
IMPORTANT NEW EXPERIMENTS 133 
changes leading to fermentation, as originally sug- 
gested by Gerhardt—and among these changes a 
process of life-origination. 
This important question would seem to be so 
capable of being settled by crucial experimentation 
as to make it not a little remarkable that no such 
attempt was ever made by M. Pasteur. Thus, the 
fluids may be boiled in their acid state so as to kill 
all their contained germs and organisms, and to 
these fluids boiled liquor potassee may be added 
in suitable quantity.1. The results of a number of 
such experiments should be sufficiently decisive to 
enable us to fix upon the true mode in which liquor 
potassee operates in determining fermentation. If 
the fluids to which boiled potash is added in suitable 
quantity still remain barren, then such experimental 
results would unquestionably favour the first inter- 
pretation, viz., that given by M. Pasteur and adopted 
by other germ-theorists. If, on the other hand, the 
addition of the boiled liquor potassz, to the urine 
which has been boiled in its acid state, suffices 
to convert this previously pure fluid into a turbid 
liquid teeming with ferment-organisms, then it would 
be conclusively shown that the increased ferment- 
ability of neutralised urine was ascribable to the 
second cause, viz., to the chemical influence of the 
liquor potassee in initiating fermentative changes, 
whatever the precise nature of these early changes 
may be. 
1A few experiments of this nature were first made by William 
Roberts with hay-infusion (“ Phil. Trans.,” 1874, vol. clxiv. pt. 2, 
Pp. 474). 
