65 



X Laevogyratory LutM-Tripthylenedinmine-CobaJti-iodiile. 



Formula: \Co{Aein\\J, + 1 H/). 



Tliis antipode was prepared in a (piite analogous way to that indi- 

 cated in the case of the dexlrogyratory component, and recrystallised 

 from warm water. The crystals also contain, according to analysis, 

 1 molecule of water of crystallisation. They may grow to considerable 

 size: one individual had a volume of more than 0.5 ccm. 



Flat, dark-red to blood-red crystals, with lustrous faces, which 

 give multiple retlections howc\or, especially in the prism-zone. 



Observed Forms: y>=:{J2()!. lai-gc, but giving multi|)le images; 

 f/ = j011}, also lar'geiy de\ol()ped, and better letlecting tlian ji; 

 ^ = {O'lOj, very lustrous and well rollecting ; r ^ jl()2i. small, but 

 very lustrous and well measurable; /;/ =r }340|, very narrow; 

 <T=z:{101}, very small, and often absent ; ^? =r jlOOj, extremely narrow. 



The habit is somewhat elongated with respect to the c-axis. 

 (fig. 11). 



Rhomhic-hipyramidn/. 

 a: i :c =z 0.8256 : 1 : 0.7395. 



Angular Values: Ob'^erved: Caleidatcd: 



6:p=:(010):(120)= *31° 12' — 

 </:g=(011):(0Tl) = *72 58 — 



6:^ =(010) -.(011) = 

 a:p =(100): (120) = 

 »•:»■ =(102):("02) = 

 r:<7 = (102):(101) = 

 p: 5 =(120): (011)- 

 in\p — (340) : (120) = 



Fig. 11. 



Laevogyratory 



Triethylenediamine- 



Cobalti-ioilide. 



No distinct cleavage was observed ; one parallel to |001j may 

 perhaps be supposed. 



The optical orientation is the same as in the case of the dextro- 

 gyratory compound. 



25° 

 The specific gravity of the crystals at 25° Cis: d =2.288: the 



4 



molecular volume is thus: 278.84. 



5 



Proceedings Royal Acad. Amsterdam. Vol. XVIU. 



