Identifier: thalassaessayond00wil (find matches)
Title: Thalassa; an essay on the depth, temperature, and currents of the ocean
Year: 1877 (1870s)
Authors: Wild, John James
Subjects: Ocean
Publisher: London, M. Ward & Co.
Contributing Library: Smithsonian Libraries
Digitizing Sponsor: Smithsonian Libraries

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lat.60° S.—no depths exceeding 2000 fathoms having as yetbeen ascertained beyond these latitudes—the average depth ofthe ocean between these parallels may be estimated at about2500 fathoms, or more roughly at three English miles, and theaverage depth of all seas on the surface of the globe at probablytwo miles. Contrary to the ideas formerly entertained of the enormousdepth of the ocean, the soundings of H.M.S. Challenger,S.M.S. Gazelle, and of the U.S.S. Tuscarora and Gettys-burg, indicate that depths of five miles, or over 4000 fathoms,are but seldom met with, and are as exceptional as heights ofthe same amount on land. The greatest depth ascertained in the Atlantic was found byH.M.S. Challenger, in lat. 19° 41 N., long. 65° 7 W., abouteighty miles north of the island of St. Thomas, in the WestIndies. It is 3875 fathoms, or about four and a-half miles. InMay, 1876, the Gettysburg found 3593 fathoms in lat. 19° 30N., long. 65° 5 W., or only eleven nautical miles south of the
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Depth of the Ocean. 15 Challenger sounding, and 3697 fathoms in lat. 21° 53 N., long.65° 9 W., about 132 nautical miles north of the same sounding,A depth of 3370 fathoms was obtained by the American ship inlat. 25° 47 N., long. 65° o W., which shows that tHe deepestarea in the Atlantic is placed to the northward of the VirginIslands, and extends over 400 miles along the meridian of 65° w. The greatest depth observed in the Indian Ocean wasdiscovered by the Gazelle in May, 1875. Two soundings of3020 and 3010 fathoms were taken in the eastern extremity ofthis ocean between the north-west coast of Australia and theline of islands extending from Java to Timor. The greatest of all depths of which we have reliable evidencewas found by the Challenger on the 23rd March, 1875, in thecomparatively narrow channel which separates the CarolineIslands from the Mariana or Ladrone Islands. This soundingis situated in lat. 11° 24 N., long. 143° 16 E., and amounts to4575 fathoms, or about five

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