We may, I think, at once take it for granted, that none of the Neocosmic races date farther back than the origin of the great eastern nations. There are certainly no geological evidences requiring a greater antiquity, for in their time the land had attained to its present configuration, and the changes which have occurred in the succession of forests and the growth of peat are such as our experience in America shows to be possibly quite modern. There is besides no doubt that these people, from the Reindeer men of France and Belgium to the people of the Swiss lakes, are modern races, whose descendants still live in Europe. We can thus limit our inquiry to the Palæocosmic men; and with respect to them we know only what may be gathered from a consideration of the physical changes which have occurred since they lived. In Europe a great number of considerations have been adduced as evidence of their high antiquity; and these deserve careful attention, though I think it will be found that they are all liable to serious objections or great abatements on geological grounds. (1) The occurrence of human remains with those of animals now extinct affords no certain evidence of antiquity. Admitting that human remains are found along with those of the mammoth in Europe, and with those of the mastodon in America, the question remains, How late did these species survive? In Europe we know that several large animals now extinct existed up to comparatively modern times. This is the case with the Irish deer (_Megaceros_), the urus, the aurochs, and the reindeer, in temperate Europe. How long previously the mammoth or the hairy rhinoceros disappeared we do not know, but need not suppose the time very long. (2) The accumulation of sediment or of stalagmite over human remains in caverns is not necessarily indicative of very great antiquity. We know that in favourable circumstances mud, sand, and gravel may be rapidly deposited in caves by land floods or river inundations, and that _débris_ of various sorts accumulates in such places from decay of rock and vegetable and animal agencies. The deposition of stalagmite is also very variable in its rate; and the fact that it is being very slowly deposited in any cave now does not prove that more rapid deposition may not have taken place formerly. Dawkins and others have ascertained a rate of a quarter of an inch per annum in some caverns; and this would allow the stalagmite crust of Kent’s cave, for which an antiquity of half a million of years has been claimed, to have been formed in a thousand years. [Illustration: FIG. 192.—Sketch of a Mammoth, carved on a portion of a Tusk of the same Animal (Lartet).]