20 August Krogh and Marie Krogh. 



The calculation of the respiratory exchange is complicated by 

 the fact that the quantity of air entering the chamber from outside 

 A is not identical with the quantity found as outgoing, because the 

 volume of CO2 produced is generally different from the volume of 

 O2 consumed. As however the quantity of nitrogen is not affected 

 by the respiratory processes it becomes possible to calculate the volume 

 of outside air which must have entered in order to make up the quan- 

 tity present. 



We have therefore: 



Axn^ = Bnß-\- Drij) — Cn^ 



Па Па Па 



The quantity of CO^ produced during a period must be the diffe- 

 rence between the quantities in the outgoing and ingoing air as ex- 

 pressed by: Be,- Ac, + Dc,- С c, 



or when the above value for A is put in: 



В 



{с.-с/;увс^+сс,+ф1-с1). 



As however c^ is always very small (about 0.03) and practically 

 constant and as the factor ^ and the analogous can vary only be- 

 tween 0.9994 and 1.003 we may with quite sufficient accuracy put 

 the CO 2 as equal to: 



В [Cß — c2) + D Cjj —CCf,. 



The quantity of oxygen consumed is expressed by: 

 Aoj^ — Boß+ C0(^, — Do J) 



=^(ï— ^)+m::?^-m-^(:;?''-'")- 



The expression ^0^ — o, and the analogous are transformed by ad- 

 dition and subtraction of Oj^ to: 



Oa — Oß-\~ Oj^i -^ — 1 j and the analogous. 



A small table has been worked out showing the values of the 

 last term corresponding to the different values which n,, Uq and rij) 

 may assume and we have therefore the amount of oxygen consumed as: 



В (о A — Ob-\- corr.i) + i) к — Oj) + СОГГ.2) — с (0^ — Oe + cocr.3) 

 where the corrections are put in from the table. 



