颛顼历三事考

A Study on the Zhuanxu Calendar

通过颛顼历的合天年分，求得其测制年代为公元前３７８±３２年。颛项历是在先进的四分历术创立后不久，由三晋的夏历移植到秦国，只是改用了秦国的岁首，属于人正系统，后又传入楚国，为楚人所用，并改用楚国固有的若干月名。颛顼历从创行到汉武帝太初元年止，除秦武王二年一度改变外，始终以十月为岁首。

Appearing in the Warring States period and as an advanced edition of the Xia calendar, the Zhuanxu calendar prevailed for more than 300 years until 104 B.C. during the reign of the Han emperor Wu Di. It witnessed little change except for a very short period in State Qin. It assigned the tenth month of the Xia calendar as the initial month of the year after the Qin tradition. State Chu adopted it but named several months in their own way. This article holds that the compiling time of the said calendar could be c. 378 B. C. (±32 years) ,which is figured out by checking the celestial movement.