on the Haloid Compounds of Mercury. 427 
These results, which agree very closely with each other, give us as a mean from 
one hundred of white precipitate 92,98 of calomel, containing 
Mercury 79,14. 
Chlorine 13,84. 
C.—To obtain a value for the quicksilver by reduction, the usual method was pur- 
sued. ‘The white precipitate was dissolved in muriatic acid, and precipitated by solu- 
tion of protochloride of tin. The quicksilver was dried in the cold, and there was 
obtained from one hundred grains of white precipitate, in one experiment, 77,3, and 
in a second 78,1 of mercury, giving a mean of 77,7 per cent. 
D.—105,40 of white precipitate were dissolved in muriatic acid, and the liquor 
diluted with four times its volume of water. Sulphuretted hydrogen was then passed 
through until the resulting precipitate became perfectly black, and deposited readily. 
The whole was then thrown on a weighed filter, and washed with distilled water. 
The washings and liquor were cautiously evaporated to dryness, and the residue 
weighed. ‘There were thus obta ined : 
Filter and sulphuret 143,58 grs. 
Filter - - 48,35 
Bisulphuret of mercury " 95,23 
Consisting of Mercury - rink, 82,17. 
Sulphur — - - 13,06 
And Sal-ammoniac - - 23,59 grs. 
Consisting of Muriatic acid - 16,04 
Ammonia - - [eco 
Or from 100 of white precipitate : 
Mercury - 77,96 
Ammonia - : 7,16 
E.—For the determination of the ammonia of white precipitate, potash or lime 
cannot be employed, as only one-half of the ammonia is thus separated. In addition 
to the mode applied in (D), which is perhaps the best, the following means were had 
recourse to : 
a. 100 grains of white precipitate were introduced into a flask, and a solution of 
sulphuret of barium poured on it; from the flask a bent tube conducted to a tall jar 
containing dilute muriatic acid. By the application of heat, the ammonia and much 
water were driven over ; the liquor in the jar was then evaporated to dryness. There 
remained sal-ammoniac 21,57 grs. consisting of— 
Muriatic acid 14,85 
Ammonia 6,72 
