One additional group of ruins, as yet unclassified with any of the types we have described, merits our attention. This group is known as Los Edificios of Quemada, situated in southern Zacatecas north of the Central plateau and probably the home of the Chichimecs.[547] Mr. Bancroft has attempted to reconstruct the unsatisfactory accounts of the several explorers of Quemada, but with little success. We therefore decline adding another comparative failure to the list of literature on these ruins. Some general observations, however, may not be out of place. The Cerro de los Edificios is a natural eminence about half a mile long and between one hundred and two hundred yards wide, except at its southern extremity where it increases to a width of five hundred yards. The authorities differ as to its height, one saying from two to three hundred feet, and another eight to nine hundred feet above the plain. Ancient roads well paved radiate in various directions from the hill, some of them extending a distance of five or six miles. The northern brow of the hill, where the descent is not so precipitous as at the other points, is guarded by a stone wall, as are all other points where the precipitous sides do not offer a sufficient barrier to an intruder from without. The surface of the hill is quite uneven, and these irregularities have been formed into terraces supported by stone walls. Foundations have thus been secured for a multitude of structures, some of them perfectly pyramidal and others consisting of quadrangular enclosures or squares, terraced and having steps descending to the court within, where pyramidal structures of stone are found. On the eastern terrace of the Cerro, a round pillar, eighteen feet high and nineteen feet in circumference, stands in proximity to a wall of as great height as the pillar. Traces of nine similar pillars are visible, and the probability is that they formed part of a balcony or perhaps a portico. Adjoining this wall is an enclosure measuring 138 by 100 feet, in which are eleven pillars in line, each seventeen feet in circumference and as high as an adjacent wall, namely eighteen feet. The distance from the wall is twenty-three feet, and the presumption is that the pillars supported a roof. There are no doorways, properly so called, since the doorways are large quadrangular openings extending to the full height of the halls. No windows were discovered anywhere. The material is gray porphyry from hills across an intervening valley, and the mortar is reddish clay, mixed with straw, and is of poor quality. Sculpture, hieroglyphics, pottery, human remains, idols, arrow-heads, and obsidian fragments are totally wanting, thus presenting a strange contrast with all other Mexican ruins. Nevertheless, the massiveness of the fortifications, the height and great thickness of the walls, none of which are less than eight feet thick and in one instance over twenty, the extensive system of paved roads, besides great elevated