110 APPENDIX 



unite with the oxylized oxygen of the former to form the 

 peroxide, whereas another portion of the lead oxide 

 combines with murium oxide to form lead chloride. 

 Hydrochloric acid, in contact with concentrated nitric 

 acid takes up 6 from N0 4 + fi6, being oxidized to Mu6, 

 and this most probably unites with N0 4 to form an 

 unstable compound, which constitutes the oxidizing agent 

 in aqua regia. The action of murium oxide on N0 2 4- A 6 

 differs only in that the evolution of chlorine takes place 

 with greater ease. When electric sparks are passed 

 through a mixture of gaseous hydrochloric acid and oxygen, 

 chlorine and water are produced, as is well known. 

 According to my observations electricity determines the 

 combination of murium oxide with oxygen, and the latter, 

 by uniting with the oxide, is transformed into the oxylized 

 state. When a mixture of water vapour and oxygen gas 

 is subjected to the same electrical treatment, a hydrogen 

 peroxide is formed, namely ozone, and if the oxides of 

 lead, manganese, silver, etc., were capable of existing in 

 the gaseous form they would, when mixed with oxygen, 

 undoubtedly be transformed into their peroxides 011 

 passing electric sparks through them. Lead hydroxide 

 held before a point from which electricity is escaping into 

 moist oxygen or atmospheric air is, it is true, according to 

 my experiments, changed into its peroxide ; this is, how- 

 ever, due to a secondary reaction produced by the ozone 

 which is formed under these circumstances. 



With regard to the chemical nature of ozone, the 

 highest authority on chemical questions now shares the 

 view first brought forward by de la Kive, that ozone is 

 nothing but oxygen modified by electricity, and that it 

 does not contain hydrogen. These chemists support their 

 view by the fact that electric sparks passed through 



