I>r. A. Macia.lym, I)r. (>. H. Morris, ;iml Mr. S. l!.i\vlaml. 



between the residual alcohol and the carbon dioxide is very variable, 

 an<l only in cases in which ;i very active juice is employed does the ratio 

 approximate to that found by Pasteur.* With a weak juice there appears 

 to be little or no connection between the two, the amount of alcohol 

 formed being, as a rule, greater than the carbon dioxide. The small 

 quantities of alcohol to be determined may be thought to be account- 

 a le for the discrepancy between the two products, but the following 

 pie of a determination carried out in duplicate shows that our 

 methcds were capable of considerable accuracy. 



I. II. 



Gramme. Gramme. 



Carbon dioxide evolved 0-327 0*337 



Alcohol formed 0'95 0'95 



Sugar fermented M67 M58 



One very remarkable fact comes out in all the above experiments, 

 namely, that the amount of sugar which disappears is greatly in 

 of that actually fermented, as deduced either from the alcohol or from 

 the carbon dioxide formed. The closer the relationship, however, 

 between the two products, the less is the excess of sugar which dis- 

 appears. 



It occurred to us that there might be some constituent of the juice 

 which interfered with the correct determination of the sugar, but we 

 put this to the test and found that when we added sugar to the juice, 

 and then killed its action by heat before any fermentation could take 

 place, the whole of the sugar could be accounted for by Pavy's method 

 of determination. 



We also submitted the residual product after fermentation had 

 taken place to hydrolysis with very dilute acid with a view to break 

 up any hydrolysible compound which might have been formed between 

 the constituents of the juice and the excess sugar which had disap- 

 peared, but without any result : the reducing power before and after 

 treatment remained the same. The sugar had therefore apparently 

 disappeared as such, and had not simply been rendered unrecognisable 

 to ordinary tests. 



We are at present only able to chronicle this most interesting fact, 

 as at the present stage of our work it would be premature to make 

 any theoretical deductions ; but in connection with this remarkable 

 disappearance, we venture to throw out the following suggestion : 

 During the life of the yeast, sugar is consumed by the organism with 

 the resulting production of carbon dioxide and alcohol. Considered 

 in detail, this process probably occurs in two stages (1) a building up 

 and incorporation of the sugar molecules into the actively living proto- 



* Cane-sugar yields 51'11 per cent, of alcohol and 49'42 per cent. COj. 

 Dextnr l^-oo "> 



