FOUNDATIONS OF THE KINETIC THEORY OF GASES. 275 



/ 



. m Mi) jmm <«(*) jogKg. «({)| 



>)-16f(|) F W -4 F (f) (|F W -16F(f)) ! " 9F t"» (F W -4F(|)y * F « 



The corresponding- curve is exhibited by the dashed line in the sketch, and its 

 area is about —3 '157. Hence, in this case, 



1 I' = - -TTT 3 " 793 • 



F!bi mm ^h ■»■ ^fi nai 



(c) Still keeping the sum of the semidiameters the same, let the diameter of 

 a P 2 be three times that of a P r The integral is 



r 



dy 

 o 



Ay) 



U/(i) \^V)m , 6«\f) 576F(|V(f), 36F(f)1 



4- lOfT — - - - I lop 2 L 



+ T-1 r9 l0 g xv\ --, " , l0 S" 



1^)-16F(-|-) F„)-36F(|) (^F(,)-16F(f ))' ^ (F<y)-36F(f )) 



?(y) 



The curve is the dotted line in the cut, and its area is about — 1*7 13. Hence 

 we have 



/*!i ] 1 3.312 



dt TTH" ^'/t^ 



If we compare these values, obtained on such widely different assumptions as 

 to the relative diameters of the particles, we see at once how exceedingly 

 difficult would be the determination of diameters from observed results as to 

 diffusion. (Compare § 54.) 



VOL. XXXIIT. PART II. 2 R 



