We can not reasonably refuse to give some attention to their chronology, even while doubting its value as a means of fixing dates and measuring historical periods. Its method was to count by equal periods of years, as we count by centuries, and their chronology presents a series of periods which carries back their history to a very remote time in the past. Brasseur de Bourbourg says: “In the histories written in the Nahuatl language, the oldest certain date is nine hundred and fifty-five years before Christ.” This, he means, is the oldest date in the history of the Nahuas or Toltecs which has been accurately determined. The calculation by which it is found is quoted from the later portion of the “Codex Chimalpopoca” as follows: “Six times 400 years plus 113 years” previous to the year 1558 A.D. This is given as the date of a division of the land by the Nahuas. The division was made 2513 years previous to 1558 A.D., or in 955 B.C. If this date could be accepted as authentic, it would follow that the Nahuas or Toltecs left Huehue-Tlapalan more than a thousand years previous to the Christian era, for they dwelt a long time in the country of Xibalba as peaceable settlers before they organized the civil war which raised them to power. SOME CONFIRMATION OF THIS HISTORY. That the ancient history of the country was something like what is reported in the old writings seems not improbable when we consider the condition in which the native population was found three hundred and fifty years ago. This shows that Mexico and Central America had been subjected to disrupting political changes caused by violent transfers of supreme influence from one people to another several times in the course of a long history. Such a history is indicated by the monuments, and its traces were noticeable in peculiarities of the native inhabitants of the various districts at the time of the Spanish Conquest. They are still manifest to travelers who study the existing representatives of the old race and the old dialects sufficiently to find them. There were several distinct families or groups of language, and, in many cases, the people represented by each family of dialects were in a state of separation or disruption. To a considerable extent they existed in fragmentary communities, sometimes widely separated.