THE CABLE SHIP ON REPAIRS, 293 



These mechanical grips can be used for instantly holding 

 cable at the bows. When cable appears on the grapnel above 

 water, chain stoppers are generally put on on each side, and 

 then the cable cut through at the bight. This takes appreci- 

 able time and the ends may slip through if the stoppering 

 is not properly done. With the mechanical grip one end of a 

 length of chain attached to the grip is made fast inboard, and 

 when the grip is set on the cable and jammed tight the ship 

 heaves in. In the form in Fig. 175 chains can be attached at 

 both ends so that as an extra precaution an ordinary stopper- 

 ing, by means of the outboard chain, can be put on if desired 

 or a second grip can be shackled on and applied to the cable. 



Paying out. — The ship now proceeds to pay out at a 

 speed of four or five knots, the course being in a direct 

 line for the position of the buoy on the other end. In the 

 testing room watch is kept continuously on a spot of light 

 from the galvanometer, which remains stationary so long 

 as the cable leaves the ship in a perfect electrical condition. 

 Should the insulation fail from any cause the galvanometer 

 would instantly show it, and the ship would be stopped. At 

 intervals the shore is communicated with, and the instructions 

 sent by ship are usually a repetition of " Free one hour, then 

 look out," as paying-out proceeds. The battery on board being 

 connected to cable through galvanometer, only the usuai 

 small current through the insulation can pass while the end 

 on shore is free, and this deflection on the instrument remains 

 constant, unless a fault is payed out. 



In the tank careful precautions are taken to prevent the cable 

 " taking charge." Men are stationed below, inside the tank, 

 who see that not more than one turn at a time is lifted, and that 

 the bights between adjacent flakes are properly guided out, so as 

 to avoid kinks forming. In large tanks, a crinoline is used for 

 guiding cable as it is uncoiled. This is a set of rings braced 

 together as shown in Fig. 177. The crinoline is used partly to 

 guide the cable toward the centre of the tank from the moment 

 it is lifted in paying out and partly to hinder by friction 

 the overrunning of the cable, which if not flexible would rise 

 and form into a " cartwheel," which might produce a kink. 

 The crinoline consists of a sat of three or four iron rings 



