THE UNIVERSE. DISCOVEEIES IN THE CELESTIAL SPACES, 307 



remark it may be noticed, that astrology, and amendments 

 in the Calendar, were long chiefly efficacious in obtaining for 

 astronomy the protection of secular or ecclesiastical power ; 

 as chemistry and botany were long regarded solely as sub* 

 servient to medicinal knowledge. 



The free and powerful language employed by Copernicus, 

 the evident outpouring of deep internal conviction, suffi- 

 ciently refutes the assertion, that the system which bears his 

 immortal name was proposed as an hypothesis convenient 

 to calculating astronomers, but which might very well be 

 without foundation. " By no other arrangement/' he ex- 

 claims, with inspired enthusiasm, " have I been able to dis- 

 cover so admirable a symmetry of the universe, so harmo- 

 nious a combination of orbits, than by placing the light of 

 the world (lucernam mundi), the sun, as on a kingly throne, 

 in the midst of the beautiful temple of nature, guiding 

 from thence the entire family of circum-revolving planets 

 (circumagentem gubernaiae astrorum familiam) ." ( 465 ) Even 

 the idea of universal gravitation or attraction (appetentia 

 qusedam naturalis partibus indita) towards the centre of the 

 world (centrum mundi), the sun, inferred from the force of 

 gravity in spherical bodies, appears to have floated before 

 the mind of this great man, as is shewn by a remarkable 

 passage ( 466 ) in the 9th chapter of the 1st book of the 

 Bevolutions." 



! In passing in review the different stages of the develop- 

 rnent of cosmical contemplations, we discover from the 

 earliest times more or less obscure anticipations of the 

 attraction of masses, and of centrifugal forces. Jacobi, in his 

 investigations on the mathematical knowledge of the Greeks, 

 (which are unfortunately still in manuscript), dwells with 



