562 Intelligence and Miscellaneous Articles. 



pure state. The crystals of this salt are so minute that their form 

 cannot be recognised with the naked eye ; with a magnifying power 

 of 300 times diameter they appear as perfectly transparent red prisms 

 with pointed terminal surfaces, probably belonging to the rhombohe- 

 dral system. The salt is readily soluble in water, insoluble in spirit of 

 0*889, and scarcely soluble in a concentrated solution of chloride of 

 ammonium ; its solution is of a rose colour playing into violet, and 

 cannot be distinguished from that of the chloride of rhodium and 

 sodium ; it is scarcely affected by sulphuretted hydrogen, and only 

 deposits after some time a little yellowish-brown sulphuret, without 

 the liquid losing its red colour. If to the solution of this salt an 

 alkali is added, no precipitate results, but on evaporation a yellowish- 

 brown gelatinous hydrated oxide separates, which contains a con- 

 siderable quantity of alkali, and when heated on platinum explodes 

 slightly with a sudden glowing. A concentrated solution of this 

 salt in water is only partially precipitated by alcohol; the greater 

 portion remains in solution with a red colour, and is not reduced to 

 a lower chloride on evaporation. The blue reaction of the sesqui- 

 chloride of ruthenium cannot be produced in the solution of this 

 salt even when sulphuretted hydrogen is passed through it for six 

 hours. The metal reduced from this salt is ruthenium, for it yielded 

 on ignition with nitre rutheniate of potash, and this with muriatic 

 acid sesquichloride of ruthenium, in which the blue reaction could 

 be produced by sulphuretted hydrogen. 



Sulphurets. 

 It is highly probable that as many combinations of ruthenium 

 with sulphur exist as this metal forms oxides, but their preparation 

 is accompanied with numerous difficulties. When, for instance, pow- 

 dered ruthenium is mixed with sulphur and heated in an atmosphere 

 of carbonic acid, there is no appearance of any chemical reaction, 

 the sulphur distils off, and the ruthenium increases but little in 

 weight. The precipitates obtained from the chlorides by sulphu- 

 retted hydrogen by no means correspond to those compounds ; they 

 always contain too much sulphur, and are very probably mixtures 

 of sulphurets with sulphur ; their analysis is very difficult, as they 

 easily become oxidized in drying, and are partially converted into 

 sulphate. When heated, in order to remove the water, they explode 

 faintly with incandescence; and when treated with fuming nitric 

 acid, they are likewise oxidized with a faint explosion and a shower 

 of sparks. They dissolve, it is true, in ordinary nitric acid very 

 easily, but the sulphuric acid formed cannot be precipitated pure 

 from this solution by a salt of baryta ; it is coloured yellowish, and 

 always contains some sulphate of ruthenium, which cannot be re- 

 moved by any solvent. When the sulphuret precipitated from the 

 sesquichloride is heated in a reduction -tube through which carbonic 

 acid is passed, water and sulphur are removed, accompanied by a 

 glowing and explosion, and the blackish-gray metallic powder left 

 yields results which correspond to the formula Ru 2 S 3 . The sul- 

 phuret which is precipitated when sulphuretted hydrogen is passed 



