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ïn tiie ligs. 8, 9 and 10, I have drawn projections for the cases 

 1, 2 and 3. Fig. 8 corresponds to case 1, tig. 9 to case 2 and tig. 

 10 to case 3. The meaning of the different lines is indicated by 

 letters; thus A denotes the solid substance A, B the solid substance 

 B and AB the solid substance AB, L denotes liquid and G gas. 

 E and E' are the two eutectic points, a and a' the triplepoints of 

 pure A and B. 



The ^-/-projections show further that we have here a three jihase 

 line for AB -\- L -{- G consisting of two branches passing continuously 

 into each other, and that we must find here the phenomena discussed 

 in the preceding paper, on a larger scale. As already appeared from 

 the p-.??-sections, the triplepoint has split up into two points F and 

 F\ In the point F there is contact with the line for AB -j- L and 

 in F' with the line for AB -^ G. 



Though for the systems A B -\- L and A B -\- G we have to deal 

 with systems of two components in two phases, they behave as 

 monovariant s^^stems, because the concentration of the two phases is 

 identical. This is however not the case for the system liquid A B -\- 

 vapour, and this is the reason why the line for L -\- G, which begins 

 in F, cannot be represented; at constant temperature, the pressure 

 is here still depending on the volume. 



The point F does not correspond to the maximum three phase 

 temperature, and that is the cause of the analogy with the case 

 discussed in the preceding paper. 



For the cases 1 and 2 the three phase line must have the direction 

 of the melting line at the melting point F, as van der Waals has 

 proved. As in most cases vi ]> Vg, the melting line runs from the 

 melting point to the right. This involves the necessity that the point 

 F, (see fig. 8a) lies below R, i. e. at a pressure smaller than that 

 corresponding to the maximum three phase temperature. If we there- 

 fore proceed to higher pressure, the succession is : F\ F, E. It is 

 also obvious from the relative situation of these three points, that 

 in figs. 4 and 5 the pressure corresponding to the maximum three 

 phase temperature ECS, must lie somewhat above the melting point 

 pressure e' c'. 



Let us now consider the rare case that vi <^ Vs, so that the melting 

 line runs to the left, as is represented in fig. 8b. Then the point F 

 lies above the point R, and the succession towards higher pressure 

 is F', R, F. A consequence of this situation is, that in this case the 

 two three phase pressure lines ecs and c^e^Si (figs. 4 and 5) must 

 coincide between the pressures corresponding tot F' and F. This, 

 however, not being the only modification which occurs in figs. 4 and 



