508 Dr. Hofmann on the Metamoyhoses of Indigo. 



line. To banish all doubt, however, I determined the carbon 

 and hydrogen. 



The following results were obtained on qombustion with 

 chromate of lead : — 



0'4152grm. of thebrominated base gave 0'6^6S grm. of car- 

 bonic acid and O'l^OS grm. of water. The corresponding num- 

 bers in the 100 parts found and calculated are as follows: — 



'12 



m- 



The formula is C,c -< •„ ^ I- N. To control this formula 



the platinum double salt was prepared and analysed : 0*462 

 grm. gave 0-161 grm. = 26" J 9 per cent of platinum. 



Atomic weight calculated from this . . 2125*80 



Theoretical atomic weight 2130*35 



This agreement is sufficiently close. 



b. Properties of Bromaniline. 



The bromine base resembles in so high a degree the chlo- 

 rine, that I shall have little to say on this point. It crystal- 

 lizes also with the same facility in large, colourless, regular 

 octahedrons, which in appearance can be as little distinguished 

 from the chlorine base as the bromide from the chloride of 

 potassium. The same similarity extends to its smell, taste 

 and other properties. Its point of fusion, however, lies some- 

 what lower than that of the chlorine compound. At 50° cent, 

 it melts to a violet oily liquid. On solidifying, the thermo- 

 meter descends to 46° cent. 



The salts of this base, like those of aniline and chloraniline, 

 impart a yellow colour to pine-wood, and its watery solution 

 communicates to chloride of lime a violet tint, much weaker 

 than that caused by aniline, but, on the other hand, much 

 stronger than that produced by chloraniline. 



c. Compounds of Bromisatine. 



What I have said with regard to the formation and prepa- 

 ration of the compounds of the chlorine base applies for the 

 most part to the salts of the corresponding bromine base. I 

 have only investigated some of these fully. 



Oxalate of Bromaniline. C^ O3, Cjg "I -r^ f ^^ HO. 

 On adding a watery solution of oxalic acid to this base 



