CO 



CONDITIONS FAVOURlNa FERMENTATION. 



and admitted that fermentative processes were not necessarily 

 initiated by independent living organisms, since, following in the 

 direction indicated by the researches of MM. Lechartier and 

 Bellamy*, he had convinced himself that their role might be 

 taken by the cell-elements of higher organisms when these exist 

 under certain abnormal conditions. 



In 1876 M. Pasteur t made a further concession, striking still 

 more at the root of his original doctrine of 1862, since, after 

 having repeated some investigations of M. Musculus X, he ad- 

 mitted that urine contained a separable chemical ferment, capable 

 of inducing changes in that fluid similar to those which he had 

 previously regarded as only to be brought about by living organ- 

 isms. M. Pasteur, it is true, endeavoured to save the integrity 

 of his already modified germ theory, on the ground that this not- 

 living ferment is one which is called into being only by the previous 

 activity of vital ferments — since, as he maintains, it is as a result 

 of their ordinary life-processes that it is formed in the medium 

 in which they exist. 



Certain questions of much interest, to which it is important 

 here to call attention, have arisen in connexion with each of M. 

 Pasteur's extensions of doctrine. 



In regard to the extension of 1872, it may be asked whether 

 in all cases the fermentations initiated by the chemical changes 

 taking place in fruits placed under unhealthy conditions (as in an 

 atmosphere of carbonic acid gas) are always unaccompanied by the 

 appearance and development of ordinary ferment-organisms. And 

 in reply, it must be said that the researches of Lechartier and Bel- 

 lamy have shown that Bacteria constantly make their appearance 

 when experiments of this kind are made either with the beetroot 

 or the potato. This is declared to be an event of invariable 

 occurrence ; and the fact seems to be admitted by M. Pasteur, 

 though, on the other hand, he denies the statements of MM. 

 Premy § and Trecul to the effect that organisms are also habitu- 

 ally developed within the cells of many fruits in which the so- 

 called " intracellular " fermentation is taking place. 



But though he does not deny the occurrence of organisms, M. 

 Pasteur has not, so far as I am aware, made any good attempt 

 to account for their invariable appearance in the beetroot and the 



* Comptes Eendus, 1869, 1872, and 1874. 



t Ibid. vol. Ixxxiii. p. 5. | Ibid. Jan. 31, p. 333. 



§ ' Sur la Generation des Ferments,' 1875, pp. 179-191. 



