( ifi-^ ) 



T A IJ I. K 1. 



The p=f(,v^) curve is convex' from .?' = () to ,7; = 0,66. 



Tlie curve p=zf(a\) lias a very sinii)le course: it turns cver)'- 

 where its concave side to the .v-axis. 



From the course of tiie curves follows linall)', that the vapour is 

 always richer in admixture than the liquid, the greatest dilïerencc 

 between a\ and ,i'.^ amounting to about 0,33. 



These curves were now compared ^\ilh the diirereutial eciuations 

 derived by van dkr Waals : 



Jl '^^' — ■^— '^'1 

 p da\ ,r, (1— A-j' 



which the curve /?=ƒ(,/,), mu.st satisfy throughout its course, wiioii 

 the volume of tlie liquid may be neglected by the side of the vohime 

 of the vapour and when the vai)Our phase may be considered as 

 being rarefied, and : 



1 dp x^—x, 



p d.r^ .V, (1— '^'i) 



whicii must iiold chieliy for the borders of the curve y> =/'(.*•,) under 

 the same conditions. 



From the tigiire n and -^ have been toiiiid for the vabies 



of .!■ indicated in Table II, then ,r,—^\ is derived from (lie ecpiatiou 

 and from this ,i\ and these values are compared with the obser\cd 

 values : 



