Diopside — For sterile — Silica. 



221 



Schreinemakers.* No attempt is made to discuss all possible 

 cases. Attention is confined to systems which lead up to that 

 under investigation. 



One simple case is shown in fig. 8. Here the two compon- 

 ents A and B form a complete series of solid solutions and 

 each forms a eutectic with C. These relations, in the binary 

 systems, are shown in the diagrams erected on the sides of the 



Fig. 8. 



triangle. As will be noted, the arrows indicate, in the ternary 

 diagram, the direction of falling temperature, a method main- 

 tained throughout the present paper. 



All liquids of composition represented by a point in the area 

 ABDE may exist in equilibrium with a solid solution A + B. 

 All liquids in the area DEC may exist in equilibrium with 

 C and all liquids lying along the curve DE may exist in equili- 

 brium with both solid C, and a solid solution A + B. 



Fig. 9 shows the relations at any temperature T°. LNM is 

 the isotherm for temperature T°. The phases present for 

 various compositions at this temperature are as follows : 



*Zs. phys. Cheni., 1, 169 ; li, 547. 



Am. Jour. Sci.— Fourth Series, Vol. XXXVIII, No. 225.— Sept., 1914. 

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