416 Progress of Foreign Science. 



once more carried off by the potash, so that we may make it 

 pass in succession a considerable number of times, from the 

 charcoal to the solution, and from the solution to the charcoal. 

 It is, however, observed, that these successive solutions termi- 

 nate in altering the indigo ; and, at each new discoloration, 

 the liquor retains a faint yellowish colour, which indicates the 

 decomposition of a small quantity of indigo. 



We may conclude from all that we have seen, that the dis- 

 colouring property is inherent in charcoal ; but that it becomes 

 manifest only when the charcoal occurs in certain physical con- 

 ditions, among which porosity and division hold the first rank ; 

 that no charcoal can discolour when it has been heated strongly 

 enough to become hard and brilliant ; that all, on the contrary, 

 possess this property when they are sufficiently divided, not by 

 a mechanical action, but by the interposition of some substance 

 which opposes their aggregation ; and that the superiority of 

 animal charcoal, such as that of the blood and geltaine, pro- 

 ceeds especially from its great porosity. — Jour, de Pharm. 

 June, 1822. 



Analysis of the Bark of the Quassia Simarouba of LinneeHS. 

 By M. Morin. 



1. A resinous matter ; 



2. A volatile oil having the odour of benzoin ; 



3. Acetate of potash ; 



4. An ammoniacal salt ; 



5. Malic acid, and traces of the Gallic ; 



6. Quassine; 



7. Malate and oxalate of lime ; 



8. Some mineral salts, oxide of iron, and silica ; 



9. Ulmin and ligneous matter. 



Analysis of the Smelt (Salmo Eper/anus of Ltnnceus). By 

 M. Morin. 



1. Albumen ; 



2. Mucus ; 



3. Osmazome ; 



4. Muriate of ammonia ; 



5. A gelatinous matter ; 



6. Muriate of potash. 



7. Phosphates of potash, magnesia, iron, lime; 



8. Carbonate of lime ; 



9. An oily matter ; 



10. Phosphorus ; 



11. Animal fibre.— /our. de Pharm. Feb. 1822. 



New Researches on the Composition of the antimoniated sul- 

 phuret of Silver, the red Silver of Andreasherg. By M. P. A. 

 Boosdorff. — The pounded ore was put into an apparatus, simi- 



