The ferrotype and how to make it - The Grian Press

80 THE FERROTYPE.
will pour the half-gallon more, or less, of so-
lution ; the effect is to change the transparency
of the solution to a dense milky whiteness, which
is iodide of silver, set free by reducing the
strength of the solution. This should now be
filtered to remove the iodide, after which it
shouM be returned to the evaporating dish, and
set over a fire, and boiled down to less than the
original quantity; this will effectually remove,
by evaporation, the alcohol and ether. There
will, also, during the process of boiling down,
be deposited a black, muddy sediment, which is
partly iodide of silver and partly organic matter.
The solution should be then diluted with cold
\vater enough to restore to the original quantity,
poured into a white glass bottle, and set in
the sunshine for a day, or until it is again re-
quired for use, when it should be strengthened by
adding fresh nitrate of silver, to restore it to the
standard strength of 45 grains to the ounce fluid.
During the summer season, when the sun is
bright and warm, it is not necessary to boil the
bath solution to remove the alcohol and ether.
The bath, when unfit for further use, should be
neutralized and set in the sunshine, after being
diluted with sufficient water to restore it to its
original bulk. It will be well to notice that, in
diluting or adding water to an old bath, the
water should not be poured into the bath, but the
bath solution should be poured into the dish con-
taining the wa^er it is intended to add, the effect