ASTRONOMICAL SCIENCE IN THE ANCIENT ORIENT 



211 



side, and to Japan on the other, the introduction of Western astrono- 

 my in the T^ang (618-906 A.D.) and the following dynasties, etc., 

 are all interesting topics for study, which may be investigated with 

 comj)arative ease. All these we refer to future study. 



: Assumed age 



of Yao and Shun 



2000— 



1000- 



B.C. 



0- 



A.D. 



.Assumed beginning 



of Chou dvnastv 



_ Middle of si^ 



Ch'nn cli'iu Period 



_Middle of 



Chan kuo Age 



_T'ai chu 



in Han dvnastv 



>fc 



Pure Lunar Calender in use 



t 



i 

 Luni-Solar Calendar in use 



/ Ta-lnio\ 

 yTs'aii ) 

 ^Pei-tou 



Calendar adjusted by 



occasional ohs. of ch^en 



(28 hsiii System) 



(Gnomon) 



Calendar System in preparation 



Definite Calendar System in use 



i 



Official Calendar Svsteni in use 



