1863.] 657 



barium, and in the case of camphoric acid, giving with acetate of 

 lead a precipitate of camphorate of lead. These solutions are in a 

 state of continual decomposition. Only in one instance, that of cam- 

 phoric acid, was it found possible to analyse the substance, and that 

 only by indirect processes. The oxygen contained in the organic 

 peroxide was estimated in a measured portion of the solution by means 

 of a standard solution of iodine ; the camphoric acid formed on 

 boiling was determined by precipitation with acetate of lead in another 

 measured portion ; and in a third portion the barium was estimated 

 as sulphate. The results of these determinations are given below, 

 the camphoric acid being assumed as correct. They lead to the 

 conclusion that the solution contains the elements of one equivalent 

 of anhydrous camphoric acid, one of oxygen, and one of baryta. 



Atomic weight. Calculated ratio. Found. 



C 10 H 14 O 3 182 25-12 25-12 



O 16 2-20 2-07 



Ba 2 O 153 21-12 21-51 



the reaction being 



C 10 H 14 3 + Ba 2 2 =C 10 H u 5 Ba 2 . 



That the substance formed is to be regarded as the baryta salt of the 

 peroxide of camphoryl, and not as the camphorate of the peroxide of 

 barium, is proved by the reactions of the solution, which does not 

 give peroxide of hydrogen when decomposed by acids, or a precipitate 

 of the hydrated peroxide of barium when heated with a solution of 

 baryta. 



The organic peroxides constitute a new and peculiar group of 

 chemical substances characterized by reactions never hitherto found 

 in any compound of carbon, and which materially extend our views 

 of the possible properties of the so-called organic combinations, and 

 of their analogies to inorganic substances. They are the organic 

 representatives of chlorine in the same sense as the oxides of the 

 compound ammoniums are the representatives of potash, and in a 

 yet closer sense than ether and alcohol resemble the oxide and its 

 hydrate, or than ethyl or marsh-gas are analogous to hydrogen. 

 This analogy is of a profound character, not consisting merely in 

 the analogy of symbolic form, but in the absolute identity of reactions. 



