18 ABORIGINAL MONUMENTS
of these, while they are found indiscriminately upon all the others, bears directly upon the question of their antiquity.
These general remarks will serve to introduce one or two examples of Defensive Works, which will best illus- trate their general character.
Plate 2.—This fine work is situated in Butler county, ‘Ohio, three miles below the town of Hamilton, on the west side of the Great Miami river. The hill, the summit of which it occupies, is about half a mile distant from the present bed of the river, and is not far from two hundred and fifty feet high, being considerably more elevated than any other in the vicinity. Itis surrounded at all points, except a narrow space towards the north, by deep ravines, present- ing steep and almost inaccessible declivities. The slope towards the north is very gradual, and from that direction the hill is easy of approach. It is covered by a primitive forest.
Skirting the brow of the hill, and generally conforming to its outline, is a wall of mingled earth and stone, haying an average height of five feet by thirty-five base. It has no apparent ditch, the earth composing it, which is a stiff clay, having been for the most part taken up from the sur- face, without leaving any marked excavations. There area number of pits or “dug holes,” however, at various points within the walls, from which it is evident a portion of the material was obtained. The wall is interrupted by four openings or gateways, each about twenty feet wide; one fronting the north, on the approach above mentioned, and the others occurring where the spurs of the hill are cut off by the parapet, and where the declivity is least abrupt. They are all, with one exception, protected by inner lines of embankment of a most singular and intricate description. These are accurately delineated in the plan, which will best explain their character. It will be observed that the north-. ern or great gateway, in addition to its inner maze of walls,
