48 EVOLUTION AND DOGMA. 



quired an intrepid investigator like Redi, strong in 

 his sense of right and certain in his interpretations 

 of the teachings of experiment, to assert his intellec- 

 tual freedom, and to cope with those who imagined 

 that Aristotle could not err, and that certain meta- 

 physical dicta, which were universally quoted, were, 

 in natural science, to be accounted as so many 

 canons of truth. 



But, notwithstanding the opposition which he 

 excited, Redi was triumphant, and for a long time 

 the theory of spontaneous generation was very gen- 

 erally looked upon as something that had fallen into 

 disrepute. 



Later Researches. . 



But the victory was but temporary. The inven- 

 tion of the microscope, and the discovery of the 

 world of infusorial animalculae, which before had 

 been invisible, resurrected the old theory of abio- 

 genesis, and many eminent naturalists now defended 

 it as strenuously as had any one of its supporters 

 before the experiments of Redi had called it in 

 question. 



Arrong the most eminent champions of the 

 theory of the spontaneous generation of infusory 

 animalcules, were the English naturalist, Needham, 

 and the distinguished French savant, Buffon. As 

 the result of numerous experiments both these 

 observers came to the conclusion that, whatever 

 views might be entertained regarding the origin of 

 the higher forms of animal life, there could be no 

 doubt about the spontaneous production of certain 



