192 THEORY OF THE EARTH. 



who is comparatively modern, and who lived at a 

 long period after the establishment of the fixed 

 year of Alexandria, must have confounded the 

 epochs. Diodorus * and Strabo ( only attribute 

 such a year to the Thebans ; they do not say 

 that it was in general use, and they themselves 

 did not live till long after Herodotus. 



Thus the Sothian or great year must have been 

 a comparatively recent invention, since it results 

 from the comparison of the civil year with this 

 pretended heliacal year of Sirius ; and it is for 

 this reason that it is only spoken of in the works 

 of the second and third century after Christ J, and 

 that Syncellus alone, in the ninth, seems to cite 

 Manetho as having made mention of it. . 



Notwithstanding all that is said to the con- 

 trary, the same opinion must be formed of the as- 

 tronomical knowledge of the Chaldeans. It is na- 

 tural enough to think, that a people who inhabi- 

 ted vast plains, under a sky perpetually serene, 

 must have been led to observe the course of the 

 stars, even at a period when they still led a wan- 

 dering life, and when the stars alone could direct 



Bibl. lib. i. p. 46. t Geogr. p. 182. 



J See regarding the probable newness of this period the 

 excellent dissertation of M. Biot, in his Researches respect- 

 ing several points of the Egyptian Astronomy, p. 148 et 



sea. 

 " 



