1215 
in figs. 1 and 2 by the points 1’, 2’ and 3’; those of #" by 1", 
2" and 3". The points 1’, 2’ and 3’ are situated in the immediate 
vicinity of the points 1, 2 and 3; they form the anglepoints of a 
triangle 1’ 2’ 3’, which represents the concentration-region of the 
equilibrium ZE’. Triangle 1" 2" 3" represents the concentration- 
region of E". 
In accordance with a the line 123 and the triangles 1'2'3' and 
1’2"3" must not have one single point in common, in accordance 
with 5 the line 123 must be situated between the two triangles ; 
in accordance with c 1'11", 2'22" and 333" are straight lines and 
is 11'=11", 22'— 22" and 33' —= 33". Consequently we obtain a 
diagram as in figs. 1 and 2. 
Consequently at Tr + AT’ two triangles arise from the straight 
line which occurs at the temperature 7’p; reversally the two triangles, 
which occur at Tr AT coincide at Tr into a straight line. 
The transitions, discussed for figs 1 and 2 will occur when the 
ternary equilibrium / consists of 3 liquids or of 2 liquids and vapour, 
or of 3 kinds of mixed crystals, or of a mixed crystal + liquid + 
vapour etc. 
When one of the phases e.g. #’, has an invariable composition, 
then we obtain figs 3 or 4; when two phases e.g. /, and /, have 
an invariable composition, then we obtain fig 5. 
Fig. 3. Fig. 4. Fig. 5. 
In order to show the rules, mentioned above, we represent of the 
equilibrium Zp the composition 
a I GAS ae oy a 
Fade NRE IRE PEPE EN. 
etc. 
Then the composition of the equilibrium £’ is: 
