364 



of baryta and 1 of sulphate of baryta, SO 4 Ba 2 , would be produced. 



Now we have 



S0 4 Ba 2 O 



233-2 : 16 :: 100 : 6'86. 



In the actual experiment 1*776 gr. of sulphate of baryta was 

 obtained, and 0'1225 of oxygen evolved. 



1776 : 0-1225 :: 100 : 6-39. 



It has not yet been in my power to pursue further the study of 

 these substances. I may, however, observe, that the peroxide of 

 acetyl contains the elements of carbonic acid and of the acetate of 

 methyl, and the peroxide of benzoyl the elements of carbonic acid 

 and of the benzoate of phenyl. I have ascertained that the peroxide 

 of benzoyl, when carefully heated, loses exactly one equivalent of car- 

 bonic acid ; but the substance formed, although isomeric with the 

 benzoate of phenyl, has not the properties of that body. It is a 

 yellow resin, soluble in ether and alkalies, from which latter solution 

 it is precipitated by acids. 



The existence of a hydrated peroxide may be anticipated, inter- 

 mediate between the organic peroxide and the peroxide of hydrogen, 

 in the same sense as the organic acid is intermediate between water 

 and the anhydrous acid. This substance in the series of benzoyl 

 would be isomeric with salicylic acid. My efforts, however, to pro- 

 cure these bodies have, as yet, been unsuccessful ; and it is to be re- 

 membered that we have no evidence of the existence of a hydrated 

 peroxide of barium, or of any other metal, corresponding to the 

 hydrated protoxide. In the series of ethyl the diatomic alcohol of 

 of Wurtz (C 2 H 6 O 2 ) is isomeric with the hydrated peroxide. But 

 the true peroxide of ethyl remains yet to be discovered. 



The question naturally arises as to what would be the result of 

 making similar experiments with the chlorides and the anhydrides 

 of the bibasic acids. Now carbonic acid may be regarded as the 

 peroxide of oxalic acid : it is the constant product of the action of 

 oxidizing agents upon that body ; and were we able to procure the 

 unknown anhydride of oxalic acid, it would not be an unreasonable 

 anticipation that with the peroxide of barium it would decompose 

 into oxalate and carbonic acid, thus 



2 C 2 3 + Ba 2 O 2 =C 2 O 4 Ba 2 + 2CO 2 . 



