The Aztecs believed that eternity was broken up into several distinct cycles, each of several thousand years' duration. There would seem to have been four of these periods, concerning the length and nature of which the old Spanish writers on the subject differ very materially. The conclusion of each was (according to the Mexican tradition) to witness the extinction of humanity in one mighty holocaust, and the blotting out of the sun in the heavens. Whether this universal upheaval applied only to the sons of men, or, like the Teutonic Gotterdämmerung, or the Scandinavian Rägnarok, had an equal significance for the gods, is not clear. It is worth remarking, however, that it premises the mortal nature of the sun, and, therefore, the existence of a creative agency with the ability to set another sun in its place. With the Mexicans the question of a future life was a very nebulous one, though perhaps no more so than with the ancient Greeks or Romans. There was more than one paradise. Mictlan, the shadowy sombre place of the dead, was the resting-place of the majority, for the Aztecs fully believed that the higher realms of bliss were preserves for the aristocracy where the lowly might not enter. And this, in passing, is perhaps an explanation of the marvellously speedy adoption of Christianity by the Mexican natives subsequent to the conquest of Anahuac. Of the higher realms of bliss the 'Mansion of the Sun' was perhaps the most desirable. There the principal pleasures consisted in accompanying the sun in his course, and the amusement of choral dancing. Souls in this paradise might also enter the bodies of humming-birds, and flit from flower to flower. The exercise of the chase lent to this place something of the character of a Valhalla, and we hear something of Gargantuan banquets. Here, too, the blessed might animate the clouds, and float deliciously over the world they had quitted. The paradise of Tlaloc was the special dwelling of those who had lost their lives by drowning, of sacrificed children, and of those who had died of disease caused by damp or moisture. But two exceptions were made as regarded the souls of others, and these related to warriors slain in battle, and women who had died in child-bed, who were permitted to enter paradise as having forfeited their lives in the service of the state.