( 795 ) 



narrow limits. I believe I have noticed something similar some time 

 ago with a specimen of the Dlbi'omide of 1-3-5 ifö^a^m?*^ presented 

 to me by Prof, van Romburgh ^). Notwithstanding the identical crystal 

 form the preparation made by addition of bromine to the hydro- 

 carbon showed slight optical differences with that prepared from 

 divinylglycol by means of PB}\. 



And although I will not as yet venture 

 to give a decision one way or other, I 

 fancy that on account of the phenomena 

 described here the matter is of sufficient 

 importance to be brought to the notice of 

 chemists. 



§ 4. Tri-p-Chloro-Triphenylcarbinol. 



(C« H, Cl)3 : C-OH : m.p. 98° C. 



Crystallises from ethyl alcohol in colourless, 

 strongly refracting needles, also from ether 

 -|- ügroïn. The crystals possess great lustre 

 and are well constructed. 

 Rhombic-bipy ramidal . 



a : b : c = 0,6009 : 1 : 0,978L. 



Forms observed: m=i\i^O\, yields ideal 

 reflexes; q = |011|, also yielding irreproach- 

 able images; ^ i= jOlOj and p = |210|, 

 narrow but easily measurable. The habit 

 of the crystals is elongated towards the 

 c-axis. Crystals from ethylalcohol are short 

 prismatic and still exhibit the forms o = |133| 

 and 5 = |102|, generally reflecting badly. 



■nt 



'^ 



Fig. 3. 



Tri p-Ghloro-Triphenyl- 



carbinol. 



Measured : 



m : q = (110) : (Oil) = --68° 53 V; 

 m : b = (110) : (010) = *59° 0' 

 m : m = (110) : (ÏÏO) = QT 

 q: Ó — (Oil) : (010) = 45' 

 q: q = (Oil) : (Oil) = 88^ 

 b: />r=(010):(2J0)=: 42 

 JJ -.111 = (210): (110)= 16 



Calculated 



1) Compare Trans. Chemie. Soc. (1908) p. 517—524. 



