( 126 ) 
and 
das di dike (1—y,) (e” *—1) Soin (ei ft 
4 ib a, iu —1) +Y, (es —1l) 
we have: EED 
eh —1 
i pared We 
Ne et 
This equation represents a right line, if the factor of #, is constant, 
and it yields «,—1 if y,=0. If the surface of saturation is a 
: “¢ fy Ps ey Ps 8 : 
plane, ie. if e * =— and e “4 =—, then the equation of this 
Pr Pr 
right line is: 
—— 
1—2#,=y, eT : 
Ps =P: 
This right line coincides with the liquid branch of the projection 
of the curve of the pressure p,. (See our previous Communication, 
p. 14). 
If wt, and w’,, are not constant, ie. if the factor of y, is variable, 
then the locus of the points for which zr, = 0 is of course not 
straight, but it will be a curve, which, however, if the condition 
wy, > u's, continues to be satisfied, will start from the same angle 
of the triangle. In this case the line for which «,—v,—=0O does no 
longer coincide with the line for which the pressure is equal to p,. 
If we put in equation (7) of p. 12. 
eN Eik 
u ’ 
e' Ei if, 
lr, = U. 
then we find: 
P 
MRT 
If we denote the value of u for r=1 and y=0 by u, then 
we have: 
log — Urn, = (1 —a,) Ws, sae Uy, —1. 
p | 
ee Urn + Aa) Un IH Bj Hor 
3 
The second member of this equation represents the distance between 
the point of intersection of the tangential plane to the g-surface and 
the vertical axis of the second component, and between the ordinate 
Ho If the whole surface lies below the tangential plane, as is 
probable, then the second member is positive and p > p,, and the 
difference between p and p, increases, if the point of intersection 
