those of
Mycoderma vini, etc. This being done, ten of the forty flasks were
preserved for reference; in ten of the remainder, through the straight
tube attached to each, some drops of the washing-water were introduced;
in a third series of ten flasks a few drops of the same liquid were
placed after it had been boiled; and, finally, in the ten remaining
flasks were placed some drops of grape-juice taken from the inside of a
perfect fruit. In order to carry out this experiment, the straight tube
of each flask was drawn out into a fine and firm point in the lamp, and
then curved. This fine and closed point was filed round near the end and
inserted into the grape while resting upon some hard substance. When
the point was felt to touch the support of the grape it was by a slight
pressure broken off at the point file mark. Then, if care had been taken
to create a slight vacuum in the flask, a drop of the juice of the grape
got into it, the filed point was withdrawn, and the aperture immediately
closed in the alcohol lamp. This decreased pressure of the atmosphere in
the flask was obtained by the following means: After warming the sides
of the flask either in the hands or in the lamp-flame, thus causing a
small quantity of air to be driven out of the end of the curved neck,
this end was closed in the lamp. After the flask was cooled, there was
a tendency to suck in the drop of grape-juice in the manner just
described.
"The drop of grape-juice which enters into the flask by this suction
ordinarily remains in the curved part of the tube, so that to mix it
with the must it was necessary to incline the flask so as to bring
the must into contact with the juice and then replace the flask in its
normal position. The four series of comparative experiments produced the
following results:
"The first ten flasks containing the grape-must boiled in pure air did
not show the production of any organism. The grape-must could possibly
remain in them for an indefinite number of years. Those in the second
series, containing the water in which the grapes had been washed
separately and together, showed without exception an alcoholic
fermentation which in several cases began to appear at the end of
forty-eight hours when the experiment took place at ordinary summer
temperature. At the same time that the yeast appeared, in the form of
white traces, which little by little united themselves in the form of a
deposit on the sides of all the flasks,
|