146 The Literature of Ozone, etc. . 



oxygen has been noted lias been largely increased. Thus Hoppe- 

 Seyler has pointed out that is formed when palladium-hydrogen 

 is shaken up in contact with water and air (Berl. Berichte, XII, 

 1551). Under these circumstances he noted the formation of 

 the third by-product, ammonium nitrite, as well. The author, 

 prompted by theoretical considerations, sought for the presence 

 of ozone and hydrogen peroxide, since according to the hypothe- 

 sis above enunciated, both should be present. Ozone he failed 

 to detect, hydrogen peroxide was found in quantity large enough 

 to admit of its quantitative estimation (Berl. Berichte, XIV, 

 976). So also, palladium, platinum, and other so-called "car- 

 riers of oxygen," owe the energetic oxidizing actions which occur 

 in their presence, and which were formerly spoken of as '"cata- 

 lytic," to their power of eifecting a separation of the oxygen 

 molecule into its constituent atoms. This is shown by the ex- 

 periments of Traube and Baumann, who found that palladium 

 will cause the oxidation of carbon monoxide to dioxide in pre- 

 sence of hydrogen peroxide, whilst without palladium no such 

 oxidation occurs. It has been likewise noted by the author that 

 platinum black, when shaken up in a bottle partly filled with 

 air along with a solution of indigo, turns the latter yellow by 

 causing its oxidation and the formation of isatin. Since this 

 very powerful oxidizing action is not produced by oxygen in its 

 ordinary condition, it may be ascribed to the atomation of the 

 oxygen under the influence of the platinum black. 



The number of observed Cases of the formation of atomic oxy- 

 gen has been largely increased by the recent researches of Rad- 

 ziszewski on the Phosphorescence of Organic Bodies. He di- 

 vides such phosphorescent organic bodies into two groups : 1st. 

 Those which phosphoresce when the atomic oxygen which they 

 already contain, and which lias been previously formed under 

 the influence of some activating agent like sunlight, operates 

 upon the organic body, on the addition of an alkali. 2d. Those 

 bodies which, on the addition of an alkali, themselves form 

 atomic oxygen, and by combining with this atomic oxygen, be- 

 come phosphorescent. To the first group belong various hydro- 

 carbons, especially the aromatic, the terpen es, etc. To the sec- 

 ond, belong more especially the aldehydes, or such bodies as 

 when treated with an alkali, form aldehydes. To the latter sub- 



