at least a thousand years had elapsed since the country was abandoned by its former inhabitants, and their fields and villages were overgrown by the forest. Beyond this point all dates are left to conjecture.
One interesting feature in the Western mounds is that many of them, especially in the prairie regions of the Northwest, are made to imitate, on a gigantic scale, the forms of men, quadrupeds, and birds, and among the animals thus represented is what seems to be the elephant or mastodon. Small figures of an elephantine animal also appear in the archæological collections of the Northwest, and are claimed to be authentic. These relics go far to prove the acquaintance of the mound-builders with either the mastodon or mammoth, and may be accepted as presumptive evidence of the synchronism of man here, as in Europe, with one or both of these great pachyderms—and hence of his great antiquity.
The Palace-builders.—The remains of an ancient civilization, scattered over the west coast of South America, the Isthmus, and Mexico, are so varied and interesting that they form a theme to which nothing like justice can be done in the few minutes at my disposal. Detailed descriptions of these great monuments are, however, the less necessary, since many volumes have been devoted to their exposition. Those who have access to Squier's Peru, Stephens's and Catherwood's, Norman's and Waldeck's books on Central America, or Lord Kingsborough's great work on Mexican Antiquities, will find there, and in the documents cited by their authors, a literature scarcely less rich and interesting than that formed by the records of the Egyptians or Assyrians.
Of this vast field I can give you but the merest sketch, but, as part of it lies within our own territory, and as in its exploration I have taken part, I can perhaps add some facts additional to those you have learned, and such as will compensate for the time they may occupy. To summarize, as briefly as possible, the knowledge we have of this subject, I may say that from the frontier of Chili to Salt Lake, there exists an almost uninterrupted series of monuments of a civilization which, though locally peculiar, was generically the same, and unquestionably the product of divergent streams flowing from a single source. The typical and characteristic remains of this civilization consist of great works of masonry and engineering (fortifications, temples, palaces, communal houses), which in their magnitude and perfection of workmanship rival the masterpieces of ancient architecture. Bridges, aqueducts, and thousands of miles of paved and graded roads attest the engineering skill of the people by whom they were constructed.
Honduras, Yucatan, and Colombia would seem to have been the
