Intelligence and Miscella7ieous Articles, 311 



perfectly resists the action even of concentrated acids ; it is only by 

 heating it in nitric acid, and then adding muriatic, that sufficient 

 action is exerted to convert all the sulphur into sulphuric acid. 



When this compound is treated with chlorine gas and heat, 

 chloride of sulphur is at first disengaged, and afterwards sublimate. 

 The alkalies and their carbonates blacken it, especially with the 

 assistance of heat: as the results of this decomposition, the liquid 

 contains chloride of potassium and sodium, and the black precipi- 

 tate consists of a mixture of oxide and sulphuret of mercury ; there 

 is no chloride of mercury, as has been supposed. The different ana- 

 lyses which I have made having given results almost identical with 

 the data of calculation, this compound is formed of] atom of chloride 

 of mercury = S6-8, and 2 atoms of sulphuret of mercury = 63-20. 

 Thus, by the action of sulphuretted hydrogen on a solution of sub- 

 limate, there is first obtained sulphuret of mercury, which, com- 

 bining with the undecomposed chloride, forms a substance insoluble 

 in water. If the quantity of sulphuretted hydrogen be too great, 

 all the chloride is decomposed, and all the precipitate is sulphuret 

 of mercury. 



Analogous phasnomena are observed when a solution of bromide 

 of mercury is similarly treated. The solution becomes milky ; the 

 dried precipitate resembles the former, except in being slightly yel- 

 low ; it acts in the same way with the concentrated acids ; the al- 

 kalies blacken it, but not so strongly ; it is decomposed by heat into 

 bromide of mercury and sulphuret of mercury. The composition of 

 this body is analogous to the preceding ; that is to say, it is formed 

 of an atom of bromide of mercury and two atoms of sulphuret of the 

 same metal. 



The iodide and fluoride of mercury treated with sulphuretted 

 hydrogen, furnish precipitates, the combination of which is abso- 

 lutely analogous. The precipitate of the latter is white and heavy, 

 and is distinguished from the others bybeing decomposed by boiling 

 water, into fluoride and black sulphuret of mercury; when heated 

 in a glass tube, one end of which is closed, it is resolved into fluo- 

 silicic gas and mercury, whilst at the point of the greatest heat sul- 

 phuret of mercury sublimes. 



This precipitate is decomposed by concentrated sulphuric acid 

 when heated (which does not occur with the others). Treated 

 simply with the alkalies, it becomes red ; on the contrary, it becomes 

 black when boiled with these bodies. 



The mercurial oxisaits act with sulphuretted hydrogen in the same 

 manner as the combination of this metal, with bromine, chlorine, and 

 fluorine. The precipitates which are obtained at first are white, and 

 more readily deposited ; they are also more easily filtered ; they are 

 composed of sulphuret of mercury and a small quantity of the salt 

 employed. Thus the precipitate obtained with nitrate of mercury is 

 white; wiien heated in a glass tube, it yields a small quantity of sul- 

 phuret of mercury, wljich sublimes, much metallic mercury, nitrous 

 vapours, and sulphuric acid : it acts with acids in the same manner 

 as the precipitate furnished by the chloride : the alkalies give it first 



a yd. 



