8 



THREE CRUISES OF THE ''BLAKE." 



much smaller tank than is necessary when the axle is retained. 



When a reel containing wire is out of use it is generally kept 



in a tank of oil. A crank is provided for each end of the 



axle. 



The register (B, Fig. 4) is the same as that used by Sir 



William Thomson, and is worked by a screw-thread attached to 



the axle of the reel. The reg- 

 ister evidently does not record 

 fathoms, an inter23olation being 

 necessary in determining, from 

 the reading of the register, the 

 length of wire payed out. It is 

 very handy, however, for keep- 

 ing an approximate account of 

 the wire payed off, so that the 

 correct amount of resistance can 

 be applied to the reel. The cor- 

 rection of the register is easOy 

 found by the method used on 

 board the "Blake." See p. 14. 

 The reeling-in or strain pul- 

 ley (C, D, E, Fig. 4) is com- 

 posed of three separate pulleys, 

 C, D, and ^, — the score E for 

 the wire ; the score C for a con- 

 necting rubber or rope band 

 with the friction score of the 

 reel, if desired; and the score 

 D for an endless rope -band 

 connecting with the hoisting- 

 engine. 



The accumulator is composed 

 of the tubes F, F, F, and C 

 (Figs. 4, 5), containing spiral 



Fig. 5. — Sigsbee Sounding Machine, end 

 view. (Sigsbee.) 



springs (thirty-one inches long, two and a half inches outside 

 diameter, four feet movement for one hundred and fifty pounds 

 strain directly applied), connected with movable cross-head H 

 (Fig. 5) by means of the chain (or wire rope) /, / (Figs. 4, 5), 



