S24 
the case of the ternary systems, construct the different concentration- 
diagrams and the type of P, 7-diagram belonging to each of those 
diagrams. Now we shall deduce them, however, without using the 
concentration-diagrams, with the aid of the three main-types 1, HA 
and ILA’, which we have deduced in communication X. 
In main-type I curve (M) is monodirectionable and the 3 singular 
curves coincide in the same direction. Consequently the P, 7-diagram 
has the same appearance as that of a ternary system. In the types 
of P,T-diagram of the ternary systems |fig. 2 (II), 4 (Il) and 6 (ID) 
we let one of the curves represent the (J/)-curve. Then we find 
the following diagrams: 
BDA B TRED i or 
B(M) + B, + B, REEN aa 
Be ROA BA EN 
B BA MPIO TEN 
BIM EERDE overh LATEN 
B LBA RMM ED 
ee ee eee oe 
Herein B, means an onecurvical bundle, 5, a twocurvical bundle 
etc., B(M) indicates a bundle which consists of the (J/)-curve only, 
B(M +1) a bundle, which consists of the (J/)-curve and still 
another curve, ete. 
With the aid of main-type Il A we find the diagrams: 
BM)+B,+B04+M4H4+8B,....- & 
BOS BU 4S) tet Pe ee 
BUM) BO + MD) > a. Seay 
With the aid of main-type If B we find yet the diagrams: 
BM HAB MDB, nn 
BM AEN RRE ML B, rn GE 
The reader himself may easily draw the 12 P,7-diagrams of which 
the diagrams (1)—(12) are the symbolical representations. 
; (To be continued). 
Leiden, Inorg. Chem. Lab. 
