798 



then fig. 4 represents tlie plienoiiiena sehematioall y perfectly, al least 

 as far as the principal features are concerned, though the situation 

 of the vapour lines is much more one-sided than has been drawn 

 here. It is, however, not impossible, as Dr. Morey observes, that 

 also tlie binary compound yields critical endpoints, but this being 

 still unknowMi at the moment, we can leave this possible compli- 

 cation undiscussed for the present. Now the system studied by 

 Dr. MoREY. however, is certainly still somewhat more complicated 

 than that indicated in fig. 4, for there occurs another ternary com- 

 pound there, viz. K^Si^Of,H^O. This ternary compound gives no 

 critical endpoints. The figure, however, changes only little, also 

 when this compound is considered. 



Fig. 5. 

 D^ Ihc least volatile ; B more volatile than C' ; A very volatile. 



This change will be applied later when the system has been more 

 closely investigated; probably K^SiJJ^H^^O will occur at lower 

 temperature, KHSi^Oj at higher temperature. 



In any case it seems probable to me that what is typical of the 

 said ternary system is indicated by fig. 4, and so this figure can 

 . |)robably render good services as a guide in the continued research. 



Case 10. Up to now cases have been considered which may 

 present themselves foi' ternary systems with one volatile component. 



