( 606 ) 
if we neglect the second powers, from which follows for the two 
roots : 
Gie OF: Cia Cm 
i {eo oe eee 
v 2 7) En 2 
db \? 
: 2MRT| — 
2C, dx Co gfe 
va =e Ir =—b 
C, da 2 
dx’ 
So we have one finite root and one root equal to zero from which 
: : 1 
follows fig. 4 for the course of = ==); 
a“ 
Fig. 4. 
5. In the second place we have to examine the course of 
d, : 5 
= in the ease now under consideration. We may write the 
2] 
equation of this curve in the form: 
MRT v? — 2a(v—b)? = 0. 
It is very easy to separate the roots of this equation. For, when 
a is positive, the first member is negative for v — 0, positive for 
vb, and positive for y=. So there is a root between O and 
bh, and either two or none for v > 6, as is known, according as the 
critical temperature is below or above the critical temperature for 
the mixture under consideration. When 6 becomes equal to 0, both the 
product of the three roots and the sum of the products taken by 
twos becomes equal to zero. So there are two roots v =O in this 
2a 
case. And the third root assuming the value UR’ the two branches 
