look or defence, and others for sepulture. The unknown people by whom they were constructed, judging by the form of several skulls dug out of the burial-places, were of the Mexican or Toltecan race. Some of the earthworks are on so grand a scale as to embrace areas of fifty or a hundred acres within a simple enclosure, and the solid contents of one mound are estimated at twenty millions of cubic feet, so that four of them would be more than equal in bulk to the Great Pyramid of Egypt, which comprises seventy-five millions. From several of these repositories pottery and ornamental sculpture have been taken, and various articles in silver and copper, also stone weapons, some composed of hornstone unpolished, and much resembling in shape some ancient flint implements found near Amiens and other places in Europe, to be alluded to in the sequel.
It is clear that the Ohio mound-builders had commercial intercourse with the natives of distant regions, for among the buried articles some are made of native copper from Lake Superior, and there are also found mica from the Alleghanies, sea-shells from the Gulf of Mexico, and obsidian from the Mexican mountains.
The extraordinary number of the mounds implies a long period, during which a settled agricultural population had made considerable progress in civilization, so as to require large temples for their religious rites, and extensive fortifications to protect them from their enemies. The mounds were almost all confined to fertile valleys or alluvial plains, and some at least are so ancient, that rivers have had time since their construction to encroach on the lower terraces which support them, and again to recede for the distance of nearly a mile, after having undermined and destroyed a part of the works. When the first European settlers entered the valley of the Ohio, they found the whole region covered with an uninterrupted forest, and tenanted by the Red Indian hunter, who
