146 PROCEEDINGS OP THE AMERICAN ACADEMY. 



from alcohol and benzol, thick rather blunt rhombic plates, the obtuse 

 angles of which are frequently bevelled by two planes. They show a 

 tendeocy to form groups with the members superimposed, and have a 

 slight yellowish tinge. The substance melts at 175°; and is very sol- 

 uble in chloroform, acetone, or carbonic disulphide ; slightly soluble in 

 ethyl or methyl alcohol either cold or hot ; insoluble in cold, soluble in 

 hot glacial acetic acid ; essentially insoluble in ligroin, oi* in hot or cold 

 water.' The best solvent for it is a mixture of benzol and alcohol. 

 Strong hydrochloric or sulphuric acid has no apparent action on it. 

 Fuming nitric acid dissolves it when hot. It suldimes easily, and in this 

 way feathery ivory-white crystals are obtained sometimes over a centi- 

 meter in length. 



Action of Aniliue on Trichlorhromdinitrohenzol. 



When one gram of trichlorbromdinitrobenzol was warmed gently with 

 a slight excess of freshly distilled aniline, it went into solution forming 

 a cherry-red liquid, the color of which became deeper on longer heating. 

 To obtain the product the liquid was poured into a large quantity of 

 water, acidified with hydrochloric acid, and the crimson precipitate formed 

 in this way thoroughly washed, and crystallized from a mixture of alcohol 

 and benzol, until it reached the constant melting point 175°-176°. 

 This showed that the substance was the bromdinitrotrianilidobenzol 

 CGBr(NO.,)o(CGH6NH)3 obtained by W. D. Bancroft and one of us* 

 from tetrabromdinitrobenzol and aniline. In this case it was formed by 

 the replacement of the three atoms of chlorine by three anilido groups. 



Behavior of Trichlorhromdinitrohenzol ivith Sodic Ethylate in the Cold. 



Five grams of trichlorbromdinitrobenzol dissolved in anhydrous ben- 

 zol were mixed with the sodic ethylate made from twenty-five grams of 

 absolute alcohol and one gram of sodium, which gave the proportion of 

 three molecules of the ethylate to each molecule of trichlorbromdinitro- 

 benzol. The two substances reacted at once, since the liquid took on a 

 bright scarlet color as soon as they were mixed, and tliere was also a 

 slight evolution of heat. To complete the reaction the mixture was 

 allowed to stand three days at ordinary temperatures, during which time 

 a heavy precipitate was deposited, and the color changed to a yellowish 

 red. The precipitate was filtered out, washed with alcohol, and then dis- 

 solved in water. This solution gave a strong test for sodic nitrite with 



* These Proceedings, XXIV. 293. 



