labors to establish his doctrine are the similitude of the most ancient traditions among all branches of the human species, the affiliation and analogy of languages, and the identity of organization and equality of aptitudes. He finds similar traditions among the Hebrews, the Chaldeans, the Phoenicians, the Egyptians, the Ethiopians, the Hindoos, the Persians, the Chinese, the Thibetans, the Scythians, and the Americans. In the theogonies and cosmogonies of the Aztecs of America, he says that the traditions of ancient Asia are plainly to be found, while some vague traces of these primitive narratives are to be found even among the savages of Oceanica, and the most barbarous and miserable negroes of western Africa. To the negroes he devotes perhaps the most careful and learned portion of the work. Starting from the discovery of M. Flaurens as to the _pigmentum_ or coloring matter of the skin, he contends with great force that nothing but the gradual influence of climate, giving a greater and greater intensity to the action of this coloring matter, which exists in every race and every individual, has caused the essential difference between whites and blacks. For, he argues, there is no other difference between them than that of color, all the other features, such as the prominent mouth, the woolly hair, the facial angle, being in no wise exclusively peculiar to the Africans. And so, after having gone over the entire race in detail, proving the identity of organization in every division, M. de Salles concludes that the primitive complexion was olive, somewhat like the color of unburnt coffee, and the original men had red hair. On the affiliation of languages he reasons at great length, with a striking affluence of curious and learned detail. Languages, he remarks, become more and more complicated and perfect as we ascend toward their origin. Next he considers the modifications by which the present races of men have departed from the first family, and in so doing he takes up every people that has ever been known. America, he thinks, was first settled by Mongol emigration, with religious traditions, between the eighteenth and the fifteenth century before our era: then, six or eight hundred years later, there was a second emigration of Hindoo races, with traditions of architecture. With the Bible and the facts of geology as his starting point, he demonstrates the falsity of the Egyptian, Hindoo, Chinese, and Mexican chronologies. The six days of creation he takes as so many great epochs; the deluge he places at five thousand years before Christ.