AND ITS BEARINGS ON PATHOLOGY 379 
much larger number of other sugary particles into alcohol and carbonic acid, 
it would seem necessary to assume further that the decomposition of some 
atoms of glucose into glycerine and succinic acid, under the deoxidizing agency 
of the torula, exercises a disturbing influence upon neighbouring particles and 
leads to their becoming broken up into simpler compounds without loss of 
atoms. Such a theory of the alcoholic fermentation of sugar would be a com- 
bination of the views of Pasteur and of Liebig; and while assigning with the 
former authority the primary and essential place to the growing organism, 
would admit with the latter a catalytic influence exerted by decomposing organic 
substances upon unstable compounds in their vicinity. And if this be the true 
state of the case, it will be seen that the glycerine and succinic acid, though 
produced in comparatively small quantity, so far from being secondary and 
unimportant, are in fact the primary effect of the action of the torula upon 
the sugar, of which the formation of alcohol and carbonic acid is a secondary, 
though simultaneous, result. And it is considerations such as these which seem 
to me to invest with special interest the occurrence of the odoriferous ethereal 
product above referred to as an accompaniment of the pure lactic fermentation. 
This theory of the alcoholic fermentation has the advantage that its prin- 
ciple is applicable not only to cases in which the organisms concerned thrive, 
like the Torula Cerevisiae, in the presence of free oxygen, and may be therefore 
supposed to be ready to take that element from fermentable materials when they 
cannot get it in the free condition,’ but also to fermentations like the butyric, 
where, as M. Pasteur himself has shown, the long and actively moving bacteria 
which appear to constitute the ferment, instead of thriving in free oxygen, are 
rendered incapable of development by it, if not deprived of vitality altogether.? 
There seems no reason for supposing that an organism upon which oxygen in 
the uncombined condition operates as a poison, should be specially disposed to 
abstract that element from its combinations. We have in fact, here, the con- 
verse of the conditions of the Torula Cerevisiae. But nothing is more natural 
than that such a bacterium, when growing at the expense of an organic material, 
should take for the purposes of its nutrition some of the atoms composing that 
substance and leave the rest to form new combinations ; and the decomposi- 
tions arising in this manner may operate with catalytic effect upon neighbouring 
* Another well-known instance of this is presented by the common mould, Mucor vacemosus, which, 
when growing at the surface of a saccharine solution, produces little or no alcoholic fermentation, but 
brings about that change in very considerable amount when compelled to grow below the surface where 
but little free oxygen is at its disposal. M. Pasteur has also demonstrated that even Penicillium glaucum 
and Aspergillus glaucus have the same effect, though in a much more limited degree, when placed in 
similar circumstances. (Vide “tudes sur la Biére.) 
* To use M. Pasteur’s own words, the atmosphere acts upon them with ‘influence mortel/e’; the 
italics are the author’s (/:tudes sur la Biére, p. 293). 
