256 PROCEEDINGS OF THE AMERICAN ACADEMY 



of preparation in every way we could devise, and by treating the 

 orange prisms with reagents, which usually convert one stereo- 

 isoineric form into another, but have met with no forms except 

 the two already described. 



Compound of Trianilidodinitrobenzol and Chloroform. 



If in crystallizing the trianilidodinitrobenzol a mixture of chloro- 

 form and alcohol was used instead of benzol and alcohol, dark red 

 well formed short prisms were obtained entirely different from 

 either of the forms just described. The whole of the substance 

 could be converted into these prisms, if the solution in chloroform 

 and a little alcohol was allowed to evaporate at temperatures from 

 50° to 70°. This substance, however, proved to be, not an isomere, 

 but a compound with chloroform, since on heating some of the dry 

 crystals with sodic hydrate and aniline a strong odor of phenyliso- 

 cyanide was perceived. 



Our first attempts to analyze it showed that the chloroform was 

 given up partially at ordinary temperatures, but that to drive off 

 the remainder it was necessary to heat to 100°. Accordingly we 

 proceeded as follows. A quantity of the orange trianilidodinitro- 

 benzol melting at 179° was dissolved in warm chloroform, and after 

 the addition of a little alcohol poured into a large watch-glass to 

 crystallize; when nearly all the chloroform had evaporated, the 

 crystals were pressed as quickly as possible between filter paper till 

 free from adhering chloroform, and then transferred at once to a 

 stoppered glass tube, in which they were weighed. 



I. 1.5012 gr. of the compound lost at 100° 0.3226 gr. of chlo- 

 roform. 

 II. 1.4455 gr. of the substance lost at 100° 0.3059 gr. of chlo- 

 roform. 



Calculated for Found. 



C e H(C 6 H 5 NH) 3 (N0 2 ) 2 CHCl 3 . I. II. 



Chloroform 21.32 21.49 21.16 



The residue was trianilidodinitrobenzol melting at 179°. 



Properties of the Addition Compound of Trianilidodinitrobenzol 

 and Chloroform. — This substance crystallizes in short thick prisms 

 with both terminations well developed, apparently of the mono- 

 clinic system, which have a very dark brownish red color not unlike 

 that of well crystallized potassic ferricyanide, and show a blue re- 

 flex. The chloroform is not securely held, part of it being given 



