390 



eclipses of the Sun on the 23d of February, 1477, 

 and the 7th of June, 1481, which are indicated 

 in the hieroglyphical annals; on several me- 

 morable periods of the conquest; and on the 

 days, when, according to the Mexican records, 

 the Sun passes the zenith of Tenochtitlan ; seem 

 to prove, that this error of three days did not 

 take place ; and that at the beginning of the 

 sixteenth century, as we have before observed, 

 the dates of the Azteck calendar were more ac- 

 cordant with the days of the solstices and equi- 

 noxes, than those of the Spanish calendar. 



Without knowing the exact length of the year, 

 the Mexicans would have been enabled from 

 time to time to rectify their calendar, as they 

 learned from gnomonic observations, that, in 

 the first year of the cycle, the equinoxes of spring 

 and autumn were some days distant from 7 ma- 

 linalli, and from 9 cozcaquauhtli. The Peruvi- 

 ans of Cuzco, whose year was lunar, regulated 

 their intercalation, not by the shadow of gno- 

 mons, which they however very assiduously mea- 

 sured, but by marks placed in the horizon, to 

 denote where the Sun rose and set on the days 

 of the solstices and equinoxes. A periodical and 

 exact intercalation, such as that which has been 

 known by the Persians since the eleventh cen- 

 tury, is no doubt preferable to those sudden 

 changes, which are denoted by the title of re- 

 forms of the calendar ; but a nation, which for 



