It is clear that when we speak about the migration of the Americans at a time when the polar half of each continent was either covered with a glacier thousands of feet thick, or submerged to that depth beneath an arctic sea, we have to do with geographical conditions totally unlike those of to-day. I call attention to this obvious fact because it has not been obvious to all writers.

In your archæological reading you will rarely 오피알바come across a prettier piece of theoretical history than Mr. Lewis A. Morgan’s description of the gradual peopling of the two Americas by tracing the lines of easiest subsistence. He begins at the fishy rivers of the northwest coast, and follows the original colony which he assumes landed at that point, 45all the way to Patagonia and Florida.[31] But how baseless becomes this vision when we consider the geography of America as it is shown by geology to have been at a period contemporary with the earliest remains of man! We know to a certainty that the human race had already spread far and wide over both its continental areas before Mr. Morgan’s lines of easiest nutrition had come into existence.

Properly employed, a study of those geologic features of a country which determine its geography will prove of vast advantage in ascertaining the events of pre-historic time. These features undoubtedly fixed the lines of migration and of early commerce. Man in his wanderings has always been guided by the course of rivers, the trend of mountain chains, the direction of ocean currents, the position of deserts, passes and swamps. The railroad of to-day follows the trail of the primitive man, and the rivers have ever been the natural highways of nations. The theories of Morgan therefore remain true as theories; only in their application he fell into an error which was natural enough to the science of twenty years ago. Perhaps when twenty years more shall have elapsed, the post-tertiary geology of our continent will have been so clearly defined that the geography of its different epochs will be known sufficiently to trace these lines of migration at the various epochs of man’s residence in the western world, from his first arrival.