ceeded in drawing simple conclusions from it in a concise manner 
and to formulate them sharply. In the formula 
the discussion of the term 7’. and of its first and second derivative 
function according to vw and y would already require extensive cal- 
culations, and the discussion of log Per and its derivatives would still 
augment the difficulties considerably. And though it is true, as we 
have observed above, that generally the influence of log p. is not 
: RT dT 
great, yet some cases occur, namely those, in which Fag and En 
are small, in which this influence is decisive. Therefore for the 
present I will not enter into an accurate discussion, and only inves- 
tigate some peculiar cases. 
So as first case we may suppose that the three components have 
been chosen in such a way, that the course of p will be represented 
by a straight line for each of the three pairs, which may be formed 
from the components of the ternary system. This may be the case if 
the difference of the critical temperatures of the components of these 
pairs is considerable and the critical pressures either differ but slightly 
or have such values that the expression : 
AT cy dper 
| Tdx Der dat 
may be considered to be constant for each of the three pairs. Then 
we may expect that for the ternary system u and w,, will be 
everywhere constant or nearly constant, from which follows that 
du’ and dw',, may be neglected compared with ws, and w,,. If we 
in fact neglect the values of du and du, the differential equation 
of the curves of equal pressure assumes the following form: 
0 = dlog {1 +a, (ei) fy, eh = 1}. 
And we get for the equation of the projection of these curves: 
C=1+a,e""—1)+y,("%—)). 
And we find for the value of p from equation (7) 
Po 
1 Wy pea 
La, (SI) + y, CPI 
The supposition namely that du’, and du’, are zero comes to the 
p=MRTe 
