But I have already exceeded the limits prescribed for this book. In concluding, I would say that it seems from all the evidence available that this continent was peopled at a period so remote that other races had not yet developed their present characteristics. This was probably before the glacial epoch began, while the Northern climate was mild, and while land surfaces were distributed more on latitudinal lines, separated by narrower waters. Afterwards there was a rearrangement by the forces of nature, which, together with the extreme cold of the North, effectually separated the Amerinds from other peoples, and caused them to mingle and react on each other till even the affinities which had before developed in different localities and had produced some differentiation of types were almost rubbed out and remain to-day only as tinges of the earlier qualities. The other world tribes, subjected to other influences, have developed other differences and have diverged from their original stocks. It is also probable that in the redistribution of land surfaces and rearrangement of land levels, many stocks, some highly developed, were obliterated. Slight modifications may have occurred through later accidental intrusions from the Eastern Hemisphere, but if there had been any considerable intercourse within a recent period between outside peoples and the Amerinds we should have found distinct traces of it in the writings of early days. People as different and extraordinary as the Amerinds were would have produced a vivid impression on any who might have seen them and contrariwise a European, for example, would have left a lasting impression. On the extreme North-west coast there seems to be a type resemblance to Asiatics, but this is more likely due to an extremely early colouring which was preserved by special isolation on this continent, rather than to any considerable infusion of Asiatic blood in recent time. As before remarked, I am of the opinion that the Alaska and North-west coast tribes reached those regions from the South and South-east in comparatively late times.[406] Taking a broad view of the question, it seems to be an inevitable conclusion that the Amerind race, or rather _the various races of which it was originally composed_, were early cut off on this hemisphere from intercourse with the remainder of the world, and held in isolation by a change in land distribution and by the continued glaciation of the northern portions of the continent which in a measure endures to this day. The climate of North-eastern Siberia was also glacial and prevented migrations from milder regions. Many eminent archæologists agree that the Amerind was here before the great cold moved down, although the evidence of implements and remains as we now understand them is, perhaps, insufficient. Languages, traits, customs, and arts are also to be considered, and they seem all to favour, as outlined above,