176 Ferguson and Merivin — The Ternary System. 



These results, taken in conjunction with the results 

 obtained in the study of the fields corresponding to these 

 solid solutions, which are given in the previous paper, 

 make reasonably certain the existence of the compound 

 5Ca0.2Mg0.6Si0 2 , and of an area of solid solution which 

 extends from this compound toward the calcium meta- 



Fig. 2. 



A? 



CaO MqO-2S,0, 



T\ 



5Cc.O 2MqO-6S;0; 



3CaO-2SiO, d 



2CaO-M<)0-2S ; 



'|-- ; '- : l Wollastomte Solid Solhs 



» » « » KF.vl Pseudowollasfomrc & WollasToniTe Solid Sol'ns 

 Arrows show direction of falling temperatures. 



Compound} 



Fig. 2. The part of fig. 1 which deals with the calcium metasilicate and 

 related solid solutions. 



silicate-akermanite line and joins with the area of wollas- 

 tonite solid solutions. The compound 5Ca0.2Mg0.6Si0 2 

 evidently does not form complete solid solutions with the 

 wollastonite-diopside series of solid solutions. The link- 

 ing together of the solid solutions of the diopside series 

 and akermanite with those of the akermanite series and 

 the compound 5Ca0.2Mg0.6Si0 2 naturally results in the 



