The mixture should be stirred often with a glass rod;
care should be observed not to apply too much heat,
for at a temperature of about 300 deg. the chlorine would be
expelled and leave a metallic precipitate, which would require
re-dissolving. Acid may at any time be added if necessary
to dissolve the gold, but it is advisable to add as little
excess as possible, as it would require more time to evaporate.
After all the gold has dissolved, and the liquid assumes a deep
red color, the solution should be allowed to cool, being stirred
nearly all the time. This salt is of a reddish-brown color.
It is rarely we find in our market good chloride of gold,
as common, salt is used for the bulk; and when the bottles
are labelled "15 grains," "20 grains," nine-tenths do not
in reality contain exceeding five grains of chloride of gold.
The salt is mixed with the above solution when it is cooling,
and gives bright yellow crystals, which some of our uninformed
operators conceive to be the best quality.

Chloride of Silver.--(Oxide of Silver.)--Take any quantity of silver
coin or other silver, roll or hammer it thin; cut in small pieces.
This in order to save time. Put the silver in a glass or earthen vessel
(Florence flask is best); pour in nitric acid and water, about three
parts of the former to one of the latter. The operation of cutting
up the silver may be facilitated by applying a gentle heat.
This blue solution consists of oxide of silver and oxide of copper,
both combined with nitric acid. Should the operator wish a pure
solution of silver, which, however, is not always used, he may obtain
it in the following manner:

To separate the two metals contained in the above solution from each other,