SPONTANEOUS GENERATION 331 



destroy others. After tlie infusion lias been sterilized, 

 the oil- bath is withdrawn, and the liquid^ whose putresci- 

 bilitj has been in no way ajffected by the boiling, is aban- 

 doned to the air of the chamber. 



With such chambers I tested, in the autumn and winter 

 of 1875-76, infusions of the most various kinds, embracing 

 natural animal liquids, the flesh and viscera of domestic 

 animals, game, fish, and vegetables. More than fifty 

 chambers, each with its series of infusions, were tested, 

 many of them repeatedly. There was no shade of uncer- 

 tainty in any of the results. In every instance we had, 

 within the chamber, perfect limpidity and sweetness, which 

 in some cases lasted for more than a year — without the 

 chamber, with the same infusion, putridity and its char- 

 acteristic smells. In no instance was the least countenance 

 lent to the notion that an infusion deprived by heat of its 

 inherent life, and placed in contact with air cleansed of 

 its visibly suspended matter, has any power to generate 

 life anew. 



Eemembering then the number and variety of the in- 

 fusions employed, and the strictness of our adherence to 

 the rules of preparation laid down by the heterogenists 

 themselves; remembering that we have operated upon the 

 very substances recommended by them as capable of fur- 

 nishing, even in untrained hands, easy and decisive proofs 

 of spontaneous generation, and that we have added to 

 their substances many others of our own — if^this pretended 

 generative power were a reality, surely it must have mani- 

 fested itself somewhere. Speaking roundly, I should say 

 that in such closed chambers at least five hundred chances 

 have been given to it, but it has nowhere appeared. 



The argument is now to be clinched by an experiment 



