408 CLOUD, ON PALLADIUM FOUND IN GOLD. 



mains much doubt with respect to the existence of such a sim- 

 ple substance. Professor Murray, one of the latest writers on 

 chemistry, in speaking of palladium, and other metals found 

 in combination with crude platinum, says; "It is not impossi- 

 ble that they may be alloys of others; or that the peculiar pro- 

 perties which they appear to exhibit, may arise from combina- 

 tions which analysis has not detected. The peculiarity of their 

 association in one natural production, while there are no traces 

 of them in any other, perhaps lends force to this supposition." 

 It has been my fortune, however, to obtain it from a different 

 source; which enables me to point out some of its characters, 

 that will throw such light on the subject, as to remove all doubts 

 respecting the existence of this simple metal. 



On the 15th of May, 1807, a deposit of gold bullion, from 

 Brazil, in South America, was made at the Mint of the United 

 States, weighing 797 ounces, 4 dwts., gross, equal to 819 oz. 

 11 dwts. llgrs. standard. It was composed of about 120 small 

 ingots, differing in weight; each of them was stamped on one 

 side with the arms of Portugal, and the inscription of " Rio das 

 Mortes." The other side was stamped with a globe. They were 

 also marked with their respective qualities. Among them were 

 two or three ingots, so remarkably different in coiour from any 

 of the common native alloys of gold, that I was induced to 

 reserve one, weighing 3 ounces, 11 dwts. 12 grains, for exa- 

 mination, and which was subjected to the following experi- 

 ments. 



Experiment 1st. A portion of the reserved bar was examined 

 for silver, by solution in the nitro-muriatic acid ; but no trace 

 of that metal was indicated. 



Exp. 2d. 24 carats of this bar were combined with 48 carats 

 of fine silver, and cupeled with pure lead, for the purpose of 

 destroying any of the base metals that might be in combina- 

 tion; but there was no loss of weight produced: consequently, 

 there were none of the easily-oxidable metals in the compound. 

 Exp. 3d. The pure metals from experiment 2d were redu- 

 ced to a thin lamina by rollers, and subjected to the action of 

 pure nitric acid : the silver, together with the native alluy of 

 the gold, were dissolved by the acid, which was tinged of a 



