parapet, built of stones without mortar, rises five and a half feet above the plaza, and is two feet and nine inches thick, we presume at its top, since the outer slope of the terrace would make a difference between the top and bottom. Near the centre of the plaza stands the base of a pyramid which presents some remarkable architectural contrasts from anything we have thus far described. Its sides face the cardinal points, and measure sixty-five feet from east to west, and fifty-eight feet from north to south. One of the façades, the northern, according to Nebel, and the western, according to the Mexican Government Survey in the _Revista_, is cut in two in the centre by an opening twenty feet wide, where it is supposed a stairway formerly led to the superstructure. The cut from Nebel, and reproduced by Mr. Bancroft, shows the façade to the left of the opening, as the observer faces the pyramid. [Illustration: Pyramid at Xochicalco.] The great granite or porphyritic stones which constitute the facing of the pyramid, some of them eleven feet in length and three feet in height, must have been brought to the summit of the hill at the expense of great labor, especially since they must have been transported from a considerable distance, no such material being found within a circuit of many leagues. The stones were laid without mortar, and so nicely that it is said the joints are scarcely perceptible. Fragments of a ruined superstructure surmount the pyramid. The foundation walls of the second story were two feet and three inches from the edge of the cornice below it, except on the west where the space was four and a half feet wide. In 1755, so say the inhabitants of the vicinity, the structure was yet complete, having five receding stories like the first, and probably reaching a height of sixty-five feet. On its crowning summit, on the eastern side, stood a large throne-like block of stone, ornamented with elaborate sculptures. The second story foundations indicate the position of three doorways at the head of the grand stairway, and the account in the _Revista_ describes an apartment twenty-two feet square observable at the summit of the first story, but now filled with fragments of stone. Mr. Bancroft suggests that from this apartment there may have been some means of communication with the subterranean galleries already described. The colossal sculpture on the face of the pyramid will receive our attention on a future page.[540]