Sidor som bilder
PDF
ePub

had been prolonged still farther, and the land had been of moderate elevation, it is very probable that they might have extended their range to a greater distance from the tropics. Now, if the Indian tiger can range in our own times to the southern borders of Siberia, or skirt the snows of the Himalaya, we may easily imagine that large species of the same genus may once have inhabited our temperate climates. The mammoth (E. primigenius), already alluded to as occurring fossil in England, was decidedly different from the two existing species of elephants, one of which is limited to Asia, south of the 31° of N. lat., the other to Africa, where it extends, as before stated, as far south as the Cape of Good Hope. The bones of the great fossil species are very widely spread over Europe and North America; but are nowhere in such profusion as in Siberia, particularly near the shores of the frozen ocean. Are we, then, to conclude that this animal preferred a polar climate? If so, by what food was it sustained, and why does it not still survive near the arctic circle : Pallas and other writers describe the bones of the mammoth as abounding throughout all the Lowland of Siberia, stretching in a direction west and east, from the borders of Europe to the extreme point nearest America, and south and north, from the base of the mountains of central Asia to the shores of the Arctic sea. (See Map, fig. 2, p. 104.) Within this space, scarcely inferior in area to the whole of Europe, fossil ivory has been collected almost every where, on the banks of the Irtish, Oby, Yenesei, Lena, and other rivers. The elephantine remains do not occur in the marshes and low plains, but where the banks of the rivers present lofty precipices of sand and clay; from which circumstance Pallas very justly inferred that, if sections could be obtained, similar bones might be found in all the elevated lands intervening between the great rivers. Strahlenberg, indeed, had stated, before the time of Pallas, that wherever any of the great rivers overflowed and cut out fresh channels during floods, more fossil remains of the same kind were invariably disclosed. As to the position of the bones, Pallas found them in some places imbedded together with marine remains; in others, simply with fossil wood, or lignite, such, as he says, might have been derived from carbonized peat. On the banks of the Yenesei, below the city of Krasnojarsk, in lat. 56°, he observed grinders, and bones of elephants, in strata of yellow and red loam, alternating with course sand and gravel, in which was also much petrified wood of the willow and other trees. Neither here nor in the neighbouring country were there any marine shells, but merely layers of black coal.” But grinders of the mammoth were collected much farther down the same river, near the sea, in lat. 70°, mixed with marine petrifactions.t Many other places in Siberia are cited by Pallas, where

* Pallas, Reise in Russ. Reiche, pp. 409, 410. f Nov. Com. Petrop. vol. 17, p. 584.

[merged small][ocr errors][ocr errors]

Map showing the course of the Siberian rivers from south to north, from temperate to arctic regions, in the country where the fossil bones of the Mammoth abound. sea-shells and fishes' teeth accompany the bones of the mammoth, rhinoceros, and Siberian buffalo, or bison (Bos priscus). But it is not on the Oby nor the Yenesei, but on the Lena, farther to the east, where, in the same parallels of latitude, the cold is far more intense, that fossil remains have been found in the most wonderful state of preservation. In 1772, Pallas obtained from Wiljuiskoi, in lat. 64°, from the banks of the Wiljui, a tributary of the Lena, the carcass of a rhinoceros (R. tichorhinus), taken from the sand, in which it must have remained congealed for ages, the soil of that region being always frozen to within a slight depth of the surface. This carcass was compared to a natural mummy, and emitted an odour like putrid flesh, part of the skin being still covered with black and gray hairs. So great, indeed, was the quantity of hair on the foot and head conveyed to St. Petersburg, that Pallas asked whether the rhinoceros of the Lena might not have been an inhabitant of the temperate regions of middle Asia, its clothing being so much warmer than that of the African rhinoceros.” After more than thirty years, the entire carcass of a mammoth (or extinct species of elephant) was obtained in 1803, by Mr. Adams, much farther to the north. It fell from a mass of ice, in which it had been encased, on the banks of the Lena, in lat. 70°; and so persectly had the soft parts of the carcass been preserved, that the flesh, as it lay, was devoured by wolves and bears. This skeleton is still in the museum of St. Petersburg, the head retaining its integument and many of the ligaments entire. The skin of the animal was covered, first, with black bristles, thicker than horse hair, from twelve to sixteen inches in length; secondly, with hair of a reddish brown colour, about four inches long; and thirdly, with wool of the same colour as the hair, about an inch in length. Of the fur, upwards of thirty pounds weight were gathered from the wet sand bank. The individual was nine feet high and sixteen feet long, without reckoning the large curved tusks; a size rarely surpassed by the largest living male elephants.f It is evident, then, that the mammoth, instead of being naked, like the living Indian and African elephants, was enveloped in a thick shaggy covering of fur, probably as impenetrable to rain and cold as that of the musk ox. The species may have been fitted by nature to withstand the vicissitudes of a northern climate; and it is certain that, from the moment when the carcasses, both of the rhinoceros and elephant, above described, were buried in Siberia, in latitudes 64° and 70° N., the soil must have remained frozen, and the atmosphere nearly as cold as at this day. So, fresh is the ivory throughout northern Russia, that, according to Tilesius, thousands of fossil tusks have been collected and used in turning; yet others are still procured and sold in great plenty. He declares his belief that the bones still left in northern Russia must greatly exceed in number all the elephants now living on the globe. We are as yet ignorant of the entire geographical range of the mammoth ; but its remains have recently been collected from cliffs of frozen mud and ice on the east side of Behring's Straits, in Eschscholtz's Bay, in Russian America, lat. 66° N. As the cliffs waste away by the thawing of the ice, tusks and bones fall out, and a strong odour of animal matter is exhaled from the mud.” On considering all the facts above enumerated, it seems reasonable to imagine that a large region in central Asia, including, perhaps, the southern half of Siberia, enjoyed, at no very remote period in the earth's history, a temperate climate, sufficiently mild to afford food for large herds of elephants and rhinoceroses, of species distinct from those now living. At the time to which these speculations refer, the Lowland of Siberia was probably less extensive towards the north than it is now; but the existing rivers, though of inferior length, may have flowed from south to north, as at present, and, during inundations, may have swept the carcasses of drowned animals into lakes, or the sea, as do the Nile, Ganges, and other rivers in our own time.f In Siberia all the principal rivers are liable, like the Mackenzie, in North America, to remarkable floods, in consequence of flowing in a direction from south to north; for they are filled with running water in their upper course when completely frozen over for several hundred miles

