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Show TIERRA DEL FUEGO. June, 1834. peaks in the snow-clad mnge is under 7000 feet, it is evident that the height of the snow-line cannot at most much exceed 6000 feet. As this is a point of interest, I shall mention a few other circumstances, by which I think we may come to a nearly definite conclusion. On February 2d (1835) I obtained the last view of the Cordillera ; on that day the lower line of the snow descended some way (so as to form a considerable angle with the summit, when viewed from a distance of 61 miles) on the mountain south of Osorno (lat. 41° 20'), which stands by itself, and has a height of 5607 feet. Since arriving in England I have received a letter from Mr. Douglas in Chiloe, who, describing some volcanic phenomena, accidentally mentions the snow-line. He says, on February 20th (same year), on the volcano of Minchinmadiva (lat. 42° 48'), which has an elevation of 7046 feet, lava was ejected from a crater "just above the verge of the snow." Again, on February 27th, he alludes to the summit of the Corcovado (7510 feet) being covered with snow, as was Yntales* (6725 feet) in lat. 43° 30'. Again Mr. Douglas, speaking of the Corcovado, says, " On the 16th of March the snow appeared to cover one-fifth of its (vis ible) perpendicular height." By this date the snow-line must have attained its greatest height (if, indeed, fresh snow had not fallen); and, as the Corcovado rises in an unbroken slope close to the sea, the proportion covered by sno'; might be judged of, with some degree of accuracy. The height of the Corcovado (7510 feet) was obtained by three angular measurements, made by the officers on the survey, and the mean nearly agreed with the three separate results. ~eflecting on all these circumstances, we may conclude with perfect safety, that the limit of perpetual snow, between the latitudes 41° and 43°, cannot much, if at all, exceed 6000 feet. Proceeding northward along the Cordillera we find a very • On January 15th, Yntales, seen from the Northern Chonos Islands, was entirely covered by snow. une, 1834. HEIGHT OF SNOW·LINE. 277 different condition of things. In the pass of the Portillo (to the southward of 33°) Dr. Gillies determined barometrically the height of the double range ; and he found the two ridges to be respectively 13,210 and 14,365 feet. On March 21st and 22d (1835), shortly before fresh snow fell, I crossed these mountains,* and although there were large masses of snow, there were much greater spaces at some height on each side uncovered. Dr. Gilliest says, "the summit (of the volcano of Peuquenes) is generallyt covered with snow, and its elevation cannot be less than 15,000 above the level of the sea." From these statements, compared with my observations, the snow-line when I crossed certainly was considerably above 14,365,-we may assume 15,000 as about the limit. From the results obtained by Humboldt, Pentland, Gillies, and King, we are enabled to draw up the following table of the extraordinary range of the snow-line on the Cordillera of South America : Latitude. Height in feet of Snow· line. Observer. Equatorial region : } 15,748 Humboldt. Mean result. Bolivia, } 17,000 Pentland.§ Lat. 160-180 S. Central Chile, } { 14,500 to Gillies. Lat. 33° S. 15,000 Chiloe, } 6,000 Officers of the Beagle. Lat. 41°-43° S. Tierra del :Fuego, } { 3,500 to King.JI 54° s. 4,000 • I crossed the Uspallata Pass on April 5th. The height, as given by Mr. Pentland (Geographical Journal), is 12,454. In the ravines there were some inconsiderable patches of snow, but the general surface was quite bare. t The Edinburgh Journal of Natural and Geographical Science, August, 1830, p. 316. . :j: I have reason to suspect that the snow-line in Chile is subJect to ex- |