6 THE ADVANCE OF SCIENCE 



standstill by the decay and disruption of 

 the Roman Empire, the consequent dis- 

 organisation of society, and the diversion 

 of men's thoughts from sublunary matters 

 to the problems of the supernatural world 

 suggested by Christian dogma in the Mid- 

 dle Ages. And, notwithstanding sporadic 

 attempts to recall men to the investiga- 

 tion of nature, here and there, it was not 

 until the fifteenth and sixteenth centuries 

 that physical science made a new start, 

 founding itself, at first, altogether upon 

 that which had been done by the Greeks. 

 Indeed, it must be admitted that the m3n 

 of the Renaissance, though standing on 

 the shoulders of the old philosophers, 

 were a long time before they saw as much 

 as their forerunners had done. 



The first serious attempts to carry 

 further the unfinished work of Archi- 

 medes, Hipparchus, and Ptolemy, of 

 Aristotle and of Galen, naturally enough 

 arose among the astronomers and the 



