70 MICROBES, FERMENTS, AND MOULDS. 
tion in putrefying bodies which would not be rejected 
by modern naturalists and chemists. 
“After death .. . the foreign ferments, which are 
always intent on change, are borne through the air 
and introduce corruption into dead matter... at 
least, unless the flesh is combined with certain sub- 
stances, such as sugar, honey, or salt, It is, therefore, 
these ferments, attacking whatever matter is deprived 
of life, which disintegrate and prepare it to receive a 
new soul (or fresh life).” 
Linnzus, again, says that “a certain number of 
diseases result from animated, invisible particles, which 
are dispersed through the air... .” Boerhave, in 1693, 
distinguished three kinds of fermentation: alcoholic, 
acetous, and putrefactive. But we must come down 
to the beginning of this century in order to find more 
definite ideas respecting the organic nature of ferments. 
In 1813, a chemist called Astier asserted that 
every kind of germ from which ferments proceed is 
carried by the air; that this ferment, of animal 
nature, is alive, and is nourished at the expense of 
the sugar, and hence results disturbance of the 
equilibrium between the elements of sugar. 
Subsequently, in 1837, Cagnard de La Tour de- 
clared yeast to be a collection of globules which are 
multiplied by budding; and in the following year 
Turpin described the yeast of beer as a vegetable, 
microscopic organism, which he termed Torula cere- 
visi (Fig. 35). 
