WHICH NITEOGEN IS SUBSTITUTED EOE HYDEOGEN. 
707 
0*453 grm. of bromoiodobenzol gave 0*4082 grm. carbonic acid and 0*0612 grm. water. 
[Calculated. 

Pound. 
I 
^6 
72 
25*44 
24*58 
h 4 
4 
1*41 
1*50 
Br 
80 
28*27 
— 
I 
127 
283 
14*88 
100*00 
— 
Platinum-salt of the Hydrochlorate of Diazoiodobenzol , € 6 H 3 IN 2 , HC1, Pt Cl 2 , 
forms small bright yellow clusters of needles. 
Diazoiodobenzolimide, 
(G 6 H 3 IN 2 )" 
H. 
■N, 
forms yellowish-white crystals, which are readily fusible, and pass over on distilling 
with water as a yellowish oil, soon solidifying. This likewise is of a peculiar aromatic 
ammoniacal odour. 
Diazoiodobenzol , € 6 H 3 IN 2 , 
is obtained as a yellow explosive precipitate. 
DIAZONITEOBENZOL COMPOUNDS. 
The remarkable isomerism observed between a and j3 nitraniline, and hitherto left 
unexplained by any chemical theory, likewise extends, as I have shown upon a former 
occasion, to the double compounds which I have described as a, and (3 Diazo-amidonitro- 
benzol. This isomerism, however, is somewhat less striking, since these bodies retain 
one-half the nitraniline required for their formation in the original condition, as will be 
clearly seen on examining the rational formula 
r€ 6 H 3 (NG 2 )N 2 ) 
l€ 6 H 4 (N0 2 )H 2 Nj 
which I assign to these bodies. The simple diazo-compounds derived from these isomeric 
nitranilines cannot, however, be viewed similarly, and it was impossible therefore to 
decide a 'priori the question of their isomerism. The experiments presently to be 
described nevertheless leave no doubt that a similar isomerism exists between the 
several members of both series, and that, although of identical composition, differences 
in their physical properties become manifest, which are as striking as those observed 
between the original bases. 
5 B 
MDCCCLXIV. 
