240 THE DISCOVERY OF NEW ELEMENTS. 



Cerium, lanthanum, and didymium have recently been the objects of 

 attentive researches having in view a practical end — the construction 

 of mantles used in incandescent gaslights. It had been for some time 

 suspected that didymium was not a simple body, but it was Carl Auer 

 von Welsbach,' the inventor of this method of illumination, who has 

 the honor of having succeeded, in 1885, in separating didymium into 

 its two elements, praseodymium and neodymium. By the use of mona- 

 zite, as was shown at the Chicago Exposition in 1893, a greater quantity 

 of the salts of these remarkable metals was prepared and the practical 

 application of them assured. 



The existence of metacerium announced by M. Brauner^ does not 

 appear as yet absolutely established, neither does that of russium^ 

 which M. Chruschtschow found associated with thorium in certain 

 zirconiums and in monazite, and whose atomic weight is said to be 220. 

 The jargonium of Sorby,^ the austrium of Linnemann,^ as well as the 

 norvegium of Dahll," the actinium of Phipson," theidumium of Websky,^ 

 the masrium of Richmond and Off,^ and an unknown element which 

 M. K. J. Bayer thought he had found in French bauxite have vanished 

 into the void. 



We will also mention, as curiosities, kosmium and neokosmium, that 

 take their names, not from the kosmos but from Kosmanu,"' who, on 

 the 16th of November, 1896, took out a patent for the preparation of 

 their oxides. If it were not for the expense of the patent, it might 

 have been thought a pleasantry, like that perpetrated a few years ago 

 by the Chemiker Zeitung,'^ that told its readers over the signature of 

 M. Fried. Much, the marvellous history of the discovery of damarium. 



The world of chemical processes is like the stage of a theatre on 

 which are exhibited the details of the action of the play, but in this 

 world the characters are represented by elements, each of which plays 

 its part, whether it be a silent or a speaking one. Among the latter 

 may be classed two elements discovered during the last twenty-five 

 years — gallium and germanium. 



Gallium was discovered on the 27th of August, 1875, by Lecoq de 

 Boisbaudran,'^ in the blende of Pierrefitte, by means of two quite well- 

 j narked lines that appeared in the violet portion of that spectrum of 

 that blende, which, however, as was afterwards shown, contains but a 



' Carl Auer von Welsbach, Monatscli. flir Cliemie, 6. 

 2B. Brauuer, Chem. News, 71. 

 •■'K. D. Chruschtschow, Chem. Zeitung, 1890. 

 ''Sorby, Berichte der deiitschen Cliem. Ge8ellsch.,2. 

 ^E. Linuemann, Monatsch. f. Cheraie, 7. 

 sTellef Dahll, Berichte d. deut. Chem. Gesellsch., 12 et 13. 

 7T. L. Phipsoii, ibid., 14 et 15. 



8M. Websky, Sitzungsber. d. Akad. d. Wisseusch. zii Berlin, 30. 

 9H. D. Eichmond and Ofif, Chem. Zeitung, 1892. 

 loKosmaun, Zeitsch. f. Elektrochemie, 1896-97. 

 '1 Chem. Zeitung, 1890. 

 '^Lecoq de Boisbaudran, Comptes rcudus, 81. 



