They have attributed it to the knowledge of the solstices and equinoxes, but assuredly it is of more ancient date than this.

The same explanation has been offered for its recurrence among the Nahuas of Mexico, whose whole lives were subjected to its operation.

At birth the mother was held unclean for four days, a fire was kindled and kept burning for a like length of time, at the baptism of the child an arrow was shot to each of the cardinal points.

Their prayers were offered four times a day, the greatest festivals were every fourth year, and their offerings of blood were to the four points of the compass.

At death food was placed on the grave, as among the Eskimos, Creeks, and Algonkins, for four days (for all these nations supposed that the journey to the land of souls was accomplished in that time), and mourning for the dead was for four months or four years.[73-1] It were fatiguing and unnecessary to extend the catalogue much further.
Yet it is not nearly exhausted.