Man could not stay there forever. He was bound to spread to new regions, partly because of his innate migratory tendency and partly because of Nature's stern urgency.

Although farming of any sort was almost as impossible in the plains as in the dry regions of winter rains farther west, the abundance of buffaloes made life much easier in many respects.

Year by year we are learning that in this restless, strenuous American life of ours vacations are essential.

From first to last the civilization of America has been bound up with its physical environment.

Although mountains may guide migrations, the plains are the regions where people dwell in greatest numbers.

Thus the races, though alike in their physical response to climate, may possibly be different in their mental response because they have approached America by different paths.

The coast of British Columbia was one of the three chief centers of aboriginal America.