VII. Report to the hydrographer of the admiralty on the voyage of the 'Challenger' from the Falkland Island to monte video, and a position in lat. 32º24'S., long. 13º5'W

Abstract

Sir,—I have the honour to report that we left Stanley Harbour in East-Falkland Island for Monte Video on the afternoon of the 6th of February, and on the 8th we sounded in lat. 48° 37' S., long. 55° 17' W., about 200 miles to the N. E. of Stanley, in a depth of 1035 fathoms. The trawl was lowered, but it was unfortunately carried away, after the weights, which were at a distance of 300 fathoms in advance of the trawl, had been brought in board. The rope looked much chafed, as if it had been ground against rocks. The sounding-machine brought up no sample of the bottom; but a tow-net attached to the dredge-rope at the weights con­tained a little gravel and one or two small organisms. The bottom-temperature was 1°·7 C. The following day was fine, with light uncertain winds; on the 10th it was blowing half a gale and the sea was running too high for sounding-operations. On the 11th the weather was fine, the wind becoming more moderate towards noon; at 10 a.m. we sounded and put down the trawl in 2040 fathoms, with a bottom of bluish mud containing many Globigerinæ ,and a bottom-temperature of +0°·3 C. The position of the sounding was lat. 42° 32' S., long. 56° 27' W., about 200 miles to the eastward of Valdes Peninsula. Temperature-soundings were taken down to 1500 fathoms (Curve 318, Plate 27). This sounding gives a singularly rapid fall from 14º·2 on the surface to 2° C. at 125 fathoms; the edge of the Ant­arctic indraught appeared to be pushed up against the American shore by the western border of the southern branch of the reflux of the equa­torial current, as the Labrador current is banked up by its northern branch, the result being no doubt increased in both cases by the flinging up of the polar water against the western land-barrier on account of its low initial velocity.