( 153 ) 



Fig. 32. 



volume, and where it proceeds again to greater volumes. On the 

 supposition that a M 3 might rise above a x a t , fig. 1 would not repre- 

 sent all possible cases of the course of the isobars with respect to 



/dp\ 



{ — ■ J = 0. But I observed alreadv on page 630 in what way tig. 1 would 



\dccj v 



have to be extended if other suppositions on a l -{-a 3 — 2a ls are 



admitted e. g. a l -\- a t — 2a la == or a l -f- a t — 2a l3 negative, and 



the supposition a l a 3 <[ a s M lies in this direction. 



If we continue increasing a x „ not onl} r above \/a x a„ but even 



k a i + a s .1 

 above , then m = 



\d.vj 



is negative, and - lies between 2 

 d'a b 



dx* 



fdp\ /dp\ 



and 3 for the point of contact of — = and — 1=0, and 



\dxj \dvj x 



so 



dvj x 



this point of contact always lies on the liquid branch of 



We might also have arrived at the above results by another course, 

 which would give us an opportunity of making some new remarks. 

 For if we think the quantity v eliminated from the two equations 



