but not splintered, apply Canada balsam
with a toothpick to the edges of the broken parts, and press them firmly
together, keeping the negative on a flat surface during the process, a
glass plate a little larger than the negative being the best thing to
use. When the balsam is thoroughly dry, flow the negative with varnish,
and as soon as it begins to set cover it with a piece of glass the size
of the negative. When dry, bind the edges together with strips as before
directed. If the negative is very badly broken, it should be enclosed
between two pieces of plain glass, putting on the second in the same
manner, after the first is dry. Bind the three together.

An excellent paste for binding negatives and lantern slides is made of
rice flour. Mix rice flour with water till it is smooth and free from
lumps. Set the dish containing it into another of hot water, and boil
till it becomes thick and semi-transparent, stirring it all the time.
When done it should be about the consistency of laundry starch made for
collars and cuffs. This paste is very strong--in fact, almost as durable
as cement. If a few drops of carbolic acid are added to it, it will keep
for some time. The bottle should be tightly corked when not in use.

If the film has not been broken it can be removed from the glass in the
same way that films are stripped, and transferred to another clean
plate.

For very valuable negatives it is a good plan to make a paper negative,
in case of accident to the glass one. A paper negative is made by taking
a good print of the negative and waxing it according to directions given
in No. 782 "answers to queries." Make a print from this waxed positive,
supporting the paper while in the printing frame by a sheet of plain
glass. Tone and fix this print, which will be a negative. Wax it, and if
you are so unfortunate as to break the original, you will still have the
paper copy, which can be used in its place.

For negatives that can be replaced it is not wise to spend the time in
repairing them if broken, but it sometimes happens that a valuable one
is broken which cannot be duplicated, and with careful handling it can
be made "as good as new."

SIR KNIGHT HARRY T. LUTHER, New York, asks what causes his
negatives to turn yellow, and if there is any remedy for it. The
reason why negatives turn yellow is usually because they have not
been washed long enough. They should be washed in running water an
hou