On Expressed Yeast-cell Plasma (Buchncr's " Zymase "). 255 



placement of salt solution. The volume of gas evolved is expressed 

 in this and the following tables on 100 c.c. of juice, although the 

 quantity actually used was, as a rule, either 25 to 40 c.c. 



It will he noticed that in nearly every instance more gas was 

 obtained from the auto-fermentation of the juice than from the 

 fermentation in the presence of cane-sugar. This was usually the 

 case with the juice from the yeasts of A, C, and D breweries ; how 

 far it is due to the distinctive character of the yeasts or to the high 

 sugar concentration we are at present not prepared to say. Another 

 point to be noted is the great variation in the activity of the juice 

 from different samples of yeast. We noticed this throughout the 

 whole of our experiments, but we are unable to correlate it with any 

 of the physical properties of the juice, such as gravity, &c. It will 

 also be seen that by far the greater part of the action is at an end 

 after twenty-four hours, there being either no further increase in the 

 amount of gas evolved, or comparatively little. This we also found 

 common to the majority of our experiments, as will be seen from 

 subsequent tables. 



Table I. Volume of Carbon Dioxide evolved by Cell Juice from 

 different Yeasts, with and without the addition of Cane-sugar. 



* Toluol used as antiseptic. t Sodium arsenite used as antiseptic. 



In this experiment 10 per cent, cane-sugar was employed. 



