Perhaps the strongest proof of the advanced civilization of the Nahuas was their method of computing time, which, for ingenuity and correctness, equaled, if it did not surpass, the systems adopted by contemporaneous European and Asiatic nations.
The Nahuas were well acquainted with the movements of the sun and moon, and even of some of the planets, while celestial phenomena, such as eclipses, although attributed to unnatural causes, were nevertheless carefully observed and recorded. They had, moreover, an accurate system of dividing the day into fixed periods, corresponding somewhat to our hours; indeed, as the learned Sr Leon y Gama has shown, the Aztec calendar-stone which was found in the plaza of the city of Mexico, was used not only as a durable register, but also as a sun-dial.
THE AZTEC CALENDAR.
Although the system of the Aztec calendar as a whole is clear and easily understood, yet it is extremely difficult to describe with certainty many of its details, owing to the contradictory statements of nearly all the earlier writers, who visited Mexico and there in different localities picked up scraps of what they afterwards described as being the 'calendar of the Mexicans,' not taking into consideration that the many and distinct kingdoms surrounding the Aztec territory, although using essentially the same system, differed on many important points, such as the names of years, months, days, the season of beginning the year, etc. This difficulty increases when we attempt to make Mexican dates agree with our own. Even Boturini, who gathered his information in Mexico, makes many mistakes; and Veytia, although we must accord him the credit of having thoroughly studied the subject, and of having reduced it to a clear system, is at fault in many points. Of the older writers, such as Sahagun, Las Casas, Duran, Motolinia, and others, no one is explicit enough on all points to enable us to follow him; and such details as they unite in giving are mostly contradictory. Torquemada, who draws a great portion of his material from Motolinia, contradicts himself too frequently to be reliable. Leon y Gama, although he spent much labor in trying to clearly expound the system, has also fallen into some errors, attributable, perhaps, to his not having the valuable aid of Sahagun's writings, and to his having placed too much trust in the writings of Torquemada and the manuscript of the Indian Cristóbal del Castillo, as is shown in the review of Gama's work by Sr José Antonio Alzate in the Gacetas de Literatura. Baron von Humboldt's description, valuable as it is on account of the extended comparisons which he draws between the Mexican, Asiatic and Egyptian calendars, is on that account too intricate to be easily understood. From all these descriptions Gallatin, McCulloh, and Müller, with perhaps a few others, have each given us a very good résumé, but without attempting to reconcile all the contradictions.
The first notice we have of any regular calendar is given by Ixtlilxochitl, who states that in the year 5097 from the creation of the world, an assembly of learned men met at the city of Huehuetlapallan, and determined the reckoning of the years, days, and months, leap years and intercalary days, in the order in which they were found at the time of the conquest.[618] Previous to this time it is said that the only reckoning kept was regulated by the yearly growth of the fresh grass and herbs from which the name of the Mexican year xihuitl, 'new grass,' is derived. It is also said that a rough computation of time was made by the moon, from its appearance to its disappearance, and that this period called metztli, 'the moon,' was divided into two equal parts, named respectively mextozolitzli, the time when the moon was awake or visible, and mecochiliztli, the sleep of the moon, or the time when it was invisible.[619] Of the larger divisions of time, accounts are very conflicting. Two, three, four, and five ages are said by various writers to have existed, at the end of each of which the world was said to have been destroyed, and recreated at the beginning of the age next following. The common aboriginal belief was, however, that at the time of the conquest, the world had passed through three ages, and was then in the fourth. The first age, or 'sun,' as it is also called, was the Sun of Water, atonatiuh; the second, the Sun of Earth, tlalchitonatiuh; the third, the Sun of Air, ehecatonatiuh.[620] This is about all we know of any division of time, before the assembly at Huehuetlapallan which is said to have introduced the regular calendar.
The Aztec Cycle.
THE MEXICAN CYCLE.
