Page:Observationsonab00squi.djvu/17

14 we go down the Mississippi towards the Gulf. And although between the monuments of the North and the South there is a marked contrast, in many respects; yet it would be impossible to tell, so gradually do they merge into each other, where one series terminates and the other begins. It is not impossible that future investigations may show an imperceptible transition from the more regular earth-structures of the lower Mississippi, to the symmetrical and imposing stone teocalli of Mexico.

The remains of which we are speaking may be divided into two grand classes, viz.,, bounded by parapets, circumvallations or walls, and simple Tumuli or They constitute together a single system of works; but, for purposes which will satisfactorily appear, it is preferred to classify them as above. These grand classes resolve themselves into other minor divisions: Enclosures are for defence, for sacred or superstitious and for other purposes not easily explained; and the Mounds are places of sepulture, of sacrifice, &c.

The Enclosures, or, as they are familiarly known throughout the West, "Forts," constitute a very important and interesting class of remains. Their dimensions, and the popular opinion as to their purposes, attract to them more particularly the attention of observers. As a consequence, most that has been written upon our antiquities relates to them. Quite a number have been surveyed and described by different individuals, at different times; but no systematic examination of a sufficient number to justify any general conclusion as to their origin and purposes has hitherto been made. Accordingly we have had presented as many different conclusions as