In the same way it has been established that, on our own continent, the oldest discoverable civilization was one in which rude stone implements were used, and man lived contemporaneously with the megatherium and the mastodon. Then polished and worked stone implements came into use; and after the lapse of ages, copper. The researches of our antiquaries have rendered it probable that America is as ancient, as an inhabited continent, as Europe. Evidences have been brought to light, leading to the conclusion that many thousands of years before the Christian era, America was the seat of a civilization far from rude or savage. Groping into the remains of the far past, we find skeletons, skulls, implements of war, and even basket-work, buried in geological strata, which have been overlaid by repeated convulsions and changes of the physical earth. But so few are the relics of this dim, primeval period, that we can only conclude its antiquity, and we can infer little or nothing of its characteristics. [Sidenote: Primeval Races.] Advancing, however, another stage in research and discovery, we come upon clear and overwhelming proofs of the existence on this continent of a great, enterprising, skilful, and even artistic people, spread over an immense area, and leaving behind them the most positive testimony, not only of their existence, but of their manners and customs, their arts, their trade, their methods of warfare, and their religion and worship. Compared with this people, the Red Indians found here by the Pilgrims and the Cavaliers were modern intruders upon the land. These ancient Americans, indeed, were far superior in all respects to the Red Indian of our historic acquaintance. When the Red Indians replaced them, the civilization of the continent fell from a high to a much lower plane. [Sidenote: The Mound-Builders.] The great race of which I speak is known as "the Mound-Builders." Like the "Wall-Builders" of Greece and Italy, they stand out, in the light of their remains, as distinctly as if we had historical records of them. The Mound-Builders occupied, often in thickly settled communities, the region about our great Northern Lakes, the valleys of the Mississippi, the Ohio, the Missouri, and the regions watered by the affluents of these rivers, and a wide and irregular belt along the coast of the Gulf of Mexico. There is little or no evidence that the same race inhabited any part of the country now occupied by the Eastern and Middle States; but some few traces of them are found in North and South Carolina. [Sidenote: Ancient Mounds.]