﻿10 Cincinnati Society of Natural History. 



for their proper intelligence, that one should know the manner in 

 which the Mexicans divided their time, and their calendars and 

 their " Tonalamatl, " and especially in order to be able to com- 

 prehend perfectly the interpretation of the second stone, we 

 will divide our explanation into four sections or parts. The 

 first will contain the general method of observing and distributing 

 time into fixed periods of cycles, years, months and days, and 

 their aliquot parts, in all that regards their weeks, or rather trecenas, 

 of which they composed their Tonalamatl, in which you will find 

 an account of the first of the two stones we have found (z. e. the 

 Statue). The second part will be the explanation of the idol stone 

 {i. e. the Statue). In the third will be contained in brief, the com- 

 putation by which they governed themselves, depending on the 

 movement of the sun and moon, for the celebration of their fes- 

 tivals, for their commercial affairs, and for other uses, both civil 

 and political, and we will establish the veritable calendars, refuting 

 as false, erroneous, and absurd all other systems which certain 

 authors have invented, as being entirely opposed to what the rela- 

 tion of the Indians themselves have established, and to the natu- 

 ralness and invariable method which they observed in all matters 

 relating to their government. We will harmonize the two kinds 

 of calendars with themselves and with ours. We will establish the 

 commencement of their year, with other details relating to their 

 chronology — and finally, the fourth part will be an exact account 

 of the carvings and symbols contained on the second stone, and of 

 the chief purposes for which the Mexicans made use of it. But, 

 since after the conclusion of this work, there have appeared other 

 notices and circumstances which have more interested the curiosity 

 of the public; in order not to deprive the people of them — it 

 seemed to us most proper to insert them in the following 



ADDENDA. 



When it was announced in the Gazeta De Mexico of the 16th of 

 August, 1 79 1, that this book was concluded, inviting persons who 

 were interested in such matters to subscribe, I was then ignorant 

 of the important proceedings taken by His Excellency Senor Virey, 

 Count of Rivilla Gigedo, and by the Senor Superintendent, Don 



