METALLIC OXIDES* S15 



residue was white oxide, and the ga0 verf pure oxigen. These 



experiments prove, that the yellow oxide is decomposed by the 



heat by losing part of its oxigen j and as 03'75 p. of white 



oxide contain 20 24 of oxigen, it is clear, that the yellow oxide 



loses, on this occasion, one-fourth of its oxigen, and that it 



contains if as much oxigen as the white oxide, and twice as 



much as the fusible oxide (oxidum stibiosum.) 



There are several other metlfbds of producing the yellow Other me- 



oxide (a.) If into a long-necked tubulated phial a certain *." ods of P™' 



° r ducmg yellow 



quantity of metallic antimony be put, and heat be applied to a oxide (a) by 



cherry redness, and continued four or five hours, the antimony mere heat; 

 gradually combines with oxigen - f a small quantity of white 

 oxide sublimes into the neck of the glass, another portion es- 

 capes out of the aperture ; but the greatest part of the oxided 

 metal forms a yellow crust round the border of the fused me- 

 tal. In this form the yellow oxide is not crystallized j it has 

 much tenacity, and is difficult to break. 



(b) If one part of antimony in powder be burned with (b) by com* 

 6 p. of nitre in a red hot crucible, the burned mass is then J!™.^ 011 Wltl1 

 decomposed with nitric acid, which leaves a white powder not 

 dissolved. This powder is a combination of the yellow oxide 

 with water, which may be driven off by heat over a spirit 

 lamp. The oxide is then left of a very clear and fine yellow 

 colour. 



The degrees of oxidation of antimony may therefore be Degrees of 



expressed by the series 1, l£, 2 : but we have not compre- oxlda , t ! on . 

 ,,,,,,...,.. ,. . . , t statedinsenei 



bended the suboxide in this series, which contains less oxigen. l,— ,4, 6, 8. 



than the first of the series. If, from what I have endeavoured 

 to make probable with regard to sulphur and arsenic, the quan- 

 tity of oxigen in the suboxide be one-sixth of that in the 

 white oxide, or one-fourth of the fusible oxide, the series 

 will be I, — ,4,6,8. If, on the contrary, future experiments 

 should prove, that the oxigen in the suboxide is only, in fact, 

 half that of the fusible oxide, the series will become 1, 2, 3, 4. 

 Although it is very clear, that the middle numbers must be 

 deficient in precision, particularly when, at the same time, 

 they are not founded upon good experiment, yet we must, 

 amidst results so little fixed, content ourselves with an approxi- 

 mation of this nature. And by assuming, that the oxidum 

 stibiosum is composed of 100 parts of metal, and 18*6 p. of 

 Y ,2 oxigen ; 



