722 Notes on the Codex Troano, and Maya Chronology. (Sept., 
that it occurred not only in the 6th year from the close of the 
Ahau, but he also gives it in the Kin Katun reckoning as the 
year 4 Kan. Now it is obvious that if Ahau xi is the first of 
the greater cycle, the number of the year referred to should be 
the same as the number of the year 4 Kan in the lesser cycle— 
a coincidence which could not occur except in the first Ahau of 
the Katun. In fact, 4 Kan is the 18th year of the Kin Katun; 
and of course 24 — 6 = 18, the year of the Ahau. 
This leads to the result that the coincidence above referred to, 
which marked the beginning of the greater cycle, occurred July 
16, 1517, on which day, for the first time for 312 years, the cuf-__ 
rent Ahau und Kin Katun both began on the day 1 Kan. 
With this date thus definitely fixed, it would be easy to con- 
struct a table showing the correspondences of the Maya and 
Christian systems of reckoning. I shall pass, however, to its 
application to the Codex Troano. 
Leaving aside the opinion of the Abbé Brasseur that this man- 
uscript is a sort of geological treatise, and that of Mr. Bollaert 
that it is a history, all unprejudiced students have agreed that a 
portion of it at least is a calendar—what the Mayas called tzolan 
Katun, the arrangement of the Katuns or divisions of time, and 
probably also a ¢zo/anzé, ritual. The left hand columns of the 
four plates numbered xxi11, xxi, xx1, xXx, as has been noted by 
Professor Thomas, enumerate a series of 52 years beginning with 
10 Cauac, which is the 36th year of the Kin Katun. Could we 
find anywhere on these plates the number of the Ahau, there 
would be no difficulty in fixing the exact date of the manuscript. 
I have no doubt that Professor Thomas is right in believing that 
the Ahau is indicated in the upper compartment of Plate XxUI, 
and I had repeatedly sought to make it out there before seeing 
his article ; but unless it is the figure two in red at the top of the 
column of numbers to the right of the figures in blue, | cannot 
discern it. Assuming that the date is Ahau 11, and the year ” 
Cauac, it is obvious from the method of calculating above given 
that the year with which this calendar begins is that which cor- 
responds to July 16, 1500-1501, and that it ends on the year 9 
Ix, Ahau x1—July 16, 1552-1553. . 
Passing by various other considerations of interest in connec” 
tion with the Codex, I shall offer one suggestion which, so far a5 
I know, has not heretofore been made. 
