Archdeacon Pratt on Chinese Astronomical Epochs. 7 



whether there is any special reason for so remote an epoch as 

 2357 B.C. being selected. I can see no special reason. (1) 

 Even if X Orion is not rejected, it will be seen that the width of 

 the third mansion is 2° 23' and 1° 58' at those two later dates, 

 and these are not so inferior to 2° 43', the width in 2357 B.C., 

 as to induce any great preference for that epoch. (2) By com- 

 paring the columns of decimations in Tables I. and III., it will 

 be seen that the twenty-eight stars lie very much alike with 

 reference to the equators of the three epochs, without any decided 

 advantage for 2357 B.C. In all of them the mid-line is south of 

 the equator j the distance is 2° 28', 2° 26', 2° 48' in the three 

 cases. (3) M. Biot points out that the arrangement of stars 

 chosen by the Chinese is equatorial, and not ecliptical ; and he 

 well illustrates this by showing that « Hydrse has been chosen, 

 though only of the second magnitude, as the eighth star in pre- 

 ference to the much brighter star Regulus in the same hour- 

 angle, but on the ecliptic and about 24° from the equator. But 

 he departs from this idea when he draws an argument for his 

 ancient epoch from the circumstance that 77 in Pleiades is the 

 first of the twenty-eight stars, and that therefore when the 

 system was chosen that star must have been the vernal equinox. 

 The Pleiades, in their sevenfold group, are so conspicuous and 

 marked an object, that it is very easy to understand that, being 

 chosen as one of the twenty-eight determining stars, they should 

 be fixed upon, for that reason, as the point of departure. At 

 the three dates in my Tables, the declination of 7? is onlv 3° 10', 

 7° 53', 11° 2V; the largest of which is smaller than that of 

 twelve of the twenty-eight stars as laid down by M. Biot for 

 2357 B.C. In passing backwards to obtain as great a w r idth as 

 possible for his third mansion, he seems to have stopped short at 

 7} in Pleiades for no other reason than that, being first of the 

 equatorial series, it might also be the equinox; whereas by 

 going further back he might have somewhat further widened 

 his third mansion. (4) M. Biot also observes that four of the 

 chosen stars, the 1st, 8th, 15th, and 22nd (see Table II.), fall 

 very near the equinoxes and solstices of 2357 B.C., and that this 

 is an argument in favour of that epoch. But my Table IV. shows 

 that in 1100 B.C. four others of the twenty-eight stars, also at 

 equal intervals in point of number, viz. the 7th, 14th, 21st, and 

 28th, were still nearer to the equinoxes and solstices. So that 

 no argument can be drawn from this source in favour of his 

 epoch : rather the contrary. He says that the four stars he 

 names are mentioned in the Chou-king*, an ancient work on 



* For what is known of this work Chou-king, or Sboo-king, see Encyc. 

 Brit., word China, p. 640 : also see " History of Astronomy " in 'Library 

 of Useful Knowledge.' 



