16 



Proceedings of the Royal Irish Academy. 



Table Y. 



Analyses giving the total atmospheric 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 and Rochelle salt. 



No. 



Date. 



Dissolved Gases. 



Nitrogen 



AS 







CO2C.C. 



O2 c.c. 



N2 c.c. 



NH3 grs. 



10 



At commencement, . . 



19-60 



5-34 



11-25 



0-0002 



11 



Six days later, .... 



32-04 



0-19 



10-69 



0-0003 



12 



Nine days later, . . . 



32-65 



0-00 



10-79 



0-0007 



13 



Twelve months later, . . 



33-38 



0-00 



11-05 



0-0009 



14 



Seven days later, . . . 



Atmosphere of flask in 

 No. 14— 



70-25 



4-74 



13-31 



0-0220 





At commencement, . 



0-00 



160-84 



606-34 







At conclusion. 



0-00 



138-09 



601-88 





Prom the results recorded in the above Table, it will be noticed 

 that one of the most marked influences of the Eochelle salt is to set 

 up a very rapid fermentation. It will also be noticed that in No. 11, 

 although nearly all of the oxygen had been consumed, only a minute 

 quantity of ammonia had been formed. After three days' longer 

 fermentation in another portion of the solution, No. 12, a small 

 quantity was formed ; but this seems to have been the limit for the 

 stage of development which the very small quantity of dissolved 

 oxygen originally present allowed ; since, when a third portion of the 

 solution (11) was kept for nearly eleven months, the amount of 

 ammonia found in it was but little more than that in No. 12. 



But when a larger supply of atmospheric oxygen was provided, 

 as in experiment 14, more advanced stages of fermentation very rapidly 

 set in ; and in seven days from the commencement of the experiment 

 about one-fifth of the urea originally present had been hydrolysed into 

 ammonium carbonate. 



