OF ASCERTAINING THE PRESENCE OF DIFFERENT METALS. 
161 
the platina spatula, and the zinc applied to the fluid, the mercury was pre- 
sently reduced. The experiment was successfully repeated with diluted aqua- 
fortis, instead of muriatic acid. 
Solution of corrosive sublimate was respectively mixed with saliva, sheep’s 
blood, and ox bile ; the zinc being applied to each, on platina, the mercury 
was soon reduced. 
A few drops of solution of corrosive sublimate were mixed with some human 
bile, and watery fluid discharged from the stomach, and rather more than half 
its bulk of muriatic acid was added ; a small teaspoonful of the mixed fluids 
was put into the platina crucible, and the zinc applied for about two minutes, 
when the surface of the crucible had acquired a dark grey colour ; on being 
heated, metallic mercury was obtained. The experiment was repeated, with 
similar results, in a platina gilt crucible. 
A solution of corrosive sublimate, in small quantity, was mixed with milk ; 
muriatic acid, equal to about one half the milk, was added. Some of the mixed 
fluids was put into the platina crucible, and the zinc being applied a short 
time, a grey surface of mercury appeared on the platina. A similar experi- 
ment was made in the platina gilt crucible, which soon exhibited a partially 
whitened surface. From both experiments mercury was sublimed. 
A few drops of solution of corrosive sublimate were mixed in a cup of tea 
sweetened with sugar and cream. About a teaspoonful was put into the pla- 
tina crucible, with nearly an equal bulk of muriatic acid. A slip of zinc being 
applied for about a minute, a greyish substance was found at the bottom of the 
crucible, which, when washed, dried, and heated, afforded metallic mercury. 
These experiments were repeated with success, both in the platina crucible and 
in the platina gilt crucible ; and precisely similar results were obtained with 
coffee, under like treatment. 
It is proper to remark, that the experiments noticed in this section, were, in 
general, carried on only for a few minutes, so that the decompositions were 
mostly partial, and probably in no instance complete. This statement is con- 
firmed by facts, for I repeatedly found that after a given effect had taken place 
in the platina crucible in a few minutes, a still further effect was soon pro- 
duced, by transferring the same materials to the platina gilt crucible. 
MDCCCXXXI. 
Y 
