epare the toning baths, dissolve the ounce of uranium nitrate in 10
ounces of water. The water should be distilled if this is easily
obtainable, and the solution should be kept in an orange-glass bottle or
an ordinary bottle protected from light by a non-actinic paper wrapping.
Dissolve the ounce of potassium ferricyanide in 10 ounces of water. Keep
this also in an orange-glass bottle, well corked. There are many cautions
about this particular salt, and it has been said that it will not keep in
solution. In my practice I find no difficulty whatever in the use of a
solution six months old, despite the difficulties mentioned in the
text-books.

To tone the bromide prints, first note that the prints should have been
developed and fixed and washed just as usual. It is necessary that prints
to be toned shall contain no trace of hypo. To secure this, the prints
should be specially prepared for toning by being again thoroughly washed,
as any hypo remaining in the print will cause spots and streakiness. With
care at this stage the toning will give clean and bright prints, which
should be as permanent as the original bromide print.

I cannot give the reason why, but, as a general rule, bromide prints tone
better if the print has been dried after washing and rewet just before
toning. There may be a chemical reason for this, but I am inclined to
think that it is a physical one, viz., that the emulsion is softer after
its first washing than after having been dried and wet, so that it allows
toning solution to get into the film more quickly. This naturally results
in more rapid toning, and quick toning does not yield as good prints as a
slower and more gradual building up of the color image.

Having the print ready for toning as here outlined, take 1 dram of the
uranium solution, add 1/2 dram of acetic acid and then 5 ounces of water.
In a separate graduate put 1 dram of ferricyanide solution and 5 ounces of
water. Just before toning, pour these two solutions together into the
third graduate and use immediately. To proceed, lay the rewetted print
face up in a clean tray and flow the freshly made toning bath (the two
solutions combined) over the print. The print and tray must be kept in
motion by gentle rocking during the toning operation. The toning solution
tends to throw a red precipitate as it works. This precipitate should not
be permitted to settle on the face of the print. Some workers tone their
prints face down, but I do no