377 



admitted a far more simple mode of intercala- 

 tion, than that of the Greeks and Romans before 

 the introduction of the Merkidinus. If we cast 

 our eyes upon the intercalations used among 

 different nations, we see that some permit the 

 hours to accumulate till they form a whole day, 

 while others neglect the intercalation till the 

 supplementary hours form a period equal to one 

 of the great divisions of their year. The first 

 mode of intercalation is that of the Julian year, 

 the second is that of the ancient Persians, who 

 added, every one hundred and twenty years, a 

 whole month of thirty days to a year of twelve 

 months, and so that the intercalary month ran 

 through the whole year in 12 X 120 or fourteen 

 hundred and forty years *. The Mexicans have 

 evidently followed the system of the Persians ; 

 they retained the vague year, till the supplemen- 

 tary hours formed a half lunation, and they in- 

 tercalated consequently thirteen days in every 

 ligature, or cycle of fifty-two years. Hence it 

 followed, as we have already observed, that 

 each ligature contained ~, or one thousand four 

 hundred and sixty- one small periods of thirteen 

 days. The Mexican year began at the commence 

 ment of the xiuhmolpilli, on the day which corres- 

 ponds to the 9th of January of the Gregorian 

 calendar. The fifth, ninth, and thirteenth years 



* Ideler, Hist. Unters., s. 379. 



