APPENDIX. 



367 



In all thofe periods an art is difcovered not lefs admira- 

 ble than that of our indiftions, cycles, &c. The period 

 of civil weeks was contained exactly in their civil and af- 

 tronomical month ; the latter had fix, the former four, 

 and the year contained feventy-three complete weeks ; in 

 which particular our method is excelled by the Mexican ; 

 for our weeks are not contained exa6lly in the month, 

 nor in the year. The period of religious weeks was 

 contained twice in their religious month, and twenty- 

 eight times in the year ; but in the latter there remain- 

 ed a day over, as there is in our weeks. From the peri- 

 ods of thirteen days, multiplied by the twenty charadiers 

 of the month, the cycle of two hundred and fixty days 

 was produced, of which you have made mention ; but 

 as there remained a day over the twenty-eight religious 

 weeks of the folar year, there arofe another cycle of two 

 hundred and fixty days, in fuch a manner, that the 

 Mexicans could, from the firll: day of every year, diftin^ 

 guifti what year it was. The period of civil months, mul- 

 tiplied by the number of days, (that is eighteen by 

 twenty), and the period of lunar months, multiplied by 

 the number of days, (that is, twelve by thirty), give 

 the fame product, or the number three hundred and 

 fixty ; a number certainly not lefs memorable, and in 

 ufe among the Mexicans than am.ong the moft ancient 

 nations ; and a number, which from time immemorial, 

 has ruled in geometry and aftronomy, and is of the ut- 

 moft particularity on account of its relation to the circle, 

 which is divided into three hundred and fixty parts, or 

 degrees. In no nation of the world do we meet with 

 any thing fimilar to this clear and difi:in61: method of Ca- 

 lendar. From the fmall period of four years, multiplied 

 by the above mentioned cycle of two hundred and fixty 



years. 



