338 PROCEEDINGS OF THE AMERICAN ACADEMY. 



did not have time to try whether the nionouitro compound could be 

 obtained with a still more dilute nitric acid. 



The agreement between the nicking points of our triiodbenzol, 181°, 

 and triioddinitrobenzol, 210 . with those obtained by Istrati and 

 1 ■ .rgescu, * 182° L8 I and 210 --J12°, establishes the identity of these 

 substances beyond a doubt. The triioddinitrobenzol also gives us the means 

 of proving their constitution. For this purpose 0.5 gram of the triioddi- 

 nitrobenzol were heated with 0.5 gram of aniline; this proportion gives 

 about six molecules of aniline to each molecule of the dinitro compound. 

 The beating was carried on for two hours on the steam bath, and the 

 product, a dark red solution, was treed from the excess of aniline by 

 washing with dilute hydrochloric acid, when it Formed a dark red sticky 

 mass, which was purified by working it well with a rod under dilute 

 hydrochloric acid and then crystallizing it from alcohol. It showed the 

 constant melting point 181°, which agrees sufficiently well with 179 . 

 that given by Palmer and one of usf for the trianilidodinitrobenzol 

 made from the tribiouidinitrobenzol Br. 1.3.5. (N0 2 ) 9 2 . 4. This 

 proves, therefore, that the triiodbenzol melting at 181° has the iodine in 

 the position 1 . 3 . 5, as would have been inferred from its preparation 

 from triiodaniline, which according to the analogy of the chlorine and 

 bromine compounds should have the symmetrical constitution. 



* Bui. Soc. Sci. Fiz., I. 62, G6. 

 t These Proceedings, XXIV. 111. 