[graphic]
[graphic]

* Nov. Com. Petrop. vol. 17, p. 591.

t Journal du Nord, St. Petersburg, 1807.

; Fleming, Ed. New Phil. Journ., No. xii. p. 285.

Bishop Heber informs us (Narr. of a Journey through the Upper Provinces of India, vol. ii. p. 166—219), that in the lower range of the Himalaya mountains, in the north-eastern borders of the Delhi territory, between lat. 29° and 30°, he saw an Indian elephant of a small size, covered with shaggy hair. But this variety must be exceedingly rare; for Mr. Royle (late superintendant of the East India Company's Botanic Garden at Saharunpore) has assured me, that being in India when Heber's Journal appeared, and having never seen or heard of such elephants, he

Vol. I.-O.

made the strictest inquiries respecting the fact, and was never able to obtain any evidence in corroboration. Mr. Royle resided at Saharunpore, lat. 30° N. upon the extreme northern limit of the range of the elephant. Mr. Everest also declares that he has been equally unsuccessful in finding any one aware of the existence of such a variety or breed of the animal, though one solitary individual was mentioned to him as having been seen at Delhi, with a good deal of long hair upon it. The greatest elevation, says Mr. E., at which the wild elephant is found in the mountains to the north of Bengal, is at a place called Nahun, about 4000 feet above the level of the sea, and in the 31st degree of N. lat., where the mean yearly temperature may be about 64° Farenheit, and the difference between winter and summer very great, equal to about 36° F., the month of January averaging 45°, and June, the hottest month, 81°F. (Everest on Climate of Foss. Eleph., Journ. of Asiat. Soc., No. 25, p. 21.) * See Dr. Buckland's description of these bones, Appen. to Beechey's Voy. f See Book iii. chaps. Xv. and xvi.

near their mouths. (See Map, p. 104.) Here they remain blocked up by ice for six months in every year, and the descending waters, finding no open channel, rush over the ice, often changing their direction, and sweeping along forests and prodigious quantities of soil and gravel mixed with ice. The rivers of this great country are among the largest in the world, the Yenesei having a course of 2500, the Lena of 2000 miles; so that we may easily conceive that the bodies of animals which fall into their waters may be transported to vast distances towards the arctic sea, and, before arriving there, may be stranded upon and often frozen into thick ice, and afterwards, when the ice breaks up, be floated still farther towards the ocean, until at length they become buried in fluviatile and submarine deposits near the mouths of rivers. Humboldt remarks that near the mouths of the Lena a considerable thickness of frozen soil may be found at all seasons at the depth of a few feet; so that if a carcass be once imbedded in mud in such a region and in such a climate, its putrefaction may be arrested for indefinite ages.” It would doubtless be impossible for herds of mammoths and rhinoceroses to obtain subsistence at present, even in the southern part of Siberia, covered as it is during a great part of the year with snow : but there is no difficulty in supposing a vegetation capable of nourishing these great quadrupeds to have once flourished between the latitudes 40° and 60° N., resembling perhaps that of England; for we have seen that there are proofs of the mammoth having co-existed with a large proportion of the living species of British testacea. It has been well observed by Dr. Fleming, that “the kind of food which the existing species of elephant prefers will not enable us to determine, or even to offer a probable conjecture, concerning that of the extinct species. No one acquainted with the gramineous character of the food of our fallow-deer, stag, or roe, would have assigned a lichen to the rein-deer.” Travellers mention that, even now, when the climate of eastern Asia is so much colder than the same parallels of latitude farther west, there are woods not only of fir, but of birch, poplar, and alder on the banks of the Lena as far north as latitude 60°. Formerly, when the arctic lands were less extensive, the temperature of the winter and summer may have been more nearly equalized, and the increasing severity of the winters, rather than a diminution of the mean annual temperature, may have been the chief cause of the extermination of the mammoth. It is probable that the refrigeration of the climate of north-eastern Asia was accompanied, and in a great measure caused, by changes in its physical geography. The whole country, from the mountains to the sea, may have been upraised by a movement similar to that which is now expe

* Humboldt, Fragmens Asiatiques, ton. ii. p. 393.

« FöregåendeFortsätt »