137 / 160
GIGGLE WATER
139
ounce phials, adding 20 drops muriatic acid to each. Both
the above tests will throw down the least quantity of lead
from wines, as a very sensible black precipitate. As iron
might be accidentally contained in the wine, the muriatic
acid is added to prevent the precipitation of that metal.
This acts in the same manner as Haluiemann's test.
285. TO DISTINGUISH ARTIFICIALLY
COLORED WINES
As the real coloring matter of wine is of difficult solu-
oility in water free from tartaric acid, Blume proposes
to make this fact of practical use in testing the purity of
wine. A crumb of bread saturated in the supposed wine is
placed in a plate of water; if artificially colored, the water
soon partakes of the color; but if natural, a slight opales-
cence only will be perceptible after a quarter of an hour.
286. TO DETECT LOGWOOD IN WINE
M. Lapeymere, having observed that haematine, the
coloring principle of logwood, gives a sky-blue color in
the presence of salts of copper, proposes the following
test for logwood in wines: Paper is saturated with a
strong solution of neutral acetate of copper, and dried.
A strip of this is dipped into the suspected liquor, and,
after removal, the adhering drops are made to move to
and fro over the paper, which is finally to be carefully