CHAP. XVIII.] DEEP-SEA SOUNDINGS 401 



machine is fixed ; and never let the ship get more than two 

 points off the wind unless a weather tide necessitates it. 



Always endeavour to keep the position by small changes 

 of speed and helm, avoiding high speed. This demands the 

 closest watch, and the moment the ^vire is seen to be getting 

 out of the vertical, apply the brake and steam her up with the 

 helm in the necessary position. Bear in mind that the helm is 

 of little use, even with slight headway, unless the screw is 

 working. 



If you have failed to catch her in time, act decisively Avith 

 engines and helm before matters get too bad, using high speed 

 if necessary. A few quick revolutions of the screw Avith helm 

 hard over is the best plan, checking the headway thus unavoid- 

 ably given by a back turn when she has sufficient swing on, 

 remembering that going astern always causes the sliip's head 

 to fall off from the wind, but to a less extent if the wind is on 

 that side to which the ship's head naturally turns in a calm on 

 reversing the engines. 



The worst position is when the Avire gets under the bottom, 

 as it may catch the copper, and everything must be done to 

 prevent this occurring. It will generally happen from alloAving 

 the wind to get on the AArrong bow. In such a case it Avill 

 probably be necessary to steam her rapidly round till the aa ind 

 is on the right bow, and then let her drop doAvn until the AA-ire 

 is again clear. 



Should the wire foul the copper, or, as it may do, the gang- 

 way Avire used for serial temperatures, it is sometimes possible 

 to clear it by getting out the lower boom and using long hook 

 ropes of ordinary sounding line with AAeighted smooth hooks. 



A surface current across the wind complicates matters con- 

 siderably. In order to get an up and doAvn sounding, the ship 

 must be moved against the current, and the wind must then 

 be more or less on the beam ; with a a\ eatherly current the 

 wind may be nearly aft. Under such conditions it requires 

 a practised eye and hand to manage the ship. 



It must be understood that unless the wire is nearly up and 

 down, it may be very difficult to say Avhen the bottom is reached, 

 and the depths as given by the wire out, Avill not be accurate. 

 If Avire is run out after the lead has reached the bottom, kinks 

 wdll result, and the wire Avill part. 



26 



