20 



RESPIRATION 



lated so as to give a constant percentage of CO2 and not of oxy- 

 gen. The following results were obtained with oxygen percentages 

 varied at intervals in the same subject. 



This table shows that increase in the oxygen percentage over 

 short periods had no noticeable influence on the alveolar CO2 

 percentage, and that not until the oxygen percentage in the in- 



