232 ALCOHOL, VINEGAR, SAUER KRAUT, TOBACCO, SILAGE, FLAX. 
experimental jars in which chloroform vapor prevents the growth of 
bacteria, although it allows the enzyme action to continue as usual. 
It goes through a fermentation that is fairly typical, a fact that shows 
that the essential phenomena of ensiling may be wholly the result of 
these two sets of activities. 
The Action of Microorganisms. It was first thought that the 
fermentation of silage was a bacterial action wholly, but further 
study showed the fallacy of this conception. The original fer- 
mentation, by which there is a rapid rise in temperature, cannot 
be the result of bacterial growth, since it is too rapid and the 
temperature rises too high. There is no evidence to suggest that 
any bacteria can produce a rise as high as 150, a temperature that 
destroys the life of most organisms. If the rise were due to bacteria 
it would be rather slow, rising only as the bacteria had the oppor- 
tunity to develop, while on the contrary it is very rapid. Finally 
the possibility of making silage in a jar filled with chloroform vapor 
shows that bacteria are not necessary for the phenomenon. 
But this does not by any means exclude the agency of micro- 
organisms in the ordinary formation of silage. Bacteria are cer- 
tainly present and, in some cases, they are present in great numbers. 
Some bacteriologists have not been able to find them so very abun- 
dantly, but this seems to be due to the fact that they did not use 
favorable media in studying them, for when a medium is used 
that is adapted to the silage bacteria, they are found in abundance. 
Certainly, if they are present and develop during the fermentation, 
they must have some effect upon the silage. One effect they cer- 
tainly seem to have. The silage turns acid during the ensiling, and 
this acidity appears here, as in other cases which we have noticed, to be 
a means of preventing subsequent putrefactive changes. Without 
doubt this acidity may be attributed in part, if not wholly, to acid- 
forming bacteria growing in the silo. 
Further, there develop in the silage certain prominent flavors 
which contribute largely to its value, and the source of these flavors 
is as yet unknown. Aromatic flavors such as are found in silage do 
not come from respiratory processes, nor do enzymes develop such 
flavors, so far as is known. There are some who think, however, 
