96 



Pig. 8. — Same conditions as in Fig. 

 Lower surface, polished and etched. 

 X 50 



-Heated to 800° C. for 1 hour, 

 x>oled in furnace, x 50 



Fig. 10.— Heated to 800° C. 

 cooled in the furnace. 



for 1 hour, 

 X 50 



Fig. 11. — Mi'ltcd at 5."'>0° C. and cast in 



iron chilled mold. Vertical section. 



X 50 



