Chemical Science. 393 



hydrogen ; the solution was not affected by salts of baryta. 1 00 parts 

 of the dry salt lost 47.22, and as in consequence of the liberation of 

 sulphurous acid, it could not have produced a simple sulphuret nor 

 a sub-bisulphuret, the loss not being sufficient; it was suspected 

 to be a compound of sulphuret and oxide, like crocus of antimony. 

 This was proved by passing sulphuretted hydrogen over it, for 

 water was formed, and the whole converted into simple sulphuret. 

 The oxy-sulphuret of manganese is green, unaltered by air, dis- 

 tinguished from the sulphuret by its brighter colour and greater 

 difficulty of oxidation in the air by heat. It is composed of 



Manganese . 70.26] JSulphuret of Manganese . 55 

 Sulphur . . ]9.86> or 1 0xide of Manganese . . 45 

 Oxygen . . 9.88] "■ ° 



When protoxide of manganese, or sulphate of manganese, is 

 reduced by sulphuretted hydrogen, a sulphuret is obtained, con- 

 taining one atom of manganese, and one atom of sulphur. 



Sulphate of Zinc, heated in hydrogen, gave sulphurous acid 

 and water ; and left a pulverulent yellow substance, containing both 

 sulphuret and oxide of zinc, but no sulphuric acid. Sulphuretted 

 hydrogen caused the liberation of water, and left a sulphuret. 

 One hundred parts of sulphate gave in three experiments 56.07, 

 58.23, 56.95. Here the weight of the oxy-sulphuret is too much; 

 and we must conclude, that when decomposed in this way more than 

 half becomes sulphuret, and the rest oxide, but without any constant 

 proportion being observed. The native sulphuret of zinc contains 

 One atom zinc . . 66.34 

 One ditto sulphur . . 33.66 



10.00 



Sulphate of Cobalt, gave sulphurous acid and water, and left per 

 cent. 53.62 of oxy-sulphuret ; so that half of the sulphate becomes 

 sulphuret and half oxide. When sulphate of cobalt is decom- 

 posed by sulphuretted hydrogen, a sulphuret is produced, con- 

 taining more than one atom of sulphur, and apparently composed 

 of an atom of simple sulphuret, and an atom of sesqui-sulphuret. 



Sulphate of Nickel, is readily decomposed by hydrogen, at 

 first giving off water and sulphurous acid ; and ultimately sulphu- 

 retted hydrogen. 1015 of sulphate left 490 of a pale yellow cohe- 

 rent metallic substance, attracted by the magnet, and with 

 marks of fusion here and there. When analyzed, it proved to be 

 a compound of two atoms nickel, one atom sulphur. 



Oxide of nickel, with sulphuretted hydrogen, gave a pulverulent 

 dark grey substance, not attracted by the magnet, and more infu- 

 sible than the sub-sulphuret. 11 80 of oxide gave 1438 of sul- 



VoL. XVIII. 2 D 



