Note 193 — Chapter IV · MEXICAN HIEROGLYPHICS—MANUSCRIPTS—ARITHMETIC—CHRONOLOGY—ASTRONOMY

Thus, their astrological year was divided into months of thirteen days; there were thirteen years in their indictions, which contained each three hundred and sixty-five periods of thirteen days, etc. It is a curious fact that the number of lunar months of thirteen days contained in a cycle of fifty-two years, with the intercalation, should correspond precisely with the number of years in the great Sothic period of the Egyptians, namely, 1491; a period in which the seasons and festivals came round to the same place in the year again. The coincidence may be accidental. But a people employing periodical series and astrological calculations have generally some meaning in the numbers they select and the combinations to which they lead.