

497 



ringly soluble in cold, readily soluble in boiling water, the new com- 

 pound requires only to be once or twice recrystallized. Thus puri- 

 fied, this substance forms long prismatic crystals, frequently inter- 

 laced, white as long as they are in the solution, but assuming a 

 slightly yellowish tint when dried, and especially when exposed to 

 1 00 : they are readily soluble both in alcohol and in ether. The 

 new body exhibits a distinctly acid reaction ; it dissolves on applica- 

 tion of a gentle heat in potassa and in ammonia, without, however, 

 neutralizing the alkaline character of these liquids ; it also dissolves 

 in the alkaline carbonates, but without expelling their carbonic acid. 

 The new acid fuses at 211 C., and sublimes at a somewhat higher 

 temperature, with partial decomposition. The sublimate consists of 

 small prismatic crystals. 



Analysis proves this substance to contain 



C e H 4 N 4 2> 



a formula which is confirmed by the analysis of a silver-compound, 



C 6 (H 3 Ag)N 4 2) 



and of a potassium-salt, 



C (H 3 K)N 4 2 . 



The analysis of the new compound shows that, under the influence 

 of nitrous acid, nitrophenylenediamine exchanges three molecules of 

 hydrogen for one molecule of nitrogen, three molecules of water 

 being eliminated. 



Nitrophenylene- New acid. 



diamine. 



I do not propose a name for the new compound, which can claim 

 but a passing interest, as throwing, by its formation, some light on 

 the constitution of nitrophenylenediamine. 



The composition of the new acid, and of its salts, shows that in the 

 crimson-red base four hydrogen molecules are still capable of re- 

 placement ; in other words, that this body contains four extra-radical 

 molecules of hydrogen. The result of these experiments appears to 

 confirm the view which, in the commencement of this Note, I have 

 taken of the constitution of this body ; at all events, the mutual 

 relation of the several bodies is satisfactorily illustrated by the 

 formulae 



