608 



Experiments 



indicate the absolute quantity of the gases which have disappeared. 

 Columns 14 and 15, more instructive, express the proportion which 

 has disappeared and not the absolute quantity. They were ob- 

 tained by operations like the following: 



Experiment No. 1 — 



O2 . . 21.6 (col. 3) : 3.0 (col. 12) = 100 : x = 13.8 (col. 14) 



CO . . 36.3 (col. 4) : 0.9 (col. 13) = 100 : x = 2.5 (col. 15) 



Examining first Column 8, we see that the quantity of oxygen 



IS 



Fig. 31 — Decrease in amount of O and CO 2 in the arterial blood, when 

 the barometric pressure is diminished. 



