546 THE POPULAR SCIENCE MONTHLY, 



To conclude, fermentations occasioned in certain media, by the act 

 of development and nutrition of ascertained microscopic animal or 

 vegetable existences, present a group of well-defined characteristics. 

 They follow obediently all the variations that may occur in the physio- 

 logical activity of the microscopic beings contained in the liquid. 

 This does not go into fermentation all at once ; it delays more or less, 

 and molecular movement makes itself perceptible in it by degrees. 

 The phenomenon is one of evolvement. This appears to be the char- 

 acteristic of alcoholic, lactic, acetic, butyric, glyceric, and putrid fer- 

 mentations — all of those, in short, which M. Pasteur has studied with 

 so convincing accuracy. Is it the same with the conversion of amyla- 

 ceous substances into sugar, under the influence of diastase or ptya- 

 line, with the dissolving of proteic substances by pepsin, with the 

 change of amygdaline into the essence of bitter almonds, by contact 

 with synaptase ? Evidently not. These phenomena present another 

 aspect ; they show no stages of evolvement. Doubtless they require 

 a certain time for their completion ; but they take place all at once, 

 and without any relation to the surrounding air. 



These differences between the two kinds of fermentation clearly 

 depend on this : that, in the former, the phenomenon is subjected to 

 the conditions and vital progress of those organized corpuscles which 

 elaborate the ferment within the substance of the fermentable liquids, 

 while, in the latter, the phenomenon is brought about by a ferment 

 already formed and prepared. But this latter ferment is no less of 

 organic origin ; it, too, arises from living beings, animal or vegetable. 

 Whether it emanates, like diastase, from the young cells of the seed, 

 or results, like pepsin, from work done in the digestive apparatus, it is 

 the labor of life, just as much as if it had been completed by globules 

 of yeast or bundles of bacteria. Thus the efiicient sources of all fer- 

 mentations are the same. All ferments are at bottom alike, whether 

 procured directly for the fermentable liquid by microscopic bodies in- 

 habiting it, or emanating from corpuscles that inhabit elsewhere. The 

 true doctrine of fermentations consists in this point. 



Henceforth, then, we may consider ferments as products of a fecun- 

 dation taking place in cells, as secretions elaborated by those myriads 

 of infinitely little corpuscles, some crowded, squeezed, condensed, into 

 the palpable organs of animals and plants — others free and moving, 

 disseminated, as we shall see, into vast, intangible space. The energy 

 which distinguishes these microscopic animal and vegetable growths 

 also belongs to the microscopic elements making up the living tissues 

 in the higher animals. We must give to this property, hitherto con- 

 sidered as special, the high dignity of a fundamental and universal 

 attribute of organized cells. We must detect, in the most complex 

 conversions and processes of nutrition in superior beings, the same 

 untiring and primitive force that marks the subtile action of invisible 

 and insignificant monads. 



