( li>3 ) 



The l-2AS-tnbwmo-S-o-(U?utro-toIue7ie melts at 22^ ; the '1-2-3-5- 

 ti'ibromo-^-Q-dinitro-toIuene at 210°. 



Like the two ifr//>ro?»o;;6»/?«f:'?z^^.sMhemselves, these substances are again 

 quite isouorp/ums and owing to peculiar twin-formation, they so 

 resemble each other, that at tirst sight we cannot distinguish the 

 two kinds of crystals from each other. 



a. i''2-4:-()-tril>ro}uo-3-5-(Unitro-toluene. 



C„ Vn- . Br . Br . (NO,) . (NO,) . (CH^); melting point 220 ^ 



(6) (4) (2) (5) (3) (1) 



From benzene this substance crystallises in large ai)parenlly ([ua- 

 dratic, colorless crystals which are nearly all twins, — ^vhich may be 

 recognised at once by a very fine diagonal on two of the broadest 

 planes. We also may obtain needle shaped or very elongated thick 

 pillar shaped crystals. The planes are generally angular and give plural 



Fis. 1. 



