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SCIENTIFIC NEWS. 



numerous as almoft entirely to remove this doubt, or to con- 

 vince him that palladium was really a fimple fubftance ; as 

 its concealed author pretended, and not an impofition upon 

 the public, as Mr. Chenevix has now proved it to be. 

 It is platina and It appears then, from Mr. Chenevix's experiments, that 

 mercury. ^Js pretended fimple metal is a combination of platina and 



mercury; and it mtift excite not only aftonifhment, but humi- 

 lity in the cultivation of natural knowledge, to find that a 

 combination of two metals, each upon fo high a fpecific gravity 

 as thole which are combined in palladium, fliould produce a 

 compound, the fpecific gravity of which is lefs than that of the 

 leaft weight of the component fubftances ; and, moreover, 

 that mercury whofe affinity for caloric had hitherto been 

 found to baffle all attempts to deftroy its volatility ; could, 

 when combined with platina, become as fixed as any metallic 

 fubftance, with which we are acquainted. But nature laughs 

 at our theories, and forces us from time to time, by extraordi- 

 nary difcoveries of this fort, to acknowledge that we are her 

 vaflals, and that we drive in vain to bring her within our 

 laws. 

 Procefs for com- Without entering into any detail of the contents of this 

 pofing it. paper, which is interesting in many other refpects, as well 



as in the difcoveries which it announces, we fhall fliortly 

 ftate one of the means, feveral being given, by which 

 Mr. Chenevix accomplishes the production of palladium ; 

 or, at leaft, of a fubftance having every chemical or phyfical 

 property of that fuppofed metal. He diflblves platina, pro- 

 cured from the ammoniacal fait, in nitro muriatic acid. To 

 this he adds twice its weight, at leaft, of red oxide of 

 mercury, but if the acid be not faturated he adds more till the 

 whole liquor is perfectly neutralized. This combination of 

 muriate of platina and mercury, is then to be poured into a 

 folution of green fulphate of iron, and the black metallic 

 precipitate which is thereby formed is, when collected, and 

 the excefs of mercury driven off, at a red heat, fufed in a 

 Black's furnace. It melts into a metallic button at a white heat, 

 and becomes palladium ; a compound as it feems, of two 

 parts of platina to one of mercury. 

 Variations in Mr. Chenevix finds it difficult always to combine with 



ccompoun . pj at j na ^g f ame q Uan tity f mercury; and the fpecific gravity 

 of his palladium varies like that which is fold by Mrs. Fofter ; 

 4 but 



