STUDIES ON FERMENTATlOISr. 311 



to d-etermiue accurately, before anything else, whether the 

 object of their study is animal or vegetable in its nature, 

 whether adult or otherwise. To neglect this is as serious an 

 omission for such students, as for chemists would be the neglect- 

 ing to determine whether it is nitrogen or hydrogen, urea or 

 stearine that has been extracted from a tissue, or which it is 

 whose combinations they are studying in this or that chemical 

 operation. Now, scarcely any one of those who study fermen- 

 tations, properly so called, and putrefactions, ever pay attention 



to the preceding data Among the observers to whom 



I allude even M. Pasteur is to be found, who, even in his 

 most recent communications, omits to state definitely what 

 is the nature of many of the ferments which he has studied, 

 with the exception, however, of those which belong to the 

 cryptogamic group called torulacece. Various passages in his 

 works seem to show that he considers the cryptogamic organ- 

 isms called bacteria, as well as those known as vibrios, as 

 belonging to the animal kingdom (see Bulletin de I'Academie 

 de Medecine, Paris, 1875, pp. 249, 251, especially 256, 266, 267, 

 289, and 290). These would be very different, at least physio- 

 logically, the former being aerobian, whilst the vibrios are 

 anaerobian, that is to say, requiring no air to enable them to 

 live, and being killed by oxygen, should it be dissolved in the 

 liquid to any considerable extent." 



We are unable to see the matter in the same light as our 

 learned colleague does; to our thinking, we should be labour- 

 ing under a great delusion were we to suppose " that it is quite 

 as serious an omission not to determine the animal or vegetable 

 nature of a ferment as it would be to confound nitrogen with 

 hydrogen, or urea with stearine." The importance of the 

 solutions of disputed questions often depends upon the point 

 of view from which these are regarded. As far as the result 

 of our labours is concerned, we devoted our attention to these 

 two questions exclusively : — 1. Is the ferment, in every fermen- 

 tation properly so called, an organized being ? 2. Can this 

 organized being live without air ? Now, what bearing can the 



