on the Haloid Compounds of Mercury. 443 
B.—As the above method necessarily throws the chlorine and mercury estimate 
rather too high, the following experiment was made, in which the necessary loss pro- 
duces an opposite effect : 
101,37 of the powder were boiled with strong muriatic acid, and an acid solution 
of proto-chloride of tin added. The reduction of the quicksilver took place readily, 
and large well-formed globules appeared; the metal collected and carefully dried, 
weighed 89,39 grains, or 100 of the powder had given 88,18. 
C.—51,42 of the grey powder were dissolved in dilute aqua regia, and a current of 
sulphuretted hydrogen in excess passed through the liquor. It was found, that owing 
to free chlorine, the sulphur precipitated invalidated the result. The whole was 
therefore mixed with nitric acid, and boiled until the sulphuret of mercury was com- 
pletely decomposed ; the liquor was then freed from the particles of pure sulphur and 
evaporated until all free nitric acid and chlorine were completely dissipated. Being 
then treated by sulphuretted hydrogen, it yielded a sulphuret, pure and jet black, 
which collected and dried, weighed 52,39 grains, consisting of 
Sulphur 7,19 
Mercury 45,20 
The 51,42 grains therefore contained 45,20 of mercury 
or 100,00 - - - 87,90 
In this experiment so much ammonia was lost by the treatment with nitric acid, that 
its quantity could not be determined, 
D.—As in none of these former analyses had the ammonia constituent been de- 
termined, the following experiments were made for the purpose of ascertaining its 
52,39 
precise quantity : 
Ist. 66,43 grains were boiled with an excess of solution of iodide of potassium, 
and the flask being connected with a bent tube dipping into dilute muriatic acid, the 
heat was kept up until all the ammonia and about half the water had passed over. 
The liquor was then evaporated to dryness, and yielded a residue of 6,96 grs. of sal- 
ammoniac, consisting of 
Muriatic acid 4,73 
Ammonia 2533 
or 100 of powder gives 3,36 of ammonia. 
The action of potash on the grey powder liberates ammonia likewise ; but it was 
found so difficult to obtain complete decomposition that the method was abandoned. 
Another process tried, consisted in repeatedly distilling strong muriatic acid off the 
powder, in order to convert it into metallic mercury, corrosive sublimate, and sal- 
ammoniac, and thus obtain a quantative result ; but this method also was found of so 
imperfect action, that it could not be well applied. 
