114 VITALISM AND SCHOLASTICISM 



taneous generation was once more consigned 

 to oblivion, or at least to comparative 

 oblivion, for it has always possessed certain 

 adherents. 



Amongst these the most important was the 



Pouchet elder Pouchet who in 1858 declared that he 

 had seen the spontaneous production of in- 

 fusoria in a sterilised fluid which had been 

 exposed only to air also deprived of all germs. 

 The discussion on this subject became so active 

 that the French Academy of Sciences in 1860 

 offered a prize for the solution of the matter. 



Pasteur It was then that Pasteur* came upon the scene 

 and made the classical experiments which will 

 always be associated with his name. First of 

 all he showed, as Spallanzani had done before 

 him, that infusions in which life would have 

 appeared if they had not been sterilised, or if^ 

 after sterilisation, they had been left exposed 

 to the air, would, if boiled for a sufficiently 

 long time, and retained in closed vessels, re- 

 main permanently without any signs of life. 

 Then it was argued that this was because the 

 fluid was deprived of fresh air. To this Pasteur 

 retorted by the further experiment of filtering 

 the air which was admitted to the sterilised 

 fluid through a wad of cotton- wool. He even 

 showed that if the flask in which the sterilised 



* 1822-1895. For an account of his life see " Twelve 

 Catholic Men of Science," C.T.S., 19H. 



