46 Notices of the Labours of Continental Chemists. 



soluble in cold water ; boiling water dissolves merely a trace; 

 slightly soluble in nitric acid, precipitated by water. Caustic 

 and carbonated alkalies dissolve it with a red colour, which 

 soon becomes black ; melts a little above 100°, may be vola- 

 tilized without residue, but is often rapidly decomposed with 

 slight detonation. Formula, C 20 H 10 N 6 O 12 , or, according 

 to Laurent's view, C 20 H 10 O + 3 N 2 O. The alkaline 

 solution is at first red, becomes brown, and ammonia is 

 evolved; on the addition of an acid, carbonic acid is given off, 

 and brown flocks are precipitated. This brown body is in- 

 soluble in water, alcohol and aether, soluble in caustic and 

 carbonated alkalies, these solutions form brown precipitates in 

 silver, lead, baryta, and lime salts; the compounds thus ob- 

 tained have no determinate composition. The probable com- 

 position of the brown body appears to be C 12 H 6 N 2 O s . By 

 the formation of this brown substance, formic and hydrocy- 

 anic acids are also probably produced. 



Nitronaphthalic Acid. — Is formed in very small quantities 

 under peculiar circumstances. It is generally mixed in its 

 solution with a small quantity of a resin, from which it may 

 be separated by evaporating to dryness and treating with a 

 little cold water; the little nitric acid which remains suffices 

 to dissolve the resin, and nitronaphthalic acid is left behind as 

 a yellow crystalline powder. May be purified by re-solution 

 in water or aether,' and crystallization. The resin thus sepa- 

 rated still contains nitronaphthalic acid. This acid is soluble 

 in boiling water, and more so in alcohol and aether ; does not 

 contain water. Formula, C 16 H 10 N 2 O 12 . This is the crystal- 

 lized acid ; in the baryta and silver salts two atoms of water 

 are replaced by two atoms of base. The formula of the silver 

 salt is, therefore, O H 6 N 2 O 10 + 2 Ag O. The ammonia 

 salt is easily soluble in water, and tolerably so in alcohol ; 

 the silver salt is white and insoluble. The ammonia salt and 

 acetate of lead give a basic lead salt, which is a yellowish 

 white insoluble powder, O H G N 2 10 + 4 Pb O. The ba- 

 ryta salt is yellowish white, insoluble, contains no water. The 

 nitronaphthalic acid is, therefore, evidently a bibasic acid. Ni- 

 tronaphthalate of lead seems to form, under the action of sul- 

 phuretted hydrogen, another acid, which M. de Marignac 

 intends at a future period to examine. 



In a second paper M. de Marignac states, that by the ac-. 

 tion of nitric acid on hydrochlorate of chloronaphthalese, 

 O H 16 Cl 8 , he obtained an acid and a volatile fluid. The 

 acid did not agree at all with Laurent's naphthalic acid. The 

 fluid product passes over into the receiver with the nitric acid, 

 and separates from it on account of its greater specific gravity; 



