Maps and manuscripts were painted on fine cloth made of aloe- or palm-fibre, paper made from the aloe, or dressed skins, the two former being coated with a kind of size. The colours were applied with a brush, which was moistened with the lips of the artist, and the designs were invariably outlined in black. A considerable variety of colours was employed, red from cochineal or log-wood; two yellows, vegetable and mineral; blue from certain flowers; white from chalk, and black from the soot of the ocotl palm. The mixing of colours was understood, and brilliant greens, purples and browns are found. It will be readily understood that the service of so many gods and so formidable a list of religious festivals required the services of a large body of carefully trained priests. The office of priest was one which had undergone considerable evolution in Mexico, at least as far as the immigrant tribes were concerned. At first the priest was also the temporal leader; his principal duty was the care of the image of the tribal god, which he carried during the wanderings of the tribe; and since it was the god who directed those wanderings, and the priest was the sole interpreter of his wishes, it came about that the priest was also the director of the tribal policy. But once the tribe became settled, there was a tendency for the priest to become less and less a man of action, and to concentrate his energies on the elaboration of ritual and the study of astronomy. At the same time there was no sharp division between the temporal and religious authority; the king exercised many priestly functions, and the priesthood possessed enormous influence in national affairs. Priests even engaged in war, and there was a special series of _insignia_ worn in fight by those who had distinguished themselves in battle by the capture of one or more prisoners. In Mexico itself at the head of the hierarchy were two chief priests, each of whom bore the title of Quetzalcoatl (since the god of that name was regarded as the prototype of all religious orders), and who were distinguished by the names of Totec Tlamacazqui and Tlaloc Tlamacazqui. The first was the priest of Uitzilopochtli, the second of Tlaloc; they were equal in status, and both were selected from the upper grade of religious officers in virtue of their wisdom, piety and general good character, irrespective of their birth. Subordinate to them was a minister called Mexicatl Teohuatzin, whom Sahagun terms a “patriarch,” and who acted as general overseer of ritual and of the priestly college called Calmecac. He was assisted by two other functionaries, the Uitznauac Teohuatzin and the Tepan Teohuatzin, the latter of whom shared his responsibilities as an educational officer. Beneath these dignitaries were ranked an upper grade of priests, called Tlanamacac, and a lower grade, Tlamacazqui; and finally the novices, Tlamacazton. The priests of the upper grade included a number of functionaries with special titles, who were