182 MEXICO AND CENTRAL AMERICA 
from the Valley of Mexico, since in their entire recorded 
peregrination they hardly traveled eighty miles. 
Owing to the ineffectiveness of the Mexican time 
count Aztecan chronology is far from fixed. The year 
was known by the day with which it began and as this 
day ran the permutation of four names and thirteen 
numbers the cycle was fifty-two years in length. No 
method of keeping the cycles in their proper order seems 
to have been devised except the laborious one of put- 
ting down every year in sequence whether or not an 
event occurred in it. Unfortunately, not even the 
latter method was used in any far-reaching chronicle 
except the Annals of Quauhtitlan. According to 
different authorities the year 1 Stone which marks the 
historical account in the Aubin Codex was 648, 1064, 
or 1168 in the European calendar, each date differing 
from the others by multiples of fifty-two years. 
The wandering tribes, among which may be men- 
tioned the Chalea, Xochimilea, Tlahnica, Huexotzinea, 
Tepaneca, and Azteca, pushed their way into the region 
of the lakes and made settlements in less desirable loca- 
tions. Meanwhile, they served as vassals to the estab- 
lished tribes. The “peregrinations” relate the suc- 
cession of stops and the length of each stop. ‘The 
Aztecs themselves made twenty or more stops lasting 
from two to twenty years. Finally they took refuge on 
two islands in Lake Tezcoco and lived a miserable exist- 
ence among the reeds. ‘They joined with the Tepane- 
cas and by yeoman service gained their aid and friend- 
ship. 
The date for the foundation of Tenochtitlan (Mexico 
City) is usually given as 1325. About 1350 water 
rights were gained at the spring of Chapultepec. This 
was an important gain because the brackish waters of the 
