276 NATURE AND LIFE. 
attention of physiologists a year ago; the acetate of po- 
tassa, and others. Hitherto the physiological virtues of 
active principles have been studied only with respect to the 
higher order of animals: Dumas pointed out the great 
interest there would be in examining the influence they 
exert over the lower organisms charged with the elabora- 
tion of ferments, and over ferments themselves. Such re- 
searches not only contribute to a better knowledge of the 
mechanism itself according to which these principles affect 
the system of vital phenomena, but they also gain the most 
useful indications for the healing art. Indeed, beginning 
with the moment at which Dumas and other chemists 
made known the result of their examinations on this 
subject, coincident also in time with the experiments of 
Davaine on septicemia, a vast number of attempts were 
entered upon, in hospitals and in laboratories, to discover 
to what extent these anti-fermenting substances hinder mor- 
bid fermentations. These attempts are still proceeding; 
we cannot foretell their success, but we are authorized 
even now to say that they will not be barren of advantage 
to the healing art. In this, as in all other departments of 
scientific activity, we see abstract studies result in useful 
discoveries.’ 7 
As a general statement of the subject, all this immense 
work of fermentations, putrefactions, and corruptions of 
organic matter, is effected in the world by a small number 
of species of microscopic cells and filaments, by fungi and 
spores of the lowest order, of which the germs fill our 
atmosphere. This is one of the most certain acquisitions 
of modern science, one of the most important from the 
point of view of natural philosophy, one of the most pro- 
ductive for those arts that are concerned in improving the 
1 Since these lines were written, silicate of soda, experimented on by 
Rabuteau and myself, has taken a fixed place in the treatment of several 
purulent and putrid disorders. 
