CIIKMISTRY. 



109 



by alcoholic radicals. To obtain 



tin- mrthylanilint' variety of "Paris violet," tlic 



: .lace iii c.intiu't, in n closed ves- 



mpcratuiv, and under prcs-mv, 



aniline ami hvdrnchlorate of aniline; andtoob- 



diiuothylaniline, they subject to the same 



ions iiu-thylanilino and hydrocblorate of 



ne. 



The specimens exhibited by the Fuchsine com- 

 ACIV dc-cribcd as magnificent, especially 

 tlu-ir sphere of radiating crystals, sharp and vo- 

 luminous, of chlorhydrate of rosaniline, along 

 with all tin 1 rosaniline salts. Their principal 

 rival in that article was M. Muller, of Basle, 

 who exhibited rosaniline that was nearly col- 



Messrg. Coblentz Brothers displayed a re- 

 markable series of pure and crystallized color- 

 ing matters derived from coal-tar. Among 

 articles was an enormous block of nitro- 

 toluol admirably crystallized, of a pale-yellow 

 color, and nearly free from nitrobenzol. They 

 have discovered a very cheap process of trans- 

 forming nilrobeuzol into aniline, and nitrotoluol 

 into toluidine. They take cast-iron turnings, 

 roughly ground to powder, and cover them with 

 a layer of metallic copper, by plunging them into 

 a solution of sulphate of copper. These gal- 

 vanized turnings are then placed along with 

 nearly an equal quantity of non-galvanized turn- 

 ings, and surrounded by a sufficient quantity of 

 water. Nitrobenzol, or nitrotoluol, is added, 

 and a galvanic action takes place in the liquid. 

 The water is decomposed, and the nitrogen 

 makes the nitrate body pass into the state of 

 aniline or toluidine, which is then rectified and 

 rendered pure. By treating the residues with 

 sulphuric acid, the copper is dissolved, and can 

 serve for another operation. 



M. KusM)o, of Paris, also had on exhibition 

 some very fine aniline greens and reds obtained 

 by carbohumic acid. The splendid specimen 

 of crystallized and almost white rosaniline, man- 

 ufactured by M. Jean Rod, attracted much at- 

 tention. He produces daily one hundred and 

 seventy-five kilogrammes of muriate of rosani- 

 line, aniline blues, violets, and greens. He man- 

 ufactiires, with the same substances, hydrate of 

 iribnophenylic rosaniline, giving a reddish-violet 

 tint ; hydrochlorate of diphenylic (blue violet) ; 

 and hydrochlorate of triphenylic (blue dye). He 

 also exhibited a cup of five hundred grammes 

 (one and one-eighth pounds avoirdupois) of cy- 

 anide or quinoline blue. This he colls Parma or 

 Alexandria violet, in the preparation of which 

 ethyl replaces phenyl. 



JVVw Products of Coal-Tar. Berthelot has 

 discovered in coal-tar various hydrocarbons, 

 which had not hitherto been observed in that 

 liquid, as well as several wholly new substances 

 of -Treat interest. Of the former class the au- 

 thor mentions styrolene, C 18 H 8 , first in order, 

 a< one of the bodies obtained by the transfor- 

 mation of acetylene. The existence of cyinene, 

 C'joIIi,. in coal-tar had been observed by several 

 chemists ; the liquid boiling at 166 0., proving 



to be cumolcne, C,JI,,. Cymene boils at about 

 180 C., and exhibits the ordinary reactions of 

 the benzole series. When heat- -d to 280 0., 

 with eighty parts of saturated solution of iodhy- 

 dric acid, cymene yields hydruret of decylene, 

 < II.,, which boils between 155 and 160 C. 

 The author has also found in coal-tar two hy- 

 drurets of naphtaline, C M II 10 , and C,,II W ; a hy- 

 druret of acennphtene, C M 1I 1S , which is a liquid 

 boiling at 260 C., and a hydruret of anthra- 

 cene, which is also liquid, and boils at 285 C. 

 Fluorene is the name given by the author to a 

 new hydrocarbon, which separates in the dis- 

 tillation of the heavy oils. It is a white, crys- 

 talline substance, which exhibits a magnificent 

 violet fluorescence, and possesses a sweetish and 

 irritating odor. It fuses at 113, and melts at 

 805, and is very soluble in boiling alcohol. 

 The solution of this body in sulphuric acid is 

 colorless, but the least trace of nitrous acid col- 

 ors it green, and more nitrous acid gives a vio- 

 let color. Fluorene gives a red crystalline 

 compound with picric acid. (American Journal 

 of Science, November.) 



Gun- Cotton and other Explosive Compounds. 

 At the April meeting of the Royal Society 

 Mr. Abel presented a paper on the stability of 

 gun-cotton, in which is given the fruit of the 

 latest investigations of that important question. 

 The following is a brief summary of his conclu- 

 sions : 



1. Gun-cotton, produced from properly puri- 

 fied cotton, according to the directions given 

 by Von Lenk, may be exposed to diffused day- 

 light either in the open air or in closed vessels 

 for long periods without undergoing any 

 change. The preservation of the material for 

 three years under those conditions has been 

 perfect. 



2. The introduction into the finished gun- 

 cotton of 1 per cent, of sodic carbonate affords 

 to the material the power of resisting any 

 serious change, even when exposed to such ele- 

 vated temperatures as would induce some decom- 

 position in the perfectly pure cellulose products. 

 That proportion affords, therefore, security to 

 gun-cotton against any destructive effects of the 

 highest temperatures to which it is likely to be 

 exposed, even under very exceptional climatic 

 conditions. The only influences which the addi- 

 tion of that amount of carbonate to gun-cotton 

 might exert upon its explosive properties would 

 consist in a trifling addition to the small 

 amount of smoke attending its combustion, and 

 in a slight retardation of its explosion, neither 

 of which could be regarded as results detri- 

 mental to the probable value of the material. 



3. "Water acts as a most perfect protection to 

 gun-cotton (except when it is exposed for long 

 periods to sunlight), even under extremely 

 severe conditions of exposure to heat. An at- 

 mosphere saturated with aqueous vapor suffices 

 to protect it from change at elevated tempera- 

 tures, and wet or damp gun-cotton may be ex- 

 posed for long periods in confined spaces to 

 100 0. without sustaining any change. 



