165 



Disulphometholic acid C 2 H 4 S 4 O 12 . 



Disulphetholic acid C 4 H 6 S 4 O 12 . 



Disulphopropiolic acid C 6 H g S 4 O 12 . 



Disulphobenzolic acid C 12 H 6 S 4 O 12 . 



Disulphanilic acid C 12 H 7 N S 4 O 12 . 



Our experiments point out, moreover, the universal occurrence, 

 and the general mode of formation of these substances. All organic 

 molecules, particularly in the nascent state, appear to be capable of 

 assimilating the elements of either two or four equivalents of anhy- 

 drous acid. 



The formation of the two groups of acids which are thus produced 

 presents a great analogy with the production of the nitro-substitutes 

 generated under the influence of nitric acid. All these compounds 

 are generated with the elimination of water. In the action of nitric 

 and sulphuric acid upon benzol, for instance, we have, 



C 13 H 6 + HNO fi =C 12 H 5 N0 4 +2HO 



Benzol. Nitrobenzol. 



C 12 H 6 + 2HNO fi =C 12 H 4 N 2 8 + 4HO 



Benzol. Dinitrobenzol. 



C 12 H 6 + H 2 S 2 8 =C 12 H 6 S 2 6 +2HO 

 Benzol. 



C 12 H 6 + 2H 2 S 2 8 =C 12 H 6 S 4 12 +4HO 

 Benzol. 



The analogy of these reactions is obvious. 



The action of nitric acid upon organic bodies is by no means 

 limited to the production of nitro-compounds corresponding to 

 nitrobenzol and dinitrobenzol ; frequently additional substitutes are 

 formed with elimination of six, eight, and in a few isolated cases, 

 even of ten equivalents of water. It is possible that analogous 

 sulpho-compounds may exist. Hitherto, however, no substances 

 have been observed in which the assimilation of sulphuric acid has 

 gone further than in the disulpho-acids. 



