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Show 294 '£1ERRA DEL FUEGO. June, 1834. consequence of the elevation of the land, of which proofs have lately been brought to light.* In a former part of this volume, I have endeavoured to prove, that as far as regards the quantity of food, there is no difficulty in supposing that these large quadrupeds inhabited sterile regions, producing but a scanty vegetation. With respect to temperature, the woolly covering both of the elephant and the rhinoceros seems at once to render it at least probable (although it has been argued that some animals living in the hottest regions are thickly clothed) that they were fitted for a cold climate. I suppose no reason can be assigned why, during a former epoch, when the pachydermata abounded over the greater part of the world, some species should not have been fitted for the northern regions, precisely as now happens with deer and several other animals.t If, then, we believe that the climate of Siberia, anteriorly to the physical changes above alluded to, had some resemblance with that of the southern hemisphere at the present day-a circumstance which harmonizes well with other facts,t as I think has ' ~ Wrangel's Voyage in the Icy Sea in the years 1821, 1822, and 1823. Edited by Professor Parrot, of'Dorpat, Berlin, 1826. . t D:. Flemin~ first brou_ght this notion forward in two papers published m the Edmburgh Philosoph. Journ. (April, 1829, and Jan. 1830). He adduces the case of allied species of the bear fox hare and 1· · , • ' ' , OX, !Vmg under widely different climates. t Since writing the above, I have been much interested by reading an . account by Professor Esmark, which proves that formerly, glaciers in Norway descended to a lower altitude than at present; and therefore, that t~ey came down to tl~e Ie:el of the se.a in a lower latitude. This, acc.ordmg to ~enerally-received Ideas, would mdicate a colder climate, and so It was con~1dered to do by Professor Esmark ; for he argues from it in fa~ou~ of Whiston's hypothesis, that the " earth in its aphelion was covered With Ice and snow." Professor Esmark describes a glacier-dike in lat 58° 57' , as " I ym. g cI ose to the level of the sea, in a district, where 'y ou find. only~. few heaps of pe:pe~ual snow in the hollows of the mountains." He says, Not only the d1ke Itself, but the whole horizontal surface, exhibits proofs that there has been a glacier here, for the plain exactly resembles June, 1834. ANiMALS PRESERVED IN ICE. 295 been shown by the imaginary case, when we transported existing phenomena from one to the other hemisphere,-the following conclusions may be deduced as probable : First, that the degree of cold formerly was not excessive; secondly, that snow did not for a long time together cover the ground (such not being the case at the extreme parts 55°-56° of S. America) ; thirdly, that the vegetation partook of a more tropical character than it now does in the same latitudes ; and lastly, that at but a short distance to the northward of the country thus circumstanced (even not so far as where Pallas found the entire rhinoceros), the soil might be perpetually congealed : so that if the carcass of any animal should once be buried a few feet beneath the surface, it would be preserved for centuries. Both Humboldt* and Lyell have remarked, that at the present day, the bodies of any animals, wandering beyond the line of perpetual congelation which extends as far south as 62°, if once embedded by any accident a few feet beneath the surface, would be preserved for an indefinite length of time : the same would happen with carcasses drifted by the rivers ; and by such means the extinct mammalia may have been entombed. There is only one small step wanting, as it appears to me, and the whole problem would be solved with a degree of simplicity very striking, compared with the several theories :first invented. From the account given by those which I found adjoining the glaciers presently existing between Londfiord and Lomb." (See Ed. New Phil. Journal, p. 117, October 1826.) These facts afford a very strong and admirable confirmation of the view, that the climate of Europe has been gradually changing, from a character resembling that of the southern hemisphere, to its present condition. For on this hypothesis, we might have anticipated, that proofs would have been discovered, that glaciers formerly descended to a lower altitude than they now do ; and yet, that the organic remains of that epoch, instead of a former period of refrigeration, would have indicated a climate of a more tropical character ;-a conclusion, which may be de duced from plain geological evidence. ., See Humboldt, Fragmens Asiatiques, vol. ii., pp. 385-395. |