[ 54 ] Thibaut places the period somewhere in the fifth century A. D. It is, however, strange that he has omitted to discuss the bearing of the Dhruvas of the seven stars he has found in the old Sürya- Siddhánta. Omitting Aslesha which I cannot identify with certainty, the mean general precession of the remaining six amounts to about 24'. This implies, then, that astronomy as & science began to be cultivated in India in the second century A. D. at the latest. We have already dwelt rather too long on the determination of the starting point. But considering the importance of the question in settling one of the fundamental preliminaries to any possible revision of our current almanacs, a word or two more on the subject may be excused. Chandrasekhara gives two methods for determining the starting point. One is based upon a verse of the modern Súrya- Siddhánta, which he takes to mean that the declination-circle passing through the pole-star marks the junction between Aries and Pisces (XII. 61). He further cites his authority for thus interpreting the verse from Brahma-Jámala. I am inclined to believe that he is mistaken in thus inter- preting the s loka of the Súrya-Siddhánta,* though I have not seen Brahma-Jámala, nor have I an opportunity of doing so now. Taking, however, the rule for granted, it will be seen that the Dhruva of the star was 21° 42' in Saka 1816. But. The particular bloka of the Súrya-Siddhanta is, भचक्रं भुवयोजिमादिप्तं प्रवामिलैः । quinta ag 41 4€1971 XII.73 Digitized by Google
