148 REMARKS on the 



more enigmatical *. The epoch of the precepts, whichM. Baillv 

 has evolved with great ingenuity, goes back no farther than the 

 year 1569, at midnight, between the 17th and i8th of March." 

 From this epoch, the places of the fun and moon are computed, 

 as in the tables of Siam, with the addition of an equation, 

 which is indeed extremely Angular. It refembles that corredlion 

 of the moon's motion, which was difcovered by Tycho, and 

 which is called the annual equation, becaufe its quantity de- 

 pends, not on the place of the moon, but on the place of the 

 fun, in the ecliptic. It is every where proportional to the in- 

 equality of the fun's motion, and is nearly a tenth part of it. 

 The tables of Narfapour make their annual equation only 

 •jV of the fun's : but this is not their only miftake ; for they 

 diredt the equation to be added to the moon's longitude, when 

 it ought to be fubtrac\ed from it, and vice verfa. Now, it is 

 difficult to conceive from whence the laft mentioned error 

 has arifen ; for thoiigh it is not at all extraordinary, that the 

 aftronomers, who conflrucSed thefe tables, fhould miftake the 

 quantity of a fmall equation, yet it is impoffible, that the fame 

 obfervations, which informed them of its exiftence, fliould 

 not have determined, whether it was to be added or fub- 

 tradled. It would feem, therefore, that fomething accidental 

 muft have occafioned this error ; but however that be, an 

 ineq\iallty In the lunar motions, that is found in no fyftem 

 with which the aftronomers of India can have had any com- 

 munication, is atleaft a proof of the originality of their tables. 



17. The tables, and methods, of the Brahmins of Tirvalore, 

 are, in many refpefls, more fmgv\lar tlian any that have yet 



been 



* Thet were explained, or rather decyphered by M. le Gentil in the Memoirs 

 of the Academy of Sciences for 17S4, p. 482, &ic. ; for they were not underftood by the 

 miirionary who fent them to Europe, nor probably by the Brahmins who inftrufled him. 

 M. LE Gentil thinks that they have the appearance of being copied from infcriptions 

 on flone. The minutes and feconds are ranged in rows under one another, not in vertical 

 columns, and without any title to point out their meaning, or their connexion. Thefe 

 tables are publifhed, Mem. Acad. ibid. p. 492, and Aft. Lid. p. 414. 



