Mi THOD FOR Mil RMINING Rl 5PIRATORY l K( ll M 



l>> I I: Q. — 



in :iiin aii 



CO,ii pircd air Id 



100 20.9-1 : 79.06%, \ in atmo 

 LOO 20.50 : l N in expired i 



Since the nitrogen is not changed in volume, the last figure Bhov 

 more oxygen musl have been taken in durii a piration than CO 

 has been given back in expiration. This obviously must be taken into 

 accounl in the calculations. The amounl of O actually inspired 

 LOO c c. of air expired is found as follov 



20.94 (% 0, in atmos pln-i i<- : 

 79M (% N 2 in atmospheric :<i, 

 stant factor 7:'.:, • . \ foui d foi this observation 21. 

 would have been present in expired di I ml for N present. 1 



21.07 L6.50 l.57< 1 1 actually absorbed. 

 '■' .03 C< i ii. inspirt d air 3.97< 



3.97 

 :. -£-z== 0.87, the respiratory quotient, 



Total Gas E change. The volume of air expired in 15 minutes 

 tli«« Tissol spirometer was found to be LOO Utera measured at 20 C. and 

 717 mm. Mir (brass-scale barometer). This volume of gas musl 



rected so as to give the volun E dry air at o ami Ttio nun. Bg. '1*.. .1" 



this two things must be taken into account. 1 since the expired air is 

 saturated with water, the pressure dm' t" water vapor musl be subtract 

 from the observed barometric pressure to obtain the true pressure. I 

 vapor tension of water for various temperatu given in Table 11 



"ii page 564. (2) The barometer tube lengthens or contracts with i 

 or cold, and therefore the barometric readings must \x 

 The corrections for ordinary barometric reading found in Table IN. 



page 565. The figure corresponding to the temperature* s subl 

 from the barometric reading in order to obtain correcl barometric p 

 sure. 



In the above experiment, the correction for the b ; 1 mm. 



Table III. pag . and that for vapor tension al 20 I i 17.4 



Bee Table II. p t 



Actual Barometrii /' i 747 17.5 2 727.21 mm. 



coefficient of expansion of is taken as 



the volume of equals the volume at 1 divided by 1 

 hence 



" T I 

 tThis 

 {ponding t" the i ' • 



