The dark upright and light inverted peaks were evidently employed as familiar and favorite emblems of earth and heaven. [Illustration.] Figure 45. I am inclined to see in the serrated summit of the remarkable edifice, known as the House of Doves at Uxmal, a rendering of the same symbolism on a gigantic scale (fig. 45). It cannot but be recognized, moreover, that a high edifice presenting a regular series of cones, and extending from east to west, would have afforded an excellent means of registering the varying positions of heavenly bodies. To observers looking towards it from the north or south, at judiciously chosen distances, the entire span of the sky would have seemed divided into eight equal parts, seen as inverted air pyramids between nine sections which rise in steps and terminate in points, each gable being perforated with thirty window-like openings, arranged in seven horizontal rows. The purpose of these gable-like piles has been a riddle to the archaeologists, who have visited Uxmal. Dr. Wm. H. Holmes, from whose valuable works I cite the above descriptions, expresses his wonder at “the great building, bearing upon its roof a colossal masonry comb, built at an enormous expenditure of time and labor ... which seemed to have been built exclusively for the purpose of embellishing the building and holding aloft its sculptured ornaments” (Ancient cities of Mexico, pl. I, p. 95). I venture to maintain that this remarkable edifice not only afforded facilities for astronomical observation but constituted in itself a great prayer for rain wrought in stone and addressed to the Lord of Heaven by a devout people. In corroboration of this inference, besides the foregoing data, I point out that to this day the Pueblo Indians associate the step pyramid form with beneficent rain and even give this shape to the edges of the sacred bowls which are carried in the ceremonial dances by the “rain-makers.” According to Mr. Cushing the Zuñis compare the rim of such bowls to the line of the “horizon, terraced with mountains, whence rise the clouds.” He was likewise informed that the terrace form represents “the ancient sacred place of the spaces,” an expression which, though somewhat vague, seems to corroborate my view of the Uxmal building. The Zuñi statement that the terrace form figured mountains leads to the subject of so-called “mountain worship.” In ancient Mexico, at the approach of the rainy season, religious ceremonies are performed in honor of the mountains which were looked upon as active agents in the production of rain, because they attracted and gathered the clouds around their summits. The tops of mountains were thus regarded as the sacred place where the sky and heaven met and produced the showers which vivified the earth. Pilgrimages and offerings to mountain summits formed a part of the duties of the Mexican priesthood, but in the cities the pyramid temple