342 



Dr. Hofmann's Researches on the 



[June 16, 



upon this subject, attributes to this compound a formula differing from the 

 expression at which I had arrived. According to M. Schiff, aniline-blue 

 is not a triamine, as I had found, but a tetramine, which may be looked 

 upon as a combination of rosaniline with triphenylamine, 



C33H3,N„ H,0=C,oH,3N3, H,0 + (C3H,)3 N. 



This formula is less simple than the one I had given ; it attributes to 

 aniline-blue a constitution not supported by analogy, and involves the 

 necessity of assuming, for the formation of this substance, a reaction which 

 ceases to be a simple process of substitution. 



M. Schiff's formula is given as the result of an unfinished inquiry, and 

 the author himself appears to have but limited confidence in its correct- 

 ness. Nevertheless, the publication of his Note imposed upon me the 

 duty of confirming by new experiments the result of my former researches 

 upon this subject. 



The material used in these new experiments was likewise furnished to 

 me by Mr. Nicholson ; it had been taken from the product of an operation 

 perfectly different from the one which had supplied the first specimen. 

 In the following synopsis the experimental numbers of the former analyses 

 are marked (a), in contradistinction to those (S) recently performed. 



Free Base. 









C3SH33N3O 



(Schiff). 

 C33 456 



80-85 





(Hofmann). 

 456 



83-36 



H3, 36 



6-38 



H33 



33 



6-03 



N, 56 



9-93 



N3 



42 





16 



2-84 







16 . 



2-92 



564 



100-00 





547 



100-00 





Analyses (Hofmann). 



a. 



b. 





Carbon '83-81 



83-89 



83-13 







Hydrogen 6*20 

 Nitrogen — 



6-18 



6-04 



8-16 





Chloride. 





C3,H3,N,C1 







C33H3,N3C1 





(Schiff). 







(Hofmann). 



C38 



456 



78-28 





456 80-64 



H3. 



35 



6-01 



H30 



32 5-66 





56 



9-61 



N3 



42 7-43 



CI 



35-5 



6-10 



CI 



35-5 6-27 



582-5 100-00 



565-5 



100-00 



