138 The Literature of Ozone. 



gators from the great labor of repeating bis work, Dr. Bolton 

 completed this Index, and published it in the Annals of the N. 

 Y. Academy of Sciences, or as the society was then called, the 

 N". Y. Lyceum of Natural History, Vol. IX, February, 1870.. 

 This first publication was followed by a second (idem, XI, Nov., 

 1875), in which Dr. Bolton has given in the compass of 44 finely 

 printed octavo pages, an " Index to the Literature of Manga, 

 nese," beginning as far back as the year 1596, and brought down 

 through nearly three centuries, to the year 1874. 



His labors prompted Prof. E. J. Hallock to continue the work 

 by preparing an "Index to the Literature of Titanium,'' (1783- 

 1*876,) published in Ann. K Y. Acad. Sci., Vol. I, p. 53, Dec. 

 1876, and Prof. G. J. Rockwell, a similar " Index to the Litera- 

 ture of Vanadium" (1801-1876), idem, Vol.1, p. 133. Since 

 the publication of the two indices by the author, the Academy 

 has also published an "Index to the Literature of Electrolysis," 

 idem, Vol. II, p. 313, by Mr. W. W. Webb. 



The third portion of the author's preceding memoir was an 

 essay upon " The History of Antozone and Peroxide of Hydro- 

 gen." It pointed out the fallacy of the arguments and proofs 

 offered by Schonbein and Meissner, for the existence of the so- 

 called Antozone, and described the experiments of Von Babo, 

 Nasse, Engler, and others, by which the certainty of the non-exist- 

 ence of Antozone had been demonstrated. The essay furthermore 

 gave some account of the artificial sources of Peroxide of Hydro- 

 gen, and of the experiments devoted to a demonstration of its 

 probable occurrence in nature. This was followed by a fourth 

 part, devoted to an "Index to the Literature of Peroxide of Hy- 

 drogen " (1818-1878), similar in plan to that upon ozone. 



In returning to this subject, it is with the hope of assisting 

 fellow-students in two ways. First, by bringing these indices 

 down to date, which will make the preceding work of much 

 greater utility. Secondly, by pointing out the uselessness of re- 

 peating, as is being constantly done, the investigation of matters 

 previously studied with thoroughness, and of overlooking other 

 topics which are at present incompletely understood. 



I. Sources and Preparation of Ozoxe. 

 The formation of ozone is to be looked for in all cases where 



