Water 1 quart.
Into this put half as many grains of pure chloride of gold as you
have sheets of paper to tone; after adding the gold make the
solution alkaline by adding enough of a strong solution of a
carbonate or bicarbonate of soda to turn red litmus paper just
blue; then add a pinch of salt, and the toning solution is ready
for use. When half your prints are toned, or the toning proceeds
too slowly, add more gold, allowing not over 1 grain of gold for
each sheet of paper. When all the prints are toned, put the toning
solution into a bottle to keep for the next time, when it will
probably work better than at first; [p077] use it until it
becomes badly discolored, then put it into a large bottle to save
the waste gold.
The toning must be done in a flat dish that is as large as the
largest print that requires to be toned.
Your toning solution being ready, the prints are now to be
prepared for toning by being deprived of all excess of silver and
free chloride not acted on by the light; in order to do this, put
them one by one in a large dish full of water, in this dish keep
them in motion for some little time, then prepare another dish
containing the same amount of water slightly acidified with acetic
acid, and remove the prints into this one by one as before,
keeping them in motion; they will at once commence to turn red,
and when they are so they may be taken out, the waters of these
two washings must be saved for the silver contained therein.
The prints require two more waters after the acid, when they are
ready for toning.
Immerse half a dozen or more of the prints, one at a time, in the
toning solution and watch the change of color.
They may at first become a little redder from the action of the
salt in the solution, but they will soon change to a brown and
then to a bluish or grey brown. And when the faces have become as
clear and white as to suit as finished pictures, remove them to
fresh water and proceed with another batch until all are done.