10 FroceecUngs of the Royal Irish Academy. 



TJie Organisms effecting the I er mentations. 



In most of the experiments to be described, care has been taken 

 to avoid commencing with organisms in a state of activity, because 

 their enzymic action would mask the respiratory changes which it was 

 also desired to study. 



Consequently the germs present in the distilled water, and other 

 substances employed in making up the solutions, have been relied upon 

 for setting up fermentation. 



In the course of three months or so, the solutions become slightly 

 turbid ; and the turbidity becomes more distinct a few days later, and 

 remains until the fermentation is complete. 



Table I. 



Analyses giving the oxygen consumed, and the products formed, by 

 the respiratory and enzymic changes exerted by the organisms 

 during the earliest stages of their development and activity in 

 solutions of urea. 



The gases are stated in c.c. at ^N", T. P., and the organic nitrogen and 

 inorganic nitrogen compounds in gi-ms., per litre : — 



Dissolved Gases. 



Nitrogen- as 



No. 



CO2 



Oo 





Organic 



NH3 



N2O3 



1 



19-63 



6-99 



13-74 



0-105 



0-0001 



0-0 



2 



20-53 



6-42 



lS-o6 



0-105 



0-0003 



trace 



8 



23-19 



3-05 



13-50 





0-0032 



0-00148 



4 



29-88 



0-01 



13-47 1 





0-0108 



0-00247 



5 



42-22 



0-00 



13-40 



1 



0-077 



0-026 



0-00244 



