1825.] Scientific 'Sotices-^Chemistry. 151 



2. Compound of Muriate and Ilydrosulpliurel of Oxidulc of 



Antimonij. 



Sulphuretted hydrogen throws down from a solution of the 

 muriate of oxidule of antimony a lively pomegranate yellow 

 coloured precipitate, which has been hitherto regarded as a pure 

 hydrosulphuret of oxidule of antimony : it is, however, a combi. 

 nation of this salt with the neutral muriate ot oxidule of anti- 

 mony The latter salt may be expelled by heat, and sulphuret 

 of antimony remains behind; the same decomposition may be 

 effected by exposing the precipitate for some time in a close 

 vSto the light o1-the sun.-(L.Gmelin. Handbuch der theo- 

 retischen Chemie.) 



3. Composition of White Precipitate. 



We copy the following from a note, at the conclusion of Mr. 

 Brande's paper, entitled " Facts towards the Chemical History 



"" HavTng^inferred from various experiments that the " white 

 precipitate " was a compound of one proportional of peroxide ot 

 mercury, and one of muriate of ammoma, Mr. Hennel verified 

 his opinion as follows : A solution of one proportional of corro- 

 sive sublimate (= 272) was mixed with a quantity of solution 

 of ammonia, containing two proportionals (17 x 2 = ci4) ot that 

 alkah; a neutral mixture resulted, white precipitate was tormed, 

 and one proportional of muriate of ammoma (ammonia 17 + 

 muriatic acid 37 = 54 of muriate of ammonia) was found in 

 solution. In this case, the two proportionals of chlorine in the 

 sublimate (36 x 2 = 72) were converted at the expense ot 

 2 proportionals of water, into 2 of muriatic acid, which, uniting 

 with the ammonia, formed 2 of muriate of ammonia, the 

 2 proportionals of the oxygen from the water (equivalent to the 

 2 of hydrogen transferred to the chlorine) united to the 1 pro- 

 portional of mercury in the subhmate, to form 1 of peroxide ot 

 mercury, which fellni combination with 1 of muriate of ammonia 

 to constitute white precipitate ; while the other proportional ot 

 muriate remained, as above stated, in solution. The equivalent 

 number, therefore, of white precipitate, is 270, and it consists ot 



1 proportional of peroxide of mercury. . . = 216 • • • • ^J^ 

 \ muriate of ammonia . . . . = 54 .... 20 



270 100 



Having thus synthetically established the composition of 

 white precipitate, the foUowmg analytical experiment was made 

 upon it : 270 grains were dissolved in hydrocyanic acid, and 

 sulphuretted hydrogen was passed through the solution till it 

 occasioQed no further change; the precipitate was then col- 



