puscles of the blood, which are also charged with trans-
porting oxygen to the tissues, giving it up to certain sub-
stances in preference to others, thus carrying on the
oxidation that is needed, even if it is not voluntary and
premeditated. He had asked himself what would hap-
pen if the red corpuscles should become diseased in the
same way as the cells of the acetic ferment, arrested in
their development in the aldehyde stage of oxidation.
In short, he penetrated through his micro-organisms, into
the laws of physiology and pathology.

The practical consequences of his discoveries equalled
their theoretical promise. They restored security to
the Orléans vinegar manufacturers, who were hence-
forth masters of the mycoderma veil in their casks
instead of being subject to its demands and caprices;
they made it possible for the boldest of these men to
adopt a new method of manufacture whereby, instead of
leaving intact for a long period the pellicle formed on
the surface of the liquid, they resowed it and renewed
it at frequent intervals. Thus not only could one make
more rapid progress, but could regulate the production
to the demand, whereas, by the old Orléans method
production must be going on constantly and the casks
could not lie idle, lest they should become inert.

But is it only in the Orléans process that the microbe
intervenes? Not at all. We find it also in the German
process, but it is less apparent there, because it is formed
in much less quantity. In Orléans, the white wines,
rich in organic matter, are used especially for vinegar-
making, and the layer which develops on the surface of
the liquid in the casks forms thereon sometimes a thick
veil. In Germany, little else is used for vinegar-making
except alcohols diluted with water and mixed with that
small quantity of wine, or sour beer, which Liebig
demanded. This liquid is not very nourishing and seems

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