323 



to HiLPKRT the sample III contains free carbon together with a 

 new higher carbide, possibly FeC, or FeC. The diversity of the 



■ 13'- 

 -12'- 



11'- 

 -10'- 



- 9'- 

 8'- 



- 7'- 



- 6'- 



- 5' - 



■ 4' - 



■ 3' - 

 • 2'- 



- 1' 



0° 



J — I — \ L 



t200^ 



Fiff. 4. 



results may, therefore, bo due to the presence of two oi' even three 

 carbides or mixtures of the same, which is interesting from a 

 metallurgical point of view. 



Ferrosllicon (atomic percentage of Si 30, Tammann, 6^ ^ 450°) 

 Conglomerate of mixed crystals. The saturated mixed crystal with 

 33,3 atom. perc. Si has the same composition as the compound, Fe^ Si 

 whose existence is still uncertain ^). The hard material could be 

 finely polished. The substance is characterized by a powerful negative 

 rotation increasing continuously from the violet to the red and by the 

 absence of singularities in the dispersion curve. (Tab. 2). 



,=f{l) 



TABLE 2. 

 Ferrosilicon (saturated; 



Tammann. 



i) H. Tammank und W. GutRTLKR, Zeilsclir. f. Anorg. clieni. 47, p. 103,191)5. 



2i*- 



