H HAGA AND F. M. JAEGER. ON THE SYMMETRY OF THE RÖNTGEN-PATTERNS 



OF TRIGONAL AND HEXAGONAL CRYSTALS, AND ON NORMAL AND ABNORMAL 



DIFFRACTION-IMAGES OF BIREFRINGENT CRYSTALS IN GENERAL. 



JÊÊ^ 



m 



Fig. ,5. 

 Phenakite. Plate parallel to (72T0). 



Fig. 6. 

 Dolomite. Plate parallel to (0001). 



Fig. 7. 

 Dolomtle. Plate parallel to (OlTO). 



Fig. *. 

 Dolomite. Plate parallel to (r2ro). 



Proceedings of the Acad, of Sciences, Amsterdam. XVIll. A" 1915/1916. 



