542 ox THE ANTIQUITY OF 



back, are fixed on as epochs, at which the planets 

 are assumed to fall into a line of mean conjunction 

 with the Sun, in the beginning of Aries. From the 

 points of time, so assumed as epochs, the Hindu 

 astronomer carries on his calculations, as if they had 

 been settled so by actual observation ; and ■ deter- 

 mines the mean annual motions, which he mustemploy 

 in his system, from thence, as will give the positions 

 of the planets in his own time ; as near as he is able 

 to determine the same by observation. 



5. In fixing on these epochs, the first Hindu 

 astronomers took the precaution to throw them so 

 far back into antiquity, that the difference between 

 the assumed, and real places of the planets, whatever 

 they might be at that time, would, when divided by 

 the number of years expired from thence, in a man- 

 ner vanish ; or at least become too inconsiderable, 

 to affect the mean annual motions of the planets, 

 deduced from thence for several years. For, it is 

 easy to perceive, thai a point of time, may be fixed 

 on so far back, that the mean annual motions of the 

 planets to be from thence deduced, ^upon a supposi- 

 tion of their being then in aline of mean conjunction 

 in the beginning of Aries) shall give the real positions 

 -'of the planets at present, agreeing with observations: 

 and yet, the mean annual motions, so deduced, shall 

 not differ from the real mean annual motions, above 

 ^ny assignable quantity, however small. 



6. For, let an epoch of mean conjunction, be 

 assumed at only "the distance of 64 8000 years ago ; 

 withont troubling ourselves at all with the real posi- 

 tions of the planets at that time, (which it would be 

 impossible to know) now since the greatest possible 

 .difference that can ever happen, at any proposed 

 time between the assumed, and real place of a planet, 



cannot 



