Ferguson and Merwin — The Ternary System. 109 



a check upon the experimental methods employed. The 

 curves IF and 4G are perhaps the best illustrations of 

 what reliance may be placed upon the methods. Each 

 of these curves represents the work of several investi- 



Fig. 12. 



SiO. 



mo 



SCaOSMgOeSiO; 



X 



ChOJtgO-Z&Qv 



mi y& .wP' 



T&O: 



^caozsio /ms^ 



'^& ZCaOffyO Z5iO t 



-ho. 



fsoo . 



ZCaOSLO, 

 Z130 



a.ZCajO-5iO e 



GuONgOSiO;. 



•Boundaries , 



Isotherms determined, Isotherms by extrapolation •, 



-I— »~t-,|^i3 Solid solutions 



ZQOO 



Fig. 12. — A concentration diagram somewhat similar to that given in fig. 

 8 upon which the isotherms showing the temperatures of complete melting 

 of the various compositions are drawn. The diagram is on a wt. per cent 

 basis. 



gators ; 2, F, and 5, G were determined by N. L. Bowen, 

 1, 2, and 4, 5, by ourselves. The agreement here obtained 

 is of the order usually found between experiments of the 

 same series, but in this case somewhat exceeds that 

 usually obtained by us when the identical apparatus 

 was not used for all experiments. A somewhat similar 



