224 Proceedings of the Royal Irish Academy: 



felted needles, which melted at 185-186° C, and were soluble in chloroform 

 and alcohol. It gave on analysis the following results : — 



0T150 gram of the substance gave 0.1023 gram of silver bromide, 



corresponding to Br 37 - 85. 

 C„H 7 Br (NO s )gNH requires Br 23;6 

 CHjBr, N'Uj.XH requires Br 38-3 

 C 13 H 5 Br,(N0 3 j 8 !NH requires Br 48-t 



Hence the substance is dibromo-2.I0-diuitro-diphenylaniine. 



V I Action of Bromine on i.lO-IHnitru-Iiipli.enyiami'iie. 



1 gram i >f 4.10-dinitro-diphenylamine was brominabed in a manner 

 similar to thai described I'm the 2.10-dinitrq compound. On adding the 

 bromine solution hydrobromic acid was evolved; and on standing a pale- 

 yellow solid separated, which was purified by recrystallisation from 

 chloroform. It consisted ol minute, very palc\elhiw needles melting at 

 l'47 C.'j and it was identical with the yellow substance obtained bj the 

 action of bromine on tl rresponding nitrosamine (see VIII, below). 



VII. Action E n.2.lQ-J)initro-l)iphenylnitrosamine. 



In a previous communication bj one of us and Miss P. Ryan two 

 somewhat impure dinitro-diphenylnitrosamines were obtained from 

 diphenylnitrosamine and 4-nitro-diphenylnitrosamiiH n-.-pectively. These 

 iraiiiins were employed in this and the following experiments. 



One gram of crude 2.10-dinitro-diphenylnitrosamine was brominated in 

 the manner alp ed; The bromination mixture was allowed to 



remain in a bright place foi aboul ten days, during which time nq evolution 

 of hydrobromic aeid was noticed. The chloroform solution was evaporated 

 t" dryness; and the yellow BoUd residue was recrystallised from chloroform 

 and alcohol. It was found to consist "i two substances, one al bright yellow 

 compound melting at 18;V (...md identical with that described in V, above. 

 The other had a pale yellow colour, melted about '2-iv <_'., and was less soluble 

 in chloroform and alcohol than the first ; it proved to be identical with the 

 substance melting at l'47 C, described in VI, above. An analysis of this 

 subst t <• the following result: — 



Oi 1 . m of the subslanc _ "741 gram of silver bromide, 

 responding to Br 38*2 



l II Br, Nn.i.Ml requires Bi 383 



1 he substance was therefore dibromo.-4.10r'dinitro 1 dipheuylamine. 



