IOv, REMARKS on the 



A formula for computing the quantity of this inequality, has 

 been given by M. de la Place, which, though only an approxima- 

 tion, being derived from theory, is more accurate than that which 

 Mayer deduced entirely from obfervation * ; and if it be taken 

 inftead of Mayer's, which laft, on account of its fimplicity, I 

 have employed in the preceding calculations, it will give a 

 quantity fomewhat different, though not fuch as to affect the 

 general refult. It makes the acceleration for 4383 years, dated 

 from the beginning of the Calyougham, to be greater by 17', 39", 

 than was found from Mayer's rule, and greater confequently by 

 j6\ 32", than was deduced from the tables of Chrifnabouram. 

 It is plain, that this coincidence is dill near enough to leave the 

 argument, that is founded on it,!* in poffemon of all its force, 

 and to afford a ftrong confirmation of the accuracy of the 

 theory, and the authenticity of the tables. 



That obfervations made in India, when all Europe was 

 barbarous or uninhabited, and investigations into the moft fub- 

 tle effects of gravitation made in Europe, near five thoufand 

 years afterwards, fhould thus come in mutual fupport of 

 one another, is perhaps the moft ftriking example of the pro- 

 grefs and viciffitude of fcience, which the hiftory of mankind 

 has yet exhibited. 



29 This, however, is not the only inftance of the fame 

 kind that will occur, if, from examining the radical places and 

 mean motions in the Indian aftronomy, we proceed to confider 

 fome other of its elements, fuch as, the length of the year, the 

 inequality of the fun's motion, and the obliquity of the eclip- 

 tic, and compare them with the conclufions deduced, from the 

 theory of gravity, by M. de la Grange. To that geometer, 

 phyfical aftronomy is indebted for one of the moft beautiful of 

 its difcoveries, viz. That all the variations in our fyftem are 

 periodical ; fo that though every thing, almoft without excep- 

 tion, 



* Mem. Acad, des Scien. 1786, p. 260. 



