114 ON THE REVOLUTIONS OF 



thus all confirms the idea that the great reputation of the Chaldeans 

 was given to them, in more modern times, by their unworthy succes- 

 sors, who, under the same name, sold, throughout the Roman empire, 

 horoscopes and predictions ; and who, to gain more credit, attributed 

 to their rude ancestors the honour of the discoveries of the Greeks. 



As to the Indians, it is well known that Bailly, thinking that the 

 epoch which is Used as a period of departure in some of their astrono- 

 mical tables had been really observed, has attempted thence to deduce 

 a proof of the remote antiquity of this science amongst this people, 

 or at least in the nation which had bequeathed its knowledge to them. 

 But the whole of this system, so laboriously conceived, falls to the 

 ground of itself, now that it is proved that this epoch was subsequently 

 adopted on calculations made backwards, and the result of which was 

 incorrect *. 



M. Bentley has discovered that the tables of Tirvalour, on which 

 particularly the assertion of Bailly was founded, must have been cal- 

 culated about 1281 after Christ (540 years since) ; and that the Surya- 

 Siddhanta, which the Brahnains regard as the most ancient and scien- 

 tific treatise on astronomy, and which they pretend was revealed more 

 than twenty millions of years ago, could not have been composed 

 until about 760 years since f. 



The solstices and equinoxes marked in the Pouranas, and calculated 

 according to the positions which were assigned to them in the signs 

 of the Indian zodiac, have had a very remote antiquity assigned to 

 them. A more exact study of these signs, or nacchatrons, has lately 

 shown M. de Paravey that reference is only made to solstices of 

 twelve centuries before Christ. This writer, at the same time, states 

 that the place of these solstices is so indefinitely fixed, that we cannot 

 decide on it nearer than two or three hundred years. Those of 

 Eudoxus and Tcheou-Kong are the same :|:. It is confidently as- 

 serted that the Indians do not make observations, and have no instru- 

 ments necessary for that purpose. M. Delambre agrees with Bailly 

 and LegentU, that they have processes of calculations which, without 

 proving the antiquity of their astronomy, at least show its originality § ; 

 and this conclusion cannot be extended to their sphere, for in- 



* See Laplace's Expose du Systeme du Monde, p. 330 ; and the Memoir of M. 

 i)avis on the Astronomical Calculations of the Indians. Mem. de Calcutta, v. 2, p. 

 225, 8vo. edit. 



f See Mem. of Bentley, on the Antiquity of Surrya-Siddhanta. Mem. de Calcutta, 

 V. vi, p. 540 ; and on the Astronomical Systems of the Indians, ib. v. viii, p. 165 

 of the 8vo. edit. 



J Manuscript Memoirs of M. de Paravey, on the Sphere of Upper Asia. 



§ See the profound treatise on the Astronomy of the Indians, in the History of 

 Ancient Astronomy, by M. Delambre, v. I, p. 400 — 556. 



