301 



Angles: Observed: Calculated: 



c:o (001): (111)=* 54°5T 



0:o (lll):(iri)=* 72 31 — 



O:m(lll):(110)=* 50 n — 



c:m(001):(110)= 14 41 74°49' 



m:m(110):(lT0)= 91 30 91 32 



c:o> (001): (225)= 50 59 51 5 



w": m ("225) : (TlO) = 23 42 23 44 



A. distinct cleavabiiitj was not found. 



The crystals are dicliroitic in a way analogous to that found in 

 the case of the cw-derivative. On m is the angle of extinction oblique. 



§11. From a solution containing both 

 the cis- and ^;vT7z.s-derivatives, crystals of 

 the form shown in tig. 9 were deposited, 

 which imitate in a striking way the 

 aspect of the cw-deriv^ative. In contradiction 

 with those of this substance, however, 

 the crystals of this kind do not decay, 

 nor do they lose any water of crystalli- 

 sation. Moreover, they have often rather 

 oscillating angular values in the zone of the 

 prism, and uneven faces. Their dichroism 

 is analogous to that observed with the 

 pure cis-, or ^ya^^ó'-compounds. 



Monoclinic-prismatic. 

 a : /^ : c = i,0J69 : 1 : 0,9030 ; ,5 = 66° 16'. 



Forms observed : m z=z[110J predominant 

 and lustrous; 6>^[111J, large, giving 

 good reflexes; 6 = [010], much smaller 

 than ??i;c^[001], small, but well measu- 

 rable. The external form is prismatic cis- + <ra>?s-Dinitro-dietbylene- 



. A t^u -^ diamineCobalti-Nitrite. 



towards the c-axis. 



Fig 9. 



Angles : Observed 



c:m = (001):(110)=* 72°52' 



Ö:W = (010):(110)=* 47 3 



o o =(lll):(in)=* 64 291/2 



m:m = (110):(irO) = 

 CO =(001):(111) = 

 O:m=(lll):(110) = 



bo =(010)^(111) = 



Calculated ■ 



