180 Drs. Muspratt and Hofmann oti Toluidinc. 



lated and peculiar, and therefore till chemists succeed in dis- 

 covering more compounds of the same classes, the formation 

 of basic bodies in this manner must be limited. 



It is quite different with another method, by which chemists 

 have also succeeded of late years in procuring basic bodies. 

 Zinin* was the first who conceived the happy idea of investi- 

 gating the products produced by the action of sulphuret of 

 ammonium upon nitrogenous compounds, which latter were 

 procured by treating various carbo-hydrogens with nitric acid. 

 Zinin investigated in this point of view Laurent's nitro7iaphtha~ 

 lase obtained by the action of nitric acid upon naphthaline, and 

 nitrobenzide, discovered by Mitscherlich, and he arrived at the 

 remarkable result that these bodies lose their whole oxygen 

 under the influence of sulphuretted hydrogen, and in assuming 

 hydrogen pass into combinations, presenting in every respect 

 the characters of true organic bases ; the two bases formed 

 by Zinin in the manner described, are the Jiaphthalidain, for 

 which Berzeliusf has lately proposed the more appropriate 

 name of naphtalidine, and benzidain, afterwards recognised as 

 identical with aniline. The following comparison of formulaj 

 shows how nearly the original compounds are connected with 

 the required products : — 



Nitronaphthalase Cgg H^ NO4 = 

 Naphtalidine . . C20 H9 N = 

 Nitrobenzide . C12 H5 NO4 = 



Anihne . . . C12 H7 N 



By this comparison the transformation occurring through 

 sulphuret of ammonium may be considered as ultimately a 

 substitution of the elements of amidogen for those of peroxide 

 of nitrogen, independently of these combinations existing or 

 not in the compounds. Zinin's discovery is very remarkable 

 in its consequences, and will, without doubt, become of vast 

 importance for the group of alkaloids. If we consider how 

 large is the number of carbo-hydrogens already known, all of 

 which change their composition when acted upon by nitric 

 acid, giving compounds corresponding to nitronaphthalase and 

 nitrobenzide; then, supposing these products to suffer also an 

 analogous decomposition with sulphuret of ammonium, there 

 will be no limit to the production of new bases, and we may 

 naturally infer that even those occurring in nature might be 



* ^nnal. der Chan, unci Pharm., vol. xliv. p. 283. 

 \ Jahresbenchty xxii. p. 545. 



