160 A. L. DAY MINERAL RELATIONS FROM LABORATORY VIEWPOINT 



9500 

 (looC) 



I division =10 minutes 



Figure 5. — Melting Curves of Orthoclase 



The area included within the dotted line represents the approximate distribution of the 

 latent heat of fusion for different rates of heating. (Prom Day and Allen, loc. cit.) 



