Title: Science of the sea. An elementary handbook of practical oceanography for travellers, sailors, and yachtsmen
Year: 1912 (1910s)
Authors: Challenger Society Fowler, G. Herbert (George Herbert), 1861-1940
Subjects: Oceanography Ocean
Publisher: London, John Murray
Contributing Library: Smithsonian Libraries
Digitizing Sponsor: Biodiversity Heritage Library
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t from some important expedition, so that hemay get the literature of the group under control.The choice of the group will depend to some extenton the waters to be traversed, but in this, as in all suchmatters, the Society will be glad to advise. Note.—As it may help the beginner to have standards foropen tow nets suggested to him, one of the writers submits hisown specification, which does not differ greatly from the netsin use generally on expeditions—(i) Net : circumference ofmouth, 5 feet ; circumference at tin, i foot; length, 6 feet ;meshes per linear inch, 62 ; breadth of top and bottom tapes,i£ inches. (2) Cane frame, inside diameter, 18 inches. [(3) STANDARDS 199 Bridles, 2 feet 6 inches long. (4) Length of haul, 20 minutes.(5) Horizons for shallow work, surface, and 25, 50, 75, and 100fathoms, with occasional hauls at 150 fathoms. This writersnew horizontal closing net takes the same silk net as thecane frame, and the results of the two can therefore readilybe compared.
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Fig. 156.—Cestus, or Venuss Girdle. (After Chun.) CHAPTER VITHE SEA FLOOR BY SIR JOHN MURRAY Methods.—The oldest method of sounding was bymeans of the hand-lead, usually 12 to 14 pounds inweight, armed with lard or tallow, to which asample of the bottom adheres, and with a line markedin fathoms and fractions of a fathom. Practicallyall the coasts of the world have been surveyed byinstruments of this kind used from rowing-boats.When attempts were made to sound in 100 or 200fathoms, heavier weights and more carefully preparedhempen lines were employed, and the leads were pro-vided with cups, valves, or snappers, to bring upsamples of the sands, gravels, and muds. Sir JamesClark Ross, during his Antarctic cruise (1839 *01843), made most praiseworthy attempts to soundthe greater depths of the ocean with ordinary soundinglines and heavy weights from small boats. Hesucceeded in recording depths down to 3,600 fathoms,but, although the time each 10O fathoms left the reelwas noted in the u
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