1 4-t Royal Society : — 



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

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

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



C14H8S4O14. 



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

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

 found to contain 



C,,(HeBa2)S,Oi,+2aq. 



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

 equivalent of aiiisol (the product of the action -of alkaline earths 

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

 hydrous sulphuric acid. J\I. 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 (5 equivalents of oxygen, is 

 ])erfectly similar to that which this agent exerts upon acids with 

 4 equivalents of oxygen. 



Acetic acid. 



1 St Stage . . C , II4 O4 + 211804= C4 H^ S., Oj^ + 2II0. 



2nd Stage. . C^ H4 04+4HS04=C3 H4S;Oi._, + 4IIO + 2C0o. 



Anisic acid. 

 1st Stage C16 H8 06 + 2HS04=Ci6HaS.,0^.,-f 2H0. 

 2nd Stage Cjc H8 0fi + 4HS04=Ci4HgS4 0i4 + 4HO + 2CO,. 



There can be no doubt that salicylic acid, so closely allied to anisic 

 acid, in fact, its homologue, a step lower in the system, must exhibit 

 a similar deportment. Mr. Baldwin Duppa has been occupied with 

 this subject in my laboratory, and has already obtained the first term, 

 the sulpho-salicyl ic acid, 



^14-^6 ^2^12' 



which forms extremely beautiful compounds. 



On submitting salicylic acid to the action of an excess of sul- 

 phuric acid, at a temperature of 180°, the same phenomena present 

 themselves which are noticed in the case of salicylic acid, a powerful 

 evolution of carbonic acid ensues, and the solution now contains a 

 new sulphur-acid, which is crystalline. As yet Mr. Duppa has 

 not succeeded in obtaining this acid in a state of sufficient purity 

 for analysis, but it may be assumed, without much hesitation, that 

 it will be found to be 



Disulphophenic acid .... Cjj 11^, S4 0,4. 



"On the Separation of Iodine, Bromine, and Chlorine, and the 

 comparative degree of Affinity of these Elements for Silver ; with 

 some Analyses of their Combinations with that Metal occurring in 

 Chih." By Frederic Field, Esq. 



Although both bromide and iodide of siher are deconij)osed by 



