I'Sli.] On the Caxise of Chemical Proportiom, - S5 



oxide of this metal, and its soluble muriate is decomposed without 

 producing any other muriate. If we bum palladium filings in a 

 platinum crucible along with caustic potash and a little saltpetre, 

 the palladium is oxidated. We obtain a chesnut coloured oxide, 

 W'hicli contains potash, but which dissolves in muriatic acid without 

 the disengagement of oxymuriatic gas, and forms the common 

 muriate. 1 have found that 100 of palladium combine whh irL'09 

 to form the oxide of palladium. The oxide thus formed bears all 

 the characters of containing more than 1 volume of oxygen. If 

 we suppose it to contain 2, the volume of palladium will weigh 

 1407 5«. 



17. ylrgenlum^ silvpr (Ag). — I have determined the composition 

 of the oxide of silver from the sulphurer, because it was nut pos- 

 sible to iiave so exact a result from the direct analysis of the oxide. 

 I found by this means that 100 silver combine with 7-14 of oxygen. 

 But as we do not know the volume of sulphur with precision, it is 

 possible that the oxygen may amount only to 7'3575. The oxide 

 of silver appears to contain 2 volumes of oxygen. Hence the 

 volume of metal will weigh 2688-17 or 2718-3l'. 



18. Hi/ilrdiiryium, vu-rciirij (Hy). — Mr. Sefstrom has examined 

 with care the composition of the oxides and sulphurets r.f this 

 metal. According to his experiments, 100 of mercury cooib'me to 

 form the red oxide with 7-89, 7'9, or 7-99, of oxygen £rid with 

 half as mucli to form the black oxide. As this last bcLngs to those 

 oxides which I conceive formed of equal volumes of oxygen and 

 metal, the volume of mercury ought to weigh 2531'f). its mini- 

 mum should be 2503"13, and its maximum 25361. 



19. Ctipnnn, copper (Cu). — I have found that 100 copper com- 

 bine witli 2 1'8 or 25 oxvgcn to become black oxide, and with half as 

 much to form the protoxide. If this last be Cu + O, the volume of 

 copper ought to weigh 806 48, or at a minimum 800. 



20. Kiccolum, nickel (Ni). — Messrs. Rolhoff and Tupputi have 

 examined the oxides of this metal, with results agreeing well with 

 each other. Rolhofi" found that a solution of neutral muriate of 

 nickel, which contained 1-88 of oxide of nickel, gave with nitrate 

 of silver 7" 182 of fused muriate of silver; that is to say, that 100 

 muriatic acid neutralize 137'52 of oxide of nickel ; from which it 

 follows that the oxide is composed of 100 metal and 27'255 of 

 oxygen. Some experiments of Kolhoff induced him to beli«ve 

 that the peroxide of this metal contains \\ or 11- as nui(;h oxygen 

 as the ])rotoxide. In the first case the protoKide would l>e Ni + 

 3 O ; in the second case, Ni + 2 O. I consider the last as most 

 probable. Hence the volume of metal should weigh 733"8. 



Buchol/ has rendered it probable that nickel has an oxiiie con- 

 taining less oxygen than either of the preceding. We obtain it 

 V\heu we decompose by means of caustic potash the yellow subli- 

 niate which is obtained when muriate of nickel is distilled in a 

 retort. The existence of this oxide deserves a more particular exa- 

 mination. 



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