298 



m:c =(110): (001)=* 

 m:b =(110): (010) = 



a:s =(100): (410) = 



s:m = (410):(110) = 



a:7n = (100):(110) = 

 m-.q =(110):(0I1) = 



b:q =(010): (011) = 



c:q =(001):(011) = 



No distinct cleavability was observed. 



On [010] feebly dichroitic : tbr vibrations parallel to the c-axis, 

 yellow-orange, for such perpendicular to them red-orange. The angle 

 of extinction on [010] is about 60° with respect to the c-axis, in 

 the acule angle of the axes a and c. The plane of the optical 

 axes is probably [010]. 



§ 8. Trans-Dinitro-diethylenediamine-Cobalti-Nitrate. {Croceo-s&M). 



This compound was obtained from the mother-liquid of the cor- 

 responding cw-derivative, in the form of splendidly developed, red- 

 dish brown, very lustrous and transparent, little crystals. They are 

 evidently identical with those prepared by Werner, and previously 

 described^); also in this case the angular values somewhat differ 

 from those formerly measured. As a new form, b = [010] was 

 found. The external aspect of the crystals is that of hexagonally or 



^co. 



Fig. 6. 

 trans-Dinitro-diethylenediamine-Gobalti-Nitrate. 



octogonally bordered, rather thick crystal-plates. 



Monoclinic-prisma tic . 

 ö^:è:C = l,3040:l : 1,0085; 



^=73°3iv;. 



1) F. M. Jaeger, Zeits. f. Kryst. u. Miner. 39. 565. (1904). 



