495 



Anisic acid, treated with Nordhausen sulphuric acid, at a tem- 

 perature of 100, assimilates the elements of 2 equivs. of sulphuric 

 acid, and is converted into a crystalline acid, containing 



The formula of this acid, which M. Zervas calls sulphanisic acid, 

 was controlled by the analysis of a crystalline lead-salt and a barium 

 compound, which were found to contain respectively 



Lead-salt .... C 16 (H 6 Pb 2 ) O 12 + 2aq. 

 Barium-salt . . C 16 (H 6 Ba 2 ) O 12 + 2aq. 



If the mixture of anisic and fuming sulphuric acid be submitted 

 to higher temperatures than that of boiling-water, a lively evolution 

 of carbonic acid takes place, containing, if the temperature be main- 

 tained within the proper limits, scarcely a trace of sulphurous acid. 

 After several hours' digestion, the solution contains no longer anisic 

 or sulphanisic acid, but a new acid, which has the composition 



^14 ^8 ^4 OH- 



The formula of this acid, which could not be obtained in a state 

 fit for analysis, was fixed by the analysis of a barium-salt, which was 

 found to contain 



C 14 (H 6 Ba 2 )S 4 14 +2a q . 



This acid may be considered as formed by the association of 1 

 equivalent of anisol (the product of the action of alkaline earths 

 upon anisic acid at a high temperature) with 4 equivalents of an- 

 hydrous sulphuric acid. M. Zervas has, in fact, experimentally 

 proved, that his acid may be obtained directly by treating anisol 

 with fuming sulphuric acid, and he accordingly proposes to designate 

 this compound by the name of disulphanisolic acid. 



From the preceding experiments it is obvious that the action of 

 sulphuric acid upon organic acids with 6 equivalents of oxygen, is 

 perfectly similar to that which this agent exerts upon acids with 

 4 equivalents of oxygen. 



Acetic acid. 



1 st Stage . . C 4 H 4 O 4 + 2HSO 4 = C 4 H 4 S 2 O 10 + 2HO. 

 2nd Stage.. C 4 H 4 O 4 + 4HSO 4 =C 2 H 4 S 4 O 12 



