Ferguson and Merwin — The Ternary System. 179 



results so obtained give one a clearer mental picture of 

 the general liquidus-solidus relations than could other- 

 wise be had. The last stages of the crystallization and 

 the products are : 



(1) Compositions lying within the region AEW^ 

 crystallize along the line E15 and give mixtures of pseu- 

 dowollastonite solid solutions of the series AW and 

 silica. 



(2) Compositions lying within the region AWR 2 crys- 

 tallize to form pseudowollastonite solid solutions of their 

 own composition. 



(3) Compositions lying within the region WWiBjB 

 crystallize to mixtures of silica with the wollastonite 

 solid solution B and the pseudowollastonite solid solution 

 W; 15 the final glass has the composition of point 15. 



(4) Compositions lying within the region R 2 R X KJ 

 crystallize along the line J13 to form mixtures of aker- 

 manite with pseudowollastonite solid solutions of the 

 series R 2 Ri. 



(5) Compositions lying within the region RjCTK 

 crystallize to mixtures of akermanite with 5Ca0.2MgO. 

 6Si0 2 and the pseudowollastonite solid solution R x ; the 

 final glass has the composition of point 13. 



(6) Compositions which can go solid along the line 14, 

 13 will consist, when crystallized, of mixtures of solid 

 solutions of pseudowollastonite of the R^W series and 

 of solid solutions of 5Ca0.2Mg0.6Si0 2 of the CF series; 

 and the area representing these compositions is some- 

 what irregular in shape due to the fact that pseudowol- 

 lastonite solid solutions change in composition from R x 

 to W and the 5Ca0.2Mg0.6Si0 2 solid solutions change 

 in composition from C to F. These compositions will be 

 represented by that part of the area which is covered by 

 the lines joining the compositions of the two kinds of 

 co-existing solutions which is not included in the area 

 RjCTK, namely, the area RjWC. The lines joining the 

 compositions of the two kinds of solid solutions which 

 can co-exist are all tangents to WC which is somewhat 

 curved. 



(7) Compositions represented by the small area WBS 

 will crystallize to mixtures of pseudowollastonite solid 

 solution W, wollastonite solid solution B, and 5CaO. 



15 The pseudowollastonite which crystallizes out along 14, 15 and at 15 

 contains a little more silica than solid solution W but these compositions 

 lie too close to W to show upon the diagram (see footnote 14, page 177). 



