Читать книгу The Sea: Its Stirring Story of Adventure, Peril, & Heroism (Vol. 1-4). The History of Sea Voyages, Discovery, Piracy and Maritime Warfare онлайн

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THE CHALLENGER MADE FAST TO ST. PAUL’S ROCKS (SOUTH ATLANTIC).

The observations made for deep-sea temperatures gave some remarkable results. Here, among the icebergs, a band or stratum of water was found, at a depth of eighty to 200 fathoms, colder than the water either above or below it. Take one day as an example: on the 19th of February the surface temperature of the sea-water was 32°; at 100 fathoms it was 29·2°; while at 300 fathoms it had risen to 33°. In the Atlantic, on the eastern side about the tropics, the bottom temperature was found to be very uniform at 35·2°, while it might be broiling hot on the surface. Further south, on the west side of the Atlantic below the equator, the bottom was found to be very nearly three degrees cooler. It is believed that the cold current enters the Atlantic from the Antarctic, and does not rise to within 1,700 fathoms of the surface. These, and many kindred points, belong more properly to another section of this work, to be hereafter discussed.