is simply the passing 

 of a current direct through a marine reflecting galvanometer 



