SEQUEL TO THE EPOCH OF HIPPARCHUS. 219 



Sect. 4. Period from Hipparchus to Ptolemy. 



WE have now to speak of the cultivators of astro- 

 nomy from the time of Hipparchus to that of 

 Ptolemy, the next great name which occurs in the 

 history of this science ; though even he holds place 

 only among those who verified, developed, and 

 extended the theory of Hipparchus. The astro- 

 nomers who lived in the intermediate time, indeed, 

 did little, even in this way ; though it might have 

 been supposed that their studies were carried on 

 under considerable advantages, inasmuch as they 

 all enjoyed the liberal patronage of the kings of 

 Egypt 17 . The " divine school of Alexandria," as it 

 is called by Synesius, in the fourth century, appears 

 to have produced few persons capable of carrying 

 forwards, or even of verifying, the labours of its 

 great astronomical teacher. The mathematicians 

 of the school wrote much, and apparently they ob- 

 served sometimes; but their observations are of 

 little value : and their books are expositions of the 

 theory and its geometrical consequences, without 

 any attempt to compare it with observation. For 

 instance, it does not appear that any one verified 

 the remarkable discovery of the precession, till the 

 time of Ptolemy, 250 years after; nor does the 

 statement of this motion of the heavens appear in 

 the treatises of the intermediate writers ; nor does 

 Ptolemy quote a single observation of any person 



17 Delamb. A. A. ii. 240. 



