Strait of Magellan.--Climate of the Southern Coasts · 2

[8] With regard to Tierra del Fuego, the results are deduced from the observations of Capt. King (Geographical Journal, 1830), and those taken on board the Beagle. For the Falkland Islands, I am indebted to Capt. Sulivan for the mean of the mean temperature (reduced from careful observations at midnight, 8 A.M., noon, and 8 P.M.) of the three hottest months, viz., December, January, and February. The temperature of Dublin is taken from Barton.

[9] Agueros, Descrip. Hist. de la Prov. de Chiloe, 1791, p. 94.

[10] See the German Translation of this Journal; and for the other facts, Mr. Brown’s Appendix to Flinders’s Voyage.

[11] On the Cordillera of central Chile, I believe the snow-line varies exceedingly in height in different summers. I was assured that during one very dry and long summer, all the snow disappeared from Aconcagua, although it attains the prodigious height of 23,000 feet. It is probable that much of the snow at these great heights is evaporated rather than thawed.

[12] Miers’s Chile, vol. i. p. 415. It is said that the sugar-cane grew at Ingenio, lat. 32 to 33 degs., but not in sufficient quantity to make the manufacture profitable. In the valley of Quillota, south of Ingenio, I saw some large date palm trees.

[13] Bulkeley’s and Cummin’s Faithful Narrative of the Loss of the Wager. The earthquake happened August 25, 1741.

[14] Agueros, Desc. Hist. de Chiloe, p. 227.

[15] Geological Transactions, vol. vi. p. 415.

[16] I have given details (the first, I believe, published) on this subject in the first edition, and in the Appendix to it. I have there shown that the apparent exceptions to the absence of erratic boulders in certain countries, are due to erroneous observations; several statements there given I have since found confirmed by various authors.

[17] Geographical Journal, 1830, pp. 65, 66.

[18] Richardson’s Append. to Back’s Exped., and Humboldt’s Fragm. Asiat., tom. ii. p. 386.

[19] Messrs. Dease and Simpson, in Geograph. Journ., vol. viii. pp. 218 and 220.

[20] Cuvier (Ossemens Fossiles, tom. i. p. 151), from Billing’s Voyage.

[21] In the former edition and Appendix, I have given some facts on the transportal of erratic boulders and icebergs in the Atlantic Ocean. This subject has lately been treated excellently by Mr. Hayes, in the Boston Journal (vol. iv. p. 426). The author does not appear aware of a case published by me (Geographical Journal, vol. ix. p. 528) of a gigantic boulder embedded in an iceberg in the Antarctic Ocean, almost certainly one hundred miles distant from any land, and perhaps much more distant. In the Appendix I have discussed at length the probability (at that time hardly thought of) of icebergs, when stranded, grooving and polishing rocks, like glaciers. This is now a very commonly received opinion; and I cannot still avoid the suspicion that it is applicable even to such cases as that of the Jura. Dr. Richardson has assured me that the icebergs off North America push before them pebbles and sand, and leave the submarine rocky flats quite bare; it is hardly possible to doubt that such ledges must be polished and scored in the direction of the set of the prevailing currents. Since writing that Appendix, I have seen in North Wales (London Phil. Mag., vol. xxi. p. 180) the adjoining action of glaciers and floating icebergs.