STUDIES ON FERMENTATION. 371 



that time, nor were tliere even any buds then visible on them. 

 The oxygen, therefore, must be stored up somehow in the cells, 

 taken up by their oxidizable matters to be brought into work 

 subsequently, or to act as a. primum movensoi life and nutrition, 

 spreading its influence over several successive generations of cells. 



§ IV. — On the Combination of Oxygen with Wort. 



The atmospheric oxygen is not merely taken into solution by 

 wort ; it also combines with it, as a very simple experiment will 

 suffice to show. If we place in a tinned iron vessel some boiling 

 wort, separated from the hops in the copper, and cool it sud- 

 denly by plunging it into iced water, and after having cooled 

 it down in this manner to 15° or 20° C. (59° or 68° F.), saturate 

 it with oxygen, by shaking it briskly in a large flask, and then 

 completely fill a vessel with it and close it up for twelve hours, 

 we shall find at the end of that time, if we test it with the 

 hydrosulphite of soda, as we have described in § II., that it 

 does not contain a trace of free oxygen. The whole of the gas 

 which was originally held in solution will have entered into 

 combination, that is to say, the liquid, first coloured blue with 

 the indigo-carmine, and then brought to a yellow tint by means 

 of the hydrosulphite of soda, will not regain its original blue 

 colour through the action of this wort. The following experiments 

 were undertaken with the object of studying this property of 

 wort, and in order that we might form some idea of its import- 

 ance, and of the total quantity of oxygen that wort can absorb 

 under certain special circumstances. The experiments were 

 performed in our own laboratory on wort from Tourtel's 

 brewery, which M. Calmettes had forwarded to us in bottles 

 prepared in the brewery at Tantonville, in the following man- 

 ner : Each bottle was filled with boiling wort taken from the 

 copper and closed with a bored cork, through which the neck 

 of a funnel passed ; the funnel also was filled with the wort, and 

 the whole preserved from contact with air by a layer of oil. The 

 next day the bottles were corked full by the help of a bottling 



B B 2 



