The following are the results presented by our four series of comparative experiments in the different cases. The first ten flasks—our standard flasks, containing must boiled in contact with pure air—showed no signs of organized products; the must might have remained in them for any number of years without change. Our second series of flasks, which contained the water in which the grapes, separately and in bunch, had been washed, had undergone alcoholic fermentation in every instance; this had manifested itself in all the flasks in the course of about forty-eight hours, the temperature being at about summer heat. At the same time that the yeast made its appearance in the form of little white lines, which gradually joining together formed a deposit on the sides of the flask, we perceived minute flakes of _mycelium_ forming; sometimes as a single fungoid growth, sometimes combined with another, or with many together—these growths being quite independent otherwise of the yeast or alcoholic ferment. In several cases, too, _mycoderma vini_ showed itself on the surface of the liquid in the course of a few days. _Vibrios_ and lactic ferments, properly so called, could not make their appearance, on account of the nature of the liquid. The flasks of our third series, containing the water in which the bunch of grapes had been washed, and which we boiled before our experiment, remained as free from change as the flasks of our first series had done. Lastly, our fourth series of flasks, containing the drops of juice taken from inside the grapes, remained equally free from change, although we could not be certain of having removed, in every case, without exception, all causes of error which must inevitably occur sometimes in so delicate an experiment. These experiments cannot leave the least doubt on our minds: That must, if boiled, will never ferment when in contact with air that has been freed from the germs which exist in it in a state of suspension. That must may be fermented, after boiling, by introducing into it a very small quantity of water, in which a bunch of grapes has been washed. That must will not ferment if we introduce into it some of this same water which has been boiled and afterwards cooled. That must will not ferment if we introduce into it a small quantity of the juice contained in a grape.[36] It follows, then, that the ferment which causes grapes to ferment in the vintage tub must come from the exterior, and not the interior of the grapes. Thus, the hypothesis of MM. Trécul and Fremy, according to which albuminous substances transform themselves into grains of yeast by the action of a peculiar vital force, is annihilated; _à fortiori_, there can no longer be a question concerning Liebig’s theory, on the transformation of albuminous substances into ferments, by a process of oxidation.