OP ARTS AND SCIENCES. 143 



The triamidotrinitrobenzol can be made conveniently also from the 

 mixture of tribromtrinitrobenzol and tetrabromdinitrobenzol obtained 

 in purifying tribromtrinitrobenzol, thus utilizing directly a secondary 

 product, which could be separated into its pure constituents only with 

 a great outlay of time and work. For this purpose, the mixture is 

 treated with alcoholic ammonia in the manner already described when 

 speaking of the preparation from pure tribromtrinitrobenzol, and the 

 product freed from the tetrabromdinitrobenzol, which is not attacked 

 by alcoholic ammonia under these conditions, by boiling and washing 

 with benzol or chloroform after the washing with alcohol. 



The composition of the substance after being dried at 100° was 

 determined by the following analyses. 



I. 0.2352 grm. of the substance gave on combustion 0.2370 grm. of 



carbonic dioxide and 0.0544 grm. of water. 

 II. 0.2346 grm. of the substance gave 0.2342 grm. of carbonic 

 dioxide.* 



III. 0.2186 grm. of the substance gave 60.4 c.c. of nitrogen under 



a pressure of 770 mm. and a temperature of 19°. 



IV. 0.1058 grm. of the substance gave 29.6 c.c. of nitrogen under a 



pressure of 765 mm. and a temperature of 20°. 



III. IV. 



32.19 32.22 



Properties. — As obtained from the action of alcoholic ammonia on 

 the tribromtrinitrobenzol, the triamidotrinitrobenzol forms an amor- 

 phous powder of an orange or yellow color, according to the conditions 

 under which it was prepared ; crystallized from aniline or nitrobenzol, 

 it forms small rhombic plates of a pale yellow color. It decomposes 

 without melting above the boding point of mercury, and is nearly, 

 although not completely, insoluble in water, alcohol, ether, benzol, 

 chloroform, or glacial acetic acid. It dissolves in andine, or in nitro- 

 benzol, and, as already stated, can be obtained in crystals from these 

 solutions. Cold strong sulphuric acid slowly dissolves it, forming a pale 

 yellow solution, but on dilution the unaltered substance is precipitated. 

 Dilute sulphuric acid, or dilute or strong nitric or hydrochloric acid, 

 has no action on it, and when the substance was suspended in alcohol 



* The hydrogen of this analysis was lost. 



