( 809 ) 
da db k 
when the temperature at which ae MRT ER for «= &,, is reached. 
at at 
Our diagram then passes into the usual one, when this is drawn 
above the critical temperature, and as we have now to deal with 
the case of fig. 9, into the usual figure after the intersection of 
X 
EE 
\ * 
+. 
¥ Seah CR f 
~ : +2 Arn 
* 
V 
Fig. 14, 
d d 
B — and =0 has disappeared. 
dv da 
16. Now the course of the isobars for the case that a minimum 
critical temperature occurs at the same time with a,,* >a,a, is 
completely determined. Only this complication might possibly be 
met with — I have at least not succeeded in proving that it is 
d, 
impossible — that besides the discussed contact of ee O and 
) 
dp 
3 = 0, by which two points of intersection arise, another contact 
av 
is found. As we saw before the points of contact which then arise 
will again have to move to opposite sides. Of the four points of 
intersection which there are in this case, the two inner ones will 
again coincide at still higher themperature, and give rise to contact. So 
the difference is confined to the region between the two temperatures 
of contact, and it has only influence on part of the isobars at 
small volumes. Thus of the series of isobars which pass round the 
; ae dp ! 
point with minimum pressure on isa 0 as closed curves, there will 
av 
