178 DISCOVERY REPORTS 



ARRANGEMENTS FOR SCIENTIFIC WORK 



On board the 'William Scoresby', a smaller vessel, arrangements for scientific work 

 are necessarily of a simpler character than in the 'Discovery'. Apart from the main 

 winch there are only two auxiliary deck machines — one of which also drives the Lucas 

 sounding machine — and there is only a single laboratory. 



The Main Winch (Plate XVII, fig. i) was specially constructed to carry three drums 

 of wire rope: two of these are required for the heavy warps used with the otter trawl, 

 and one, placed in the centre, for a long length of light rope employed in plankton 

 investigations. 



The winch is of the horizontal type and was made by the Strath Engineering Works 

 of Aberdeen. The cylinders are of 9 in. diameter and 14 in. stroke, working at the full 

 boiler pressure of 180 lb. to the square inch. The side and centre frames are of cast 

 steel, and clutches, fitted on machined squares, are provided, so that any one drum can 

 be used independently. The three main drums are each 48 in. in diameter and 33 in. 

 between flanges, built up with cast steel hubs and mild steel end plates. The two side 

 drums each hold 1000 fathoms of trawl warp, 2J in. in circumference, while the centre 

 drum carries 3500 fathoms of rope, tapering in circumference from i| to if in. Warping 

 drums are fitted at each end of the main shaft. The piston rods and valve spindles are 

 of manganese bronze, the latter being specially large to resist heavy wear and exposure. 

 Drain cocks, lubricators and other necessary fittings are suitably arranged for service 

 in the Antarctic. The reversing gear is of the link type. An independent brake, lined 

 with wood and operated by screw gear, is fitted to each drum, and hand traversing gear 

 is provided for guiding the wire on to the drums. The whole winch is assembled on 

 a cast-iron bedplate, which is seated on a pitch-pine bed on the fore deck immediately 

 forward of the laboratory. The weight of the winch without wire ropes is about lol tons : 

 with the three drums full of wire rope the total weight is about i8j tons. 



Apart from being a little fierce in its action the winch has proved very satisfactory, 

 giving no trouble in the course of long and continuous service. 



In trawling operations the ropes from the port and starboard drums are led by fair- 

 leads of the usual pattern to the gallows on the port side of the vessel, the arrangement 

 being closely similar to that found on commercial trawlers. The cod-end of the trawl 

 is lifted by a purchase from the main-mast on to the fore deck, where a pound is placed 

 to receive the catch. In plankton operations with horizontal or oblique nets the boom 

 of the main-mast is guyed over towards the port side, and the wire rope from the centre 

 drum is led to a recording sheave slung at its foot. The rope then passes by way of a 

 snatchblock at the head of the boom to the port quarter, and as soon as the nets have 

 been shot, it is triced up in this position. The topping lift of the boom is attached to a 

 large spring placed vertically on the forward side of the mast. By this arrangement, 

 which acts as an accumulator, a certain amount of play is given to the boom and to 

 the rope which it carries. 



