1818.] the Commencement of the Year 1817. Part I. 2l 



reduce the proportion of antimony to one twentieth of the mix- 

 ture. This alloy is then to be laminated, cut into slips, and 

 boiled in an excess of muriatic acid in a matrass for two hours 

 and a half. The antimony will remain undissolved, and it? 

 weight may be ascertained.— (Ann. de Chim. et de Phys. 

 iii. 376.) 



10. Tin and Bismuth.— M. Chaudet has likewise made expe- 

 riments on the separation of tin from bismuth by means of 

 muriatic acid. When an alloy is formed composed of equal 

 Aveie;hts of tin and bismuth, or of four parts tin and one of 

 bismuth, it is quite brittle. The muriatic, acid dissolves the tin 

 just as easily as if no bismuth were present, and about one per 

 cent, of the bismuth is at the same time dissolved. An alloy 

 composed of 25 parts of tin and one of bismuth may be lami- 

 nated ; and muriatic acid, of the specific gravity 1*190, when 

 boiled upon it 2^ hours, dissolves all the tin without touching 

 the bismuth. Hence the two metals, when united in this pro- 

 portion, may be easily separated by means of muriatic acid. — 

 (Ibid. v. 142.) 



1 1 . Tin and Lead.— Fischer ascertained, as had been pre- 

 viously done by Vauquelin and Proust, that when an alloy of tin 

 and lead is digested in acetic or muriatic acid, none of the lead 

 is dissolved ; but only a portion of the tin. But when this alloy 

 is digested in nitric acid, a portion of both metals is dissolved, 

 though the acid is found always to contain a greater proportion 

 of the lead. — (Schweigger's Journal, xx. 51.) 



12. Action of Aqua Regia on Antimony.— Butter of antimony 

 was formerly made by distilling a mixture of antimony and 

 corrosive sublimate ; but of late years the direct action of aqua 

 regia upon this, metal has been substituted. After the solution 

 is at an end, the liquid is evaporated to diyness in a retort. The 

 receiver is then removed, and the diy mass being made to pass 

 into a new receiver, constitutes very beautiful butter of antimony. 

 This process is much cheaper than the old one ; but it is liable 

 to some uncertainty, which M. Robiquet informs us may be 

 obviated by attending to the following observations : The propor- 

 tion of nitric acid ought to be to that of muriatic acid as one to 

 four : when the solution takes place slowly, the chlorine is not 

 dissipated as it is evolved. Hence there remains an excess of 

 it, a superchloride is formed which is not decomposed by the 

 evaporation ; the consequence is that butter of antimony is not 

 obtained. The inconvenience is easily obviated by putting the 

 liquid into a flask, and agitating it with powdered antimony 

 added in small quantities at a time, to prevent the evolution of 

 too violent a heat. By this addition the superchloride is decom- 

 posed, and the whole changed into a simple chloride, which 

 sublimes readily and constitutes chloride of antimony. When 

 the solution of the antimony takes place with great rapidity, the 

 chlorine is dissipated. There remains in consequence an excess 



