Dr. Wollaston on the Discovery of Palladium. 325 
sulphate of iron, by muriate of tin, by prussiate of potash, by 
each of the pure alkalis, and by hydrosulphurets. 
The precipitate obtained in each case was also found to be 
reducible by mere heat to a white metal, that, except in very 
small quantities, could not be fused alone by the blowpipe, but 
could very readily be fused with sulphur, with arsenic, or 
with phosphorus, and in all other respects resembled the 
original metal. 
The only hypothesis, on which I thought it possible that I 
could be deceived, arose from the recollection of the error, 
which subsisted for a few years, respecting the compound 
formerly called siderite. It was possible that some metallic or 
other fixed acid might unite too intimately with either a known 
or an unknown metal to be separated by the more common 
simple affinities. I consequently made such attempts as ap- 
peared best calculated to disunite a compound so constituted. 
Having boiled the oxide with pure alkalis, and found it to be 
unaltered, I thought the affinities of lime or lead might be 
more likely to detect the presence of the phosphoric or of any 
known metallic acid ; and accordingly I made various attempts 
by muriate and nitrate of lime, as well as by nitrate of lead, to 
effect a decomposition of the supposed compound. In the ex- 
periment on which I placed the greatest reliance, I poured 
liquid muriate of lime into a solution of palladium in nitro- 
muriatic acid, and evaporated the mixture to dryness, intending 
thereby to expel any excess of acid that might have been left 
in the solution, and to render either phosphate of lime, or any 
compound of lime with a metallic acid, insoluble in water. The 
residuum however was very readily dissolved by water, and 
