284 
ing and waning of the Moon ; they reckon the 
weeks by the quarters, without having particular 
names for the days of the week.” But Acosta, 
better informed than Garcilasso ; and who, to- 
ward the end of the sixteenth century, com- 
posed at Peru the first books of his Physical Geo- 
graphy of the New Continent; says clearly, that 
neither the Mexicans, nor the Peruvians, were 
acquainted with the small period of seven days ; 
for this period,” adds he, does not depend 
more on the course of the Moon, than on that 
of the Sun. It owes its origin to the number of 
the planets*.” 
If we reflect an instant on the system of the 
Peruvian calendar, we shall be aware, that, 
though the phases of the Moon change nearly 
every seven days, this cycle of seven days does 
not correspond with any accuracy to the phases 
of the Moon in several consecutive lunar months. 
The Peruvians, according to Polo, and all the 
writers of those times, had years (huata) of 865 
days, regulated, as we shall see farther on, by 
solar observations made month after month at 
the city of Cuzco. The Peruvian year was divid- 
ed, as were almost all the years of the nations of 
Eastern Asia, into twelve Moons, qidlla^ the syno- 
dical revolutions of which finished in 354 days, 
^ Acosta, Hisloria natural y moral tie las Tndias. Lib. C, 
C. 3, ed. of Barcelona, 1591, p. 260. 
