2nd. There is not always so peculiar a class of physical conditions as is to be found in the mountain fastnesses of Caucasus to account for it; since in America we find steppes and prairies, like those of Turkestan and Mongolia, inhabited by tribes as different from each other as those of the most isolated and isolating mountain-valleys.
Furthermore—when the American languages differ from one another, they differ in a manner to which Asia has supplied no parallel.
Also—when the American languages agree with one another, they agree in a manner to which Asia has furnished no parallel. This, however, is at present only indicated. Its explanation will find place when we have treated of the Eskimo, Kolúch, and certain other families.
THE ESKIMO.
Unimportant as are the Eskimo in a political and historical view, their peculiar geographical position gives them an importance in all questions of ethnology: since one of the highest problems turns upon the affinities of this family.
It has long been known that the nation which inhabits Greenland and Labrador is the nation which inhabits the North-western parts of Russian America as well. It is found on the American side of Behring's Straits, and it is found on the Asiatic side also. So that the Eskimo is the only family common to the Old and New World; an important fact in itself, and one made more important still by the Eskimo localities being the only localities where the two continents come into proximity.
Now, if these facts had stood alone, unmodified by any phænomena that detracted from their significance, the peopling of America would have been no more a mystery than the peopling of Europe. Such, however, is not the case. They neither stand alone, nor stand unmodified.
The reasons that lie against what is, at the first blush, the common sense answer to the question, how was America peopled? are, chiefly, as follows—
1. The distance of the north-eastern parts of Asia from any probable centre of population—cradle of the human race—so-called. For these parts to have been the passage, Kamskatka must have been full to overflowing before the the Mississippi had been trodden by the foot of a human being.
2. The physical differences between the Eskimo and the American Indian.