COMBINATIONS OF OXIMURIATIC ACID AND METALS. 131 



Klaproth concludes from his experiments, that the oxide and^ of bis- 

 of bismuth, prepared by means of nitric acid, contains 177 ^Oxideof bis- 

 per cent of oxigen ; and in consequence this oxide has been muth.) 

 considered distinct from that which is formed by direct calci- 

 nation of the metal, and which contains a much smaller pro- 

 portion. But there is reason to believe, that this difference 

 does not really exist, and that there is only one known oxide 

 of bismuth, and that Klaproth's oxide was a hydrated oxide j 

 for I have found that 100 grains of bismuth, converted by 

 nitric acid into oxide, precisely in the same manner as the 

 protoxide of antimony was more highly oxidated, gained only 

 iri grains. Klaproth did not heat his oxide to redness, and 

 hence apparently the discordance. From the above result, 

 which I have confirmed by repetition of the experiment, oxide 

 of bismuth seems to contain 10 per cent of oxigen ; and bis- 

 muth being as 67B, the oxigen in the oxide is to the chlorine 

 in the butter of bismuth, as 75 to 34*2. 

 6. On the Refalion between the Proportion of Sulphur in the 



Sulphurets, and the Proportions of Chlorine in some of the 



Combinations of Chlorine a?id the Metals. 



The last section afforded proofs of the useful application of Proportions 

 the general analogy of definite proportions in correcting the compared with 

 results of chemical analyses. In the present section, it is my those of the 

 intention to pursue a little farther the plan that I have adopted oxSiafic °^ 

 in the preceding, and to apply another test to the analyses of acid, 

 the combinations of the metals and chlorine, by comparing 

 some of them with the combinations of the same metals and 

 sulphur. 



I was first led to examine the sulphurets of tin on a different 

 account, Aurum musivum, it has been observed, is formed of^au'rum^'mu- 

 when stannane is heated with sulphur. According to Mr. sivum. 

 Proust, this substance is a sulphuretted oxide of tin. Were 

 this opinion correct, an argument might evidently be deduced 

 from it in favour of the existence of oxigen in chlorine. 

 To satisfy myself respecting this, I endeavoured to ascertain 

 whether any sulphureous acid gas is produced by the decom- 

 position of aurum musivum by heat, as it is commonly asserted. 

 I heated to redness in a bent luted green glass tube, connected 

 with a pneumatic mercurial apparatus, about 20 grains of 

 aurnm musivum^ prepared by the decomposition of stannane 

 K 2 witii 



