1826.} On the Vapours which rendef Platinum red-hot. 2f 



and hydrogen gases from the ether more rapidly than the platinum. 

 Hence a superabundance of carbon remained which was precipi- 

 tated on the inferior surface of the palladium. 



This opinion may be seen by reference to Felix Farley's 

 Bristol Journal for Aug. 28, 1824, in the report of the above 

 Society's proceedings during that week. 



But about the latter end of September, having repeated the 

 experiment frequently in the interim, I found that the slip of 

 palladium had sensibly decreased in size and weight, and having 

 collected a small quantity of this black substance, and dissolved 

 it in nitric acid, with the assistance of heat, a black residue 

 remained, which floated on the acid solution. By its deflagra- 

 ting with nitre, 1 considered it to be carbonaceous matter. 



The nitric solution was of a reddish-brown colour, and it 

 contained palladium ; for it precipitated olive-brown with 

 ferrocyanate of potash; orange with chloride of tin. Iron reduced 

 it to the metallic state. 



It was then very evident from all these facts that the palla- 

 dium had combined with the oxygen of the air or ether, while it 

 effected the combination of the two gases, and was converted 

 into an oxide at a red heat — a circumstance which has not, I 

 believe, been before noticed. 



Its colour, when freed from the carbon it contained, seemed 

 to be of a blackish-brown tinge. 



As I did not possess any considerable quantity of palladium, it 

 was impossible for me to ascertain the proportion of oxygen 

 contained in this oxide. 



Article V. 



Addition to the List of Substances that cause a Coil of Platinum 

 Wire to continue in a State of Incandescence (having previousli/ 

 been heated to Redness) when held over the Vapour, arisina- 

 from their Evaporation, By H. B. Miller, Esq. 



(To the Editors of the Annals of Phi losophi/.) 



GENTLE MEN, Bristol, May 11,1 826. 



The substances discovered by Sir H. Davy, and known to 

 produce this effect, were, I believe, the following : 



Camphor, Sulphuric ether. 



Alcohol, Phosphorized ether, 



- Spirits of wine. Nitrous ether. 



By a numerous series of experiments which I made in 1824, 

 and which I communicated to the members of the Bristol Insti- 

 tution at a meeting of their Philosophical Society, the following 

 substances also produced a similar effect, °. 



