124 DISSERTATION SECOND. [pam i. 



great. During the thirteenth and fourteenth centuries, it 

 was taught in the universities of Italy, and professors were 

 appointed, at Padua and Bologna, to instruct their pupils in 

 the influence of the stars. Everywhere through Europe 

 the greatest respect was shown for this system of imposture, 

 ami they who saw the deceit most clearly, could not always 

 avoid the disgrace of being the instruments of it. Astro- 

 nomy, however, profited by the illusion, and was protected 

 for the great assistance which it seemed to afford to a sci- 

 ence more important than itself. 



Of those who cultivated astronomy, many were infected 

 by this weakness, though some were completely superiour 

 to it. Alphonso, the King of Castile, was among the lat- 

 ter. He flourished about the middle of the thirteenth 

 century, and was remarkable for such freedom of thought, 

 and such boldness of language, as it required his royal 

 dignity to protect. He applied himself diligently to the 

 study of astronomy ; he perceived the inaccuracy of Ptole- 

 my's tables, and endeavoured to correct their errours by 

 new tables of his own. These, in the course of the next 

 age, were found to have receded from the heavens, and it 

 became more and more evident that astronomers had not 

 yet discovered the secret of the celestial motions. 



Two of the men who, in the fifteenth century, contri- 

 buted the most to the advancement of astronomical science, 

 Purbach and Regiomontanus, were distinguished also for 

 their general knowledge of the mathematicks. Purbach 

 was fixed at Vienna by the patronage of the Emperour 

 Frederick the Third, and devoted himself to astronomical 

 observation. He published a new edition of the Almagest, 

 and, though he neither understood Greek nor Arabick, his 

 knowledge of the subject enabled him to make it much 

 more perfect than any of the former translations. He is 

 said to have been the fir-it who applied the plummet to 



