88 



Mr. E. C. Grey. Decomposition of 



It is of interest to add together the aoetic acid and succinic acid produced 

 in each experiment. It will be seen that, in each case, the combined weight 

 does not differ very greatly from 33 per cent. The same applies to the sum 

 of the weight of acetic acid and alcohol. When the fermentation has taken 

 place under certain conditions, as in Experiment 3, the sum of either of 

 these two pairs of products no longer approximates to a constant figure, but 

 the point to which the writer would draw attention is that, throughout 

 conditions which have varied sufficiently to introduce considerable variation 

 in the individual products, the sum of these pairs approaches very closely to 

 a constant. Thus, a variation, as seen between Experiments 4 and 5. 

 represents nearly 100 per cent, on the amount of succinic acid, and yet only 

 about 5 per cent, on the sum of succinic acid and acetic acid. Similarly, the 

 alcohol, as between Experiments 4 and 5, has varied by 100 per cent., but 

 the sum of alcohol and acetic acid has only varied by 4. 





4. 



5. 



6. 



7. 



8. 



10. 



11. 



Mean. 



Acetic acid 



15-6 

 19 -6 



23 -2 

 10 7 



16-0 

 18 -0 



18 -6 

 17 -4 



18-0 

 15-1 



22 -0 

 11 -2 



19 -9 

 9-8 







35 -2 



33 -9 



34 -0 



36 -0 



33-1 



33 -2 



29 -7 



33 -6 



Acetic acid 



15 -6 



16 -e 



23 -2 

 8-3 



16 -0 

 15 -6 



18-6 

 20-0 



18 -0 

 14 -3 



22 -0 

 13 -4 



19 -9 

 13-2 







Sum 



32 -2 



31 -5 



31 -0 



38 -6 



32 -3 i 35 -4 



1 



33 -1 



33 -4 





Doubtless, these regularities are in part due to some constancy in the 

 ■conditions which is not apparent, but, nevertheless, the results are highly 

 suggestive that succinic acid, which is, in point of fact, di-acetic acid, arises 

 in this fermentation from the same intermediate substance which gives rise 

 to acetic acid. And, again, since acetic acid is shown to be similarly related 

 to alcohol as regards its origin, it seems clear that the three substances arise 

 through the agency of the same enzyme or enzymes. These results suggest, 

 therefore, that succinic acid may arise by the union of two — CH2COOH groups. 



The close relationship of these three substances is pictorially represented 

 below. 



'-CH2-C(0H)0 



H- 

 H 



-CH2-C(0H)0 



H— CH2-C(0H)0 



