Dr. Hofmann on the Metamorphoses of Indigo. 511 

 cent, platinum, from which is deduced the formula CI H, Cjg 

 rB ^ V N + CI2 Pt, which requires 26*22 per cent. 



Action of fused Hydrate of Potash on Dibromisatine 

 [Bibromisaiine, Erdmann, Bromisatinese, Laurent). 



F. Dibromaniline (Amabrophenese). CjgK t> ^ /■ N.* 



By the distillation of dibromisatine with hydrate of potash 

 there passes into the receiver likewise an oily body, which so- 

 lidifies into a crystalline mass. By washing these crystals with 

 water till all trace of ammonia, which is formed in the last 

 stage of the distillation, is removed, and dissolving in boiling 

 alcohol, they are obtained of a shining white appearance. 



a. Comjiosition of Dibromaniline. 

 A very sure conclusion on the composition of this body 

 may be drawn from analogy. I therefore contented myself 

 with a determination of the carbon and hydrogen. 



On burning with chromate of lead the following results 

 were obtained : — 



0-2795 grm. of the substance gave 0*2950 grm. of carbonic 

 acid and 0*065 grm. of water. These numbers correspond 

 in the 100 parts to 



Carbon .... 28*77 

 Hydrogen . . . 2*40 



Corresponding formula, Cjg^ ti^ [^N, as is shown by the 



following : — 



Theory, Experiment. 



12 equiv. Carbon . 

 5 ... Hydrogen 

 2 ... Bromine . 

 1 ... Nitrogen . 



1 ... Dibromaniline = 3096*17. 



* The dibromisatine employed was prepared by long digestion of bro- 

 misatine with bromine. The substance crystallized from alcohol and 

 burned with chromate of lead gave the following results : — 



406 grm. of substance gave 0-4715 grm. of carbonic acid and 0047 

 grm. of water. These numbers correspond in the 100 parts to 



Carbon 31-62 



Hydrogen 1-28 



and indicate the formula Cja-^ o^ i- NO4, which requires 



Carbon ..*..-. .31-83 



Hydrogen ..... 1*00 . . 



