The various Nahua and Maya tribes of Mexico and Central America had reached about the same stage of development. But their calendar system is so similar that it affords a strong argument of the original unity of these people.65 All of the civilized tribes had months of twenty days each, and each of these days had a separate name, which was the same for every month of the year. This period of twenty days was properly their unit of time reckoning. It is true they had smaller divisions,66 but for all practical purposes, they were ignored. As none of these tribes possessed the art of writing, they had to represent these days by means of hieroglyphics. The following table shows the Mexican and Maya days, the meaning of each, and the pictorial sign by which they were represented. We must notice that the Maya hieroglyphics look more arbitrary, more conventional than the Mexican. This is interesting, because some of our scholars now believe the Mayas were the inventors of the calendar. Their hieroglyphics, therefore, as being the older of the two, should appear more conventional. In the Mexican hieroglyphics for the days, we can still trace a resemblance to the natural objects they represent; in the Maya hieroglyphics, this resemblance has disappeared.
It is not out of place to theorize as to the facts already mentioned. The first thing that strikes us is that they should have chosen twenty days for a unit of time. There must have been some reason lying back of this selection. It would have been more natural for them to have chosen a number of days (say thirty) more nearly corresponding to the time from one new moon to another. Whether we shall ever learn the reason for choosing this number of days is doubtful; but Mr. Bandelier has given us some thoughts on this subject, which, though he is careful to state are not results, but mere suggestions, seem to us to have some germs of truth, the more so as it is fully in keeping with Indian customs.
He points out that many of the names for these days mean the same as the names of the gens in the more northern Indian tribes. Thus seven of the days have the same meaning as the names of seven of the nine gens of the Moqui tribe in Arizona. He, therefore, suggests that the names of these twenty days are the names of the twenty gens of the aboriginal people from whom have descended the various civilized tribes under consideration. Indeed, this is expressly stated to be the method of naming the days adopted by the Chiapanecs, one of the tribes in question.57
As soon as the people commenced to take any observation at all, they would perceive that it took just about eighteen of these periods of twenty days to make a year. So the next step appears to have been the division of the year into eighteen months. These months received each a name, and were of course designated by a hieroglyphic. The names of the Mexican months seem to have been determined by some of the feasts happening therein. There is great diversity among the early writers both as to the names of these months, and the order in which they occur, as well as by the hieroglyphics by which they are represented.68 It does not seem worth while to give their names and meaning. We give a plate showing the name, order in which they occur, and hieroglyphic symbol of the Maya months. In point of fact, the months were very little used, as we shall soon see it was not necessary to name the month to designate the day; but of that hereafter.
But it would not take these people very long to discover that they had not hit on the length of a year. Eighteen months, of twenty days each, make only three hundred and sixty days; so the next step would be to add on five days to their former year. As these days do not make a month, they were called the nameless days. They were considered as being unlucky—no important undertaking could be commenced on one of them. The child born therein was to be pitied. But we will see that the expression, “nameless days” was hardly the case among the Mayas, though it was among the Mexicans.
Perhaps this will be as good a place as any to inquire whether they had exact knowledge of the length of the year. As every one knows, the length of the year is three hundred and sixty-five and one quarter days, or very nearly; and for this reason we add an extra day to every fourth year. We would not expect to find this knowledge among tribes no farther advanced than we have found these to be. If, as our scholars suspect, the Maya be the one from which the others were derived, they would be apt to possess this knowledge, if known. Perez, however, could find no trace of it among them.69 Many authors have asserted that the Mexicans knew all about it. Some say they added a day every four years; others, that they waited fifty-two years, and then added thirteen days; and some, even, give them credit for still closer knowledge, and say they added twelve and one-half days every fifty-two years.70 Prof. Valentine, who has made their calendar system a special study, concludes that they knew nothing at all about the matter.71