556 Intelligence and Miscellaneous Articles. 



to dry air, behaved like crystals recently taken from their locality. — 

 Journ. de Pharm. et de Ch., Septembre 1846. 



ANALYSIS OF HEULANDITE. BY M. DAMOUE. 



The difference between the analyses of this mineral by MM. 

 Walmstedt, Thomson and Rammelsberg, consists in the presence of 

 a small quantity of soda and potash. The analysis of Damour gave 



Silica 59-64 



Alumina 1633 



Lime 7 - 44 



Soda 1*16 



Potash 0-74 



Water 1433 



99-64 

 This composition indicates that heulandite should be ranked with 

 zeolites. — Journ. de Pharm. et de Ch., Septembre 1846. 



EASY REDUCTION OF CHLORIDE OF SILVER. 



M. Levol states that this chloride is decomposed by being boiled 

 in a solution of potash in which a little sugar is previously dissolved ; 

 the sugar gradually reduces the metal in a short time, carbonic acid 

 gas being disengaged : after due washing the metal is obtained in 

 the pulverulent state. — Journ. de Ch. Med., Novembre 1846. 



ON THE CHEMICAL PROPERTIES OF RUTHENIUM AND SOME OF 

 ITS COMPOUNDS. BY DR. C. CLAUS. 



Ruthenium occurs in the residues of the Russian and also of the 

 American platinum ores, but only to the small extent of 1-1^ per 

 cent. It is a constituent of osmium-iridium ; the varieties of this 

 mineral analysed by me contained, besides osmium and iridium, 3-6 

 per cent, ruthenium, 10 per cent, platinum, 1^-2 per cent, rhodium, 

 with traces of copper, iron and palladium. The mineral described 

 by Herman under the name of irite contains 3 per cent. Ru along 

 with Rh, Pt, Os, Ir, FeO, Cr°-Os, Al a O>, SiO* and IrO*. The ru- 

 thenium does not occur in that portion of the platinum ore which 

 is soluble in aqua reyia ; it was discovered in the platinum residues, 

 because these always contain osmium-iridium. 



The following is the method which I adopt at present for its pre- 

 paration : — Osmium-iridium is powdered as finely as possible in a 

 cast iron mortar; the particles of iron removed from the mortar are 

 extracted with muriatic acid, and the powder mixed with chloride 

 of sodium treated at a faint red heat with moist chlorine gas. The 

 decomposed mass is extracted with cold water, and a few drops of am- 

 monia added to the concentrated brownish -red, almost opake solution, 

 which is then heated in a porcelain dish. A voluminous blackish-brown 

 precipitate, consisting of sesquioxide of ruthenium and oxide of os- 



