458 GOLD, PLATINUM, PALLADIUM, & c . 



acid is very nearly correct ; but the platinum is 

 too much, while the oxygen is as much too little, 

 as if the metal had not been completely reduced 

 to the metallic state. 



5 * * tr * ec * to P re P are a quantity of peroxide of 

 platinum by the process pointed out by Berze- 

 lius. Finding it to contain both muriatic acid 

 and an alkali, I reduced it to a fine powder, and 

 boiled it for a week in a flask kept nearly full of 

 distilled water. After this treatment, the pro- 

 portion of salt which it contained was so exceed- 

 ingly small, that I am disposed to consider the 

 characters which my powder possessed, as very 

 nearly those of pure peroxide of platinum. Its 

 colour was a brownish black ; it was tasteless, 

 insoluble in nitric, sulphuric, oxalic, and acetic 

 acids ; but it dissolved, though slowly, and 'not 

 without considerable boiling, in muriatic and 

 phosphoric acids. I made no attempt to analyze 

 it, both because it was not absolutely pure, and 

 because I was not sure whether it was perfectly 

 anhydrous. 



Amalgam g. Conceiving that the amalgam of platinum was 

 num. likely to throw some light on its atomic weight, I 

 made a quantity of it by triturating platinum pow- 

 der and mercury in a mortar ; beginning with a 

 few grains of each, and adding additional portions 

 of both metals as the amalgamation proceeded. 

 The fluid amalgam thus formed was put into a 

 leathern bag, and subjected to strong pressure in 



