KESPIRATION 27 



given interval of time the number of particles that pass 

 through from one side equals the number that pass 

 through from the other. 



Independent Behavior of Gases. — Suppose (case 2) 

 two spaces of equal size, A and B, should be separated 



Fig. 13.— Case 1: Equilibrium. 



by a membrane, and suppose a gas X should be intro- 

 duced into A and a gas Y into B (Fig. 14). Each one 

 of these gases would act independently of the other. It 

 would act as if the other were not there, as in case 1, and 



Fig. 14.— Case 2: Two gases separated by a membrane. 



would establish its own equilibrium (Fig. 15). If the 

 two gases should be kept from forming an equilibrium 

 by some mechanism that would keep the pressure of X 

 always greater in A than in B and the pressure of Y 

 always greater in B than in A, the passage would simply 



