1915] Michael, ef al.: Hiidrographic Records of Scripps Institution fl 



These three engines and the drum are in the engine room. The 

 drum is built in two sections, the larger of which accommodates 2200 

 meters of %-inch hemp-steel cable for dredging and other heavy work, 

 while the smaller accommodates 2000 meters of 3 mm. 28-strand gal- 

 vanized wire for operating the lighter apparatus. In addition, a 

 patent Thompson sounding machine, supplied with 2200 meters of 

 %o nim. piano wire, is located aft of the naturalist's hou.se and ar- 

 ranged so as to be run by a friction wheel on the flywheel of the main 

 hoisting engine. 



All scientific work requiring engine power is done aft. The 

 sounding-wire is paid out on the port side and is independent of the 

 collecting gear, so that soundings may be taken while other work is in 

 progress. The collecting cables are passed from the drum through a 

 runway onto the deck, over a recording meter-wheel, thence to the 

 boom of the mizzenmast. and finally over the stern to the water line. 

 This arrangement has the advantage of bringing together the scientific 

 gear and the naturalist's quarters on the rear deck where there is most 

 available space. Nearly all the work is done while the vessel is adrift, 

 or at a standstill. 



2. THE COLLECTIXG APPARATUS 



(a) The surface nets. — These are all simple conical tow-nets con- 

 sisting of a bronze rim to which is attached a head-piece of impervious 

 cloth, like butcher's linen or canvas. This head-piece serves as a sup- 

 port and means of attachment for the netting proper, which may be 

 of a variety of meshes. The upper end of the netting is securely 

 sewed onto the head-piece and the lower end onto a foot-piece con- 

 sisting of similar impervious cloth, to which the net bucket is attached. 

 The nature of the bucket varies somewhat with the size of the net, 

 bronze buckets being used with larger ones (000. and 000 c) while an 

 ordinary four-ounce pomade bottle has proven the most satisfactory 

 for the smaller nets. To provide a proper .support for the netting, 

 three ropes attached to the rim at equal distances from each other are 

 carried backward and attached to the bucket, and also forward for 

 about three feet where they are brought together and tied. 



It is usually customary to operate three surface nets at the same 

 time. One of the larger nets (000 or 000 c) is fastened to the end of 

 a suitable rope about 200 feet long and to its rim is attached an air- 

 tight five-gallon can or carboy to serve as a float. The net is then 



