78 Upon a Fourth Monobromphenol. 



This tendency seems, therefore, to be a property of those 

 combinations, which, according to my hypothesis,* founded on 

 the supposition of unequal valencies of the benzol hydrogen, are 

 constructed unsymmetrically. Hitherto, I have not observed 

 anything as to a direct transformation of my new bromphenol 

 into either of those already known ; it will, however, probably be 

 effected. At all events, we have to point out, in opposition to 

 the isomeres, the decomposition by distillation to which the 

 fourth bromphenol is subject. 



To characterize the molecular combinations, I have yet to 

 observe, that also a — and h — dinitrc — p — xylol f crystallize to- 

 gether, forming a combination of one and the same melting- 

 point, and that likewise a chemical combination of butyl- and 

 crotonyl-alcoholj exists, showing the same boiling-point. An 

 investigation of such combinations, principally of aromatic 

 bodies, will surely be of great importance in rendering our views 

 on this subject clear. 



Marburg, July, 1883. 



* Journal prakt. Chem., (2) 17, 428. 

 f Jahresb. d. Chem., 1881, 399. 

 % The same, 596. 



