580 



Adeney — Dissolved Gases and Fermentative Changes. 



those which are recorded for the preceding experiment 4, to allow us, I think, to 

 regard them as indicating the volume of oxygen absorbed, and of carbon dioxide 

 formed during the conclusion of the first-stage fermentation, without introducing 

 serious errors. 



If this assumption be allowed, we can sum together the volumes of carbon 

 dioxide formed, and of oxygen absorbed, during each of the steps of the first-stage 

 fermentation represented by experiments 1, 2, 3, 4, and 5, and obtain the total 

 volume of carbon dioxide formed, and of oxygen absorbed, by the complete first- 

 stage fermentation of the two organic substances originally present in solution A. 

 Thus :— 



The total volumes of carbon dioxide formed, and of oxygen absorbed, at the 

 conclusion of the first-stage fermentation, we then see are 75-01 and 49-49 cos., 

 respectively. The ratio of these numbers to one another is as 1-52 ; 1, which 

 approximates to the volumes of carbon dioxide and oxygen, which, as I stated 

 above, would be respectively formed and absorbed, were the two substances 

 present in solution A directly oxidised completely to the ultimate inorganic 

 products, carbon dioxide, water, and ammonia, viz. 1*465 : 1. 



It appears then, from this, that notwithstanding the fermentative changes 

 which were set up in solution A other than those which would result from simple 

 oxidation during the earlier steps of the first-stage fermentation, the total volume 

 of carbon dioxide formed, and of oxygen absorbed, resulting from the complete 

 first-stage fermentation of the two substances present in the solution, bear ap- 

 proximately the same proportion to one another as if the fermentation had con- 

 sisted throughout of a simple and direct oxidation by the oxygen absorbed acting 

 upon an equivalent quantity of the mixture of the two substances originally 

 present in the solution. 



On turning to the results of the experiments with the dilute solutions of A, 

 recorded in Table VIII., we observe that dilution seems to exert a very decided 