The Mexican calendar contains the following divisions of time: The 'age,' consisting of two periods of fifty-two years each, was called huehuetiliztli; the 'cycle,' consisting of four periods of thirteen years each, was named xiuhmolpilli, xiuhmolpia or xiuhtlalpilli, meaning the 'binding up of the years.' Each period of thirteen years or, as it was called by the Spanish historians, 'indiccion,' was known as a tlalpilli, or 'knot,' and, as stated above, each single year was named xihuitl, or 'new grass,' The age was not used in the regular reckoning, and is only rarely mentioned to designate a long space of time. The numeral prefixed to the name of any year in the cycle, or xiuhmolpilli, never exceeded four, and to carry out this plan, four signs, respectively named tochtli, 'rabbit,' calli, 'house,' tecpatl, 'flint,' and acatl, 'cane,' were used. Thus the Aztecs commenced to count the first year of their first cycle with the name or hieroglyphic Ce Tochtli, meaning 'one (with the sign of) rabbit;' and the second year was Ome Acatl, 'two, cane;' the third, Yey Tecpatl, 'three, flint;' the fourth, Nahui Calli, 'four, house;' the fifth, Macuilli Tochtli, 'five, rabbit;' the sixth, Chicoace Acatl, 'six, cane;' the seventh, Chicome Tecpatl, 'seven, flint;' the eighth, Chico ey Calli, 'eight, house;' the ninth, Chico nahui Tochtli, 'nine, rabbit;' the tenth, Matlactli Acatl, 'ten, cane;' the eleventh, Matlactli occe Tecpatl, 'eleven, flint;' the twelfth, Matlactli omome Calli, 'twelve, house;' and the thirteenth, Matlactli omey Tochtli, 'thirteen, rabbit.' This numeration continued in the same manner, the second tlalpilli commencing again with 'one, cane,' the third tlalpilli with 'one, flint,' the fourth with 'one, house,' and so on to the end of the cycle of fifty-two years. It will easily be seen that during the fifty-two years none of these four signs could be accompanied by the same number twice, and therefore no confusion could arise. Instead, therefore, of saying an event happened in the year 1850, as we do in our reckoning, they spoke of it as happening, for instance, in the year of 'three, rabbit' in the twelfth cycle.[621] Still, some confusion has been caused among different writers by the fact that the different nations of Anáhuac did not all commence their cycles with the same hieroglyphic sign. Thus the Toltecs commenced with the sign tecpatl, 'flint;' and the Mexicans, or Aztecs, with tochtli, 'rabbit;' while some again used acatl, 'cane;' and others calli, 'house,' as their first name.[622] A cycle was represented in their paintings by the figures of tochtli, acatl, tecpatl, and calli, repeated each thirteen times and placed in a circle, round which was painted a snake holding its tail in its mouth, and making at each of the four cardinal points a kink with its own body, as shown in the plate on the opposite page, which served to divide the cycle into four tlalpillis.[623] These four signs, rabbit, cane, flint, and house were also, according to Boturini, used to designate the four seasons of the year, the four cardinal points, and lastly, the four elements. Thus, for instance, tecpatl also signified south; calli, east; tochtli, north; and acatl, west. In the same manner tecpatl was used to designate fire; calli, earth; tochtli, air; and acatl, water.[624]
The civil year was again divided into eighteen months and five days. Each month had its particular name, but the five extra days were only designated as nemontemi or 'unlucky days,' and children born at this time, or enterprises undertaken, were considered unlucky. In hieroglyphical paintings these months were also placed in a circle, in the middle of which a face, representing either the sun or moon, was painted. This circle was called a xiuhtlapohualli, or 'count of the year.' Concerning the order in which these months followed one another, and the name of the first month, hardly two authors agree; in the same manner we find three or four various names given to many of the months. It would appear reasonable to suppose that the month immediately following the nemontemi, which were always added at the end of the year, would be the first, and the only difficulty here is to know which way the Aztecs wrote; whether from right to left or from left to right. On the circle of the month given by Veytia, and supposed to have been copied from an original, these five days are inserted between the months Panquetzaliztli and Atemoztli, and counting from left to right, this would make Atemoztli the first month, which would agree with Veytia's statement. But Gama and others decidedly dissent from this opinion, and name other months as the first. I reserve further consideration of this subject for another place in this chapter, where in connection with other matters it can be more clearly discussed, and content myself with simply inserting here a table of the names of the months as enumerated by the principal authors, in order to show at a glance the many variations. I also append to it the different dates given for the first day of the year, in which there are as many contradictions as in the names and position of the months.