Cbtalytic Phanomena with AUoiropy, 257 



o 



water is ^irectly decomposed into H and 0, oxide of lead into 

 Pb aud 0, &c. But since I have already fully discussed this 

 subject elsewhere (see my paper "On the chemical actions of Elec- 

 tricity " in the Verhandlungen der Naturforschenden Gesellschaft 

 von Basel), I will not enter upon it further here, aud will only 

 remark that there is no reason to consider as impossible the ex- 

 istence of substances ^possessing the property of changing the 

 of a compound into O, and thereby effecting its catalysis. 



I have still to speak of a class of chemical phsenomena whicli 

 are to be counted among the actions of contact, and form as it 

 were the counterpart to the catalytic pheenomena of which we 

 have hitherto spoken ; I mean the chemical compounds which 

 are formed under the influence of contact of many substances. 



With this class of phsenomena it must also be noticed, that 

 most, if not all of them, relate to oxygen, that is, they consist of 

 oxidations, a circumstance which deserves, in my opinion, the 

 greatest consideration. 



At ordinary temperatures does not form compounds either 

 with any simple body, or with the greater number of oxidizable 

 compound substances ; while under the same circumstances O 

 readily associates itself with most of the elementary substances, 

 and with compound bodies capable of receiving more oxygen. 

 From these and other reasons which have been elsewhere ex- 

 plained, I have arrived at the opinion that 0, as such, can be united 

 with no substance ; and that O alone is capable of effecting oxi- 

 dations, whether enters as such into the compound, or exists 

 in it as 0. As will be readily seen, it would follow from the 

 correctness of^this assumption, that O must always be first 

 changed into O if the oxidation of any substance is to be ac- 

 complished. 



The change of into O may, as my experiments have shown, 

 be effected in various ways ; by imponderable as well as by pon- 

 derable agents. But since the allotropizing influence, which, 

 for instance, electricity exerts upon 0, does not directly concern 

 the subject under discussion, we shall here only treat chiefly of 

 the ozonizing -actions produced by ponderable agents; and we 

 shall first of all speak of phosphorus, which is certainly one of 

 the most remarkable bodies of this kind. 



Common oxygen, as is well known, when placed in contact 

 with phosphorus under appropriate circumstances, acquires the 

 property of oxidizing, at ordinary temperatures, not only plios- 

 phorus itself, but also a large number of simple and compound 

 substances, with which it would not associate itself without the 

 presence of jjhosphorus. Lead aud silver are oxidized by the 

 oxygen so altered to peroxides ; nitrogen (in the ])rcscnce of HO, 

 KO, &c.) to nitric acid ; iodide of potassium is decomposed with 



Fhil, Mag. S. 4. Vol. 13. No. 80. April 1857. T 



