ignorant. It was then that, weak and almost naked, having only just got fire and a few rude arms with which to defend itself and procure food, the human race conquered the world and spread itself from within the Arctic Circle to Terra del Fuego, from the Samoyed country to Van Diemen's Land, from the North Cape to the Cape of Good Hope. It is this primitive exodus, as certain as it is inconceivable, accepted by science as well as by dogma, that we have to explain, or at least to make probable; and that in an age when it is only after the most wonderful discoveries, by the aid of the most powerful machinery for navigation, through the boldest and most adventurous enterprises, that civilized man has been able to flatter himself that he has at last gone as far as infant man went in an age that is so far removed from us as to baffle all calculations.
We must insist on this point, for it brings into light an obstacle which those who have tried to trace out the connection between widely separated races and to determine the course that had been followed by tribes now separated by oceans and vast expanses have hitherto found insurmountable; for, if man is one—to which we are ready to agree—we must assign a single point of departure for his migrations. In these migrations, man has gone wherever he could, and, at every spot he has occupied and settled, has acquired characteristics peculiar to the place, and which differentiated him from the men settling in other places. Hence the varieties in human races. Some of these spots seem to have been peculiarly favorable to his advancement, and became centers of civilization. The number of such centers is, however, very limited, and their distribution is significant.
The continental masses are distributed in three principal groups, one feature in the configuration of which must strike every one who carefully examines a map of the world. It will be noticed that they are so expanded toward the north as to touch in that direction or be separated only by narrow passages, and that they also surround within the Arctic Circle a central polar sea with a bordering island-belt. Going down toward the south we find that the three continents, North America, Europe, and Northern Asia, which had approached each other so closely, give place to three appendages, South America, Africa, and Australia, which in their turn gradually taper off to mere points in an illimitable sea, long before they reach the Antarctic Circle. Within this circle the configuration of the land is precisely the reverse of that in the north; it is that of a solid cap of land around the pole, in the midst of the great ocean.
If we again observe these masses, we shall find that civilization was born in each of them under similar geographical conditions, viz., in the neighborhood of a smaller interior sea, near or rather north of the tropic of Cancer, between 20° and 35° north latitude. The most eastern of the centers is in China, near the Japan Sea. The most western, and apparently the most recent, was along the inner shores