1867.] Chemistry. 393 



elements, we have oxalic acid built up by the successive combination 

 of its constituent elements. In order to produce oxalic acid in this 

 way, gaseous acetylene is shaken up with a strongly alkaline 

 solution of permanganate of potash, added gradually as long as the 

 solution is decolorized, and taking care to keep the flask cool. When 

 the operation is ended, the solution is filtered from the binoxide of 

 manganese. The oxalic acid will be found in combination with the 

 potash, and may be separated by means known to every chemist. 

 Formic and carbonic acids are produced at the same time as oxalic 

 acid, no doubt, M. Berthelot states, by the splitting up of some 

 nascent oxalic acid. 



Several other hydrocarbons were experimented with in the same 

 way. Ethylene gave the same products as acetylene. Allylene 

 gave malouic, acetic, and carbonic acids. Amylene gave oxalic, and 

 a mixture of several others, probably pyrotartaric, succinic, and 

 malonic acids. Styrolene yielded benzoic and carbonic acids. 



M. Berthelot has also succeeded in forming toluol synthetically. 

 The formula of toluol, C 14 H 8 , indicates the addition of marsh gas 

 to benzol with the elimination of two atoms of hydrogen. 



C U H 8 = C 2 H 4 + C 12 H 6 — 2 H. 



Toluol. Marsh Gas. Benzol. 



The excessive heat required to effect the direct combination of these 

 bodies was fatal to the existence of toluol, and a product of its 

 condensation, anthracene, was obtained. By bringing them together 

 in the nascent state, however, the desired combination was effected, 

 and toluene formed. This was done by submitting a mixture of 

 acetate and benzoate of soda and lime to distillation. Besides 

 toluol some other hydrocarbons were produced, which M. Berthelot 

 regards as higher homologues of toluol. 



An important paper " On new Hydrocarbons obtained synthe- 

 tically" has been published by Fittig & Bigot. For this we must 

 refer the reader to the original, or the translation indicated below.* 



The researches of Mr. P. Griess " On a new Series of Organic 

 Compounds, in which Hydrogen is replaced by Nitrogen," have led 

 him to the discovery of a highly explosive series of salts, one of 

 which he proposes as a substitute for fulminating mercury. This 

 is the chromate or chlorochromate of diazobenzol. According to 

 the French patent, it is prepared in the following way: — One 

 equivalent of hydrochlorate of aniline is mixed with two equivalents 

 of hydrochloric acid, and to these one equivalent of nitrite of soda 

 in strong solution is very gradually added. The mixture is left to 

 itself so long as any nitrogen is disengaged. In this way diazo- 

 benzol is produced. To precipitate the salt named above, a con- 

 centrated solution of one equivalent of bichromate of potash in one 



* ' Ann. der Chem. u. Pharui.' Bd. cxli., p. 160. ; The Laboratory,' vol. i., p. 121. 

 VOL. IV. 2 D 



