1881.] Zhe Maya Calendar and the Age of MS. Troano. 767 
AN ATTEMPT TO RECONCILE THE DIFFERENCES 
BETWEEN AUTHORITIES IN REFERENCE TO 
THE MAYA CALENDAR AND CERTAIN 
DATES; ALSO TO DETERMINE 
THE AGE OF THE MANU- 
SCRIPT TROANO. 
BY PROFESSOR CYRUS THOMAS. 
‘y my former paper (AMERICAN NaturaList for August, 1881), 
I reached the following conclusions : 
First—That the Ahau or Katun consisted of twenty-four 
years. 
Second.—That but twenty of these years were usually counted. 
Third.—That the grand cycle consisted of 312 years. 
Fourth.—That the cycles began with the year 1 Cauac, or in 
other words that the Cauac column in the table of years should 
Stand at the left. 
Two important points yet remain to be determined before we 
are in a condition to compare Maya dates with those of the 
Christian era: 
First—The position of the different Katunes according to their 
numbers in the grand cycle. 
econd.—Some one year of the Christian era that corresponds 
with some one year of a given Katun, or, in other words, to 
determine one or more contemporaneous dates of the two 
systems, 
Before entering upon the discussion of the topic mentioned in 
the title to this paper, I wish to present the following additional 
Proof that the year series commenced with a Cauac year, as this 
‘Sa point which must be settled before we can feel certain in 
Tegard to any comparison made between dates of the two 
Systems, 
In the manuscript discovered by Perez and translated into 
English by Stephens, we find the following statement: 
_ In the 13th Ahau, Chief Ajpula died. Six years were want- 
rs to complete the 13th Ahau. This year was counted towards 
= ‘one of the wheel and began on the 4th Kan. Ajpula died 
18th day of the month Zip, on g Ymix; and that it may 
demain 2 numbers, it was the year 1536, sixty years after the 
€molition of the fortress.” 
As the years could only begin with one of the four days, 
