(2) 
also in the systems formed from water, and phenol with common 
salt or aniline or ethylie-aleohol. 
The second case, viz. the appearance or disappearance of a plait- 
point on the area of the ¢-surface itself and not on its border, may 
arise in different ways. 
It occurs, for example, when a plait divides into two other plaits 
so that it also occurs with the connodal line which represents the 
equilibrium between the two liquid phases. According to the resear- 
ches of Mr. ScHREINEMAKERS this case occurs, most probably, in 
the system: [water — alcohol — succinonitrile] at about 4°. 
There is however, another case which Mr. SCHREINEMAKERS has 
now discovered experimentally. Let us suppose that at a certain 
temperature T the ¢-surface is at every point convex from below. 
On changing the temperature a plaitpoint may now appear on the 
¢-surface, which, on a further change of temperature, may develop 
into a plait in such a way that connodal lines with two plait- 
points are produced. We then have the case that at this tempera- 
Ph. ture the three compo- 
nents, taken in pairs, 
are completely miscible, 
but that ternary mixtures 
exist for which this is 
not the case. 
Mr. SCHREINEMAKERS 
has realised this in the 
system: [water (W) — 
phenol (Ph) — acetone 
(Ac)| for which the con- 
nodal lines for 30°, 50°, 
A, 88°, 80°, 85° and 87° are 
diagrammatically repre- 
sented in figure 1. Their 
W 
ligt 
exact positions can be found by means of the following tables. 
Composition of the solutions on the connodal line at 30°. 
1, W92 92.3 91 884 81 70.9 62.1 5116 39.8 28:9 Ain 
Whe 0. LY 4 7.6 15 23.4 289 349 409 LAN ee 
Ph 8.6 8B 4 A 6 Os En 
of, WI184 17.2 17.9 19.1 21.1 22.6 252 27 ten 50 Tea 
bj Ac 341.358 81.1129 99 AL AG B 0 oe 
O/,Ph47,5 57 64 68 69 70 70.2 70.6 70 69.5 69 
