ASTRONOMICAL SCIENCE IN THE ANCIENT ORIENT 209 



already long iu practical use, so as to give a layman like Mencins 

 strong confidence in its reliability, and secondly, that the success of 

 the astronomers in preparing a good luni-solar calendar must have 

 aroused in the general public a keen interest in the science in 

 general. 



The year 104 B.C. is an important epoch in the history of 

 astronomy in China. A large-scale conference was held in order to 

 discuss the problem of calendar-reform, and after some controversy, 

 it resulted in the acceptance of an official calendar system by the 

 name of the T'oA-cli'u-Ii i^^)§: (" The first calendar system "). It is 

 indeed the first calendar system sanctioned as official, and after that 

 all the succeding calendar system, about 50 in number until recently, 

 being equally sanctioned as official reformations, are always fully 

 described in the oflScial records of the dynasties. They are all of 

 course according to the luni-solar system. 



As to the T'ai-cli'u-U :i:^M itself, although the records are not 



without ambiguity, and hence have been at times much debated, yet 



it seems to me certain that it is in essence nothing but the calendar 



system Scm-t'ting-Ii ^^]^, ftiHy described in the Han-sJm '^^ 



(history of the Han dynasty). We see that it is therein assumed that 



385 



the length of a year = 365 =365.2502. 



"" *^ 1539 



43 



the length of a month = 29 =29.53085, 



'^ 81 



making 385 43 



365 xl9=29 x235, 



1539 81 



that, in the 11th month of the year preceding 104 B.C., 



the winter-solstice, the new-moon (conjunction), 



the day cliia-tzu Ep-^, midnight, and also an eclipse, 



— all these happened just to coincide with one another, and that 



hence this coincident epoch ought to be taken as the beginning of 



the calendar system. 



It may be noticed here that theoretically the approximate period 



of eclipses might be taken as any one of the series, 88 135 223 358 



months ; and that here in the T^ai-cJi'u-K, the period of 



135 months is used, while in the Occident the period of 223 months 



was known under the name of the Chaldean Saros. This fact gives 



us strong evidence that Chinese astronomy was free from Western 



influences at least until the date 104 B.C. 



