SCIE?<TIFIC NEWS. 7/ 



Sulpliur injlamed hy oxide of lead. 



"Dr. THOMSON'S paper on th^ oxides of lead, Jounml, Brown oxide 

 \ o\. VIII, p, 280, having been translated into French, and ^ulp}iur\ri^^ 

 userted in the Annales de Chimie, the passage in which he turaiion v/itk 

 ays he did not succeed, in triturating sulphur with the ^^ 

 rown oxide, p. 283, is thus commented upon. 

 ** Nothing however is more certain, than that Mr. Vau- 

 quehn has inflamed sulphur by triturating it with brown ox- 

 ide of lead, as he formerly mentioned. He lately repeated 

 •this experiment, in one of his lectures, before upwards of 

 fifty persons, among whom was prof. Proust of Madrid. 

 The only precautious the experiment requires are, to boii j^t^j.^^;,^ ™g^ 

 the nitric acid a long time on the brown oxide, that no mi- cd-ntiuntu 

 Ilium may remain among it; to wash it afterward with a, 

 great deal of boiling water, so as to take up all t.lie nitrate 

 of lead; and lastly, to dry it well, aud to triturate it widi 

 flowers of sulphur equally well dried. 



" On observing these essential conditions, there can be no 

 doubt, but Y)r. Thomson Avill succeed in inflaming the sul- 

 phur. The supposition he makes, to account for the plie- 

 nomeuon, is inadmissible, for Mr. Vauquelin never employ- 

 ed oxigenized muriatic acid, to prepare the brown oxide of 

 lead. 



Yttria and Cerium. 



THE chemists at Upsal at first imagined, that cerium yttnaoxJ**- 

 was nothing but u mixture of barytes, yttria, and magnesia, nizes nimuni* 

 Mr. Eckeberg, desirous of comj^aring them, has found that 

 yttria, after having been a long time exposed to the action 

 of fire, gives out oxigenized muriatic acid, when dissolved in 

 the common muriatic acid. Is yttria, asks Mr. Berzelins, 

 one of the new metals, uranium, titanium, or cerium, with 

 its nature ai it were changed ? 



Mr. Gahn has formed an alloy of cerium with iron, partly AHoy of ce- 

 in a grayish powder. '^"™ ^^'^ ^«°- 



New 



