From the elliptical enclosure a wide avenue of two dissimilar parts, seemingly constructed without relation to each other, leads to a square of twenty acres, with seven mounds disposed symmetrically within the enclosing walls, and numerous other works occupy hundreds of acres with their geometrical configurations. But in spite of the intelligent interest which prevails in reference to those remarkable monuments of an ancient people, the industrial operations of the modern occupants of their sites are fast obliterating all but the most prominent works. In the great octagon I noticed a difference of nearly five feet between the height of the embankments still standing on uncleared land, and those portions which have been long under the plough. But for the aid of my intelligent guide I should have found it impossible to trace out the indications of the parallel ways; and already many of the smaller mounds and enclosures have entirely disappeared. Roads, railways, and a canal, have successively invaded the sacred enclosures, and wrought more changes in a single generation than had been effected in all the previous interval since the discovery of America. But the accompanying plan (Fig. 70), derived from surveys executed while the chief earthworks could still be traced in all their integrity, will enable the reader to comprehend their character; and if he clearly realises the scale on which these geometrical figures are constructed, he can be at no loss in recognising their essential difference from the ephemeral earthworks which mark the sites of Indian stockades or sepulchral mounds. While they present certain analogies to mound-groups and enclosures both of Europe and Asia, in many other respects they are totally dissimilar: and illustrate rites and customs of an ancient American people without a parallel among the monumental memorials of the Old World. [Illustration: FIG. 70.—Newark Earthworks, Ohio.]