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Scientific American Supplement, No. 623, December 10, 1887 by Various
page 60 of 143 (41%)
need for it. In fact, it is prejudicial to do so. I place the films
face uppermost in the dish, and pour on the developer on the center of
the films. You will observe they lie perfectly flat, and are free from
air bubbles. Rock the dish continually during development, and when
the high lights are out add from 10 to 90 minims C, and finish
development and fix. The negatives being complete, I ask you to
observe that both are of equal quality, proving the latitude of
exposure permissible.

I now coat a piece of glass half an inch larger all round than the
negative with India rubber solution (see Eastman formula), and
squeegee the negative face downward upon the rubber, interposing a
sheet of blotting paper and oilskin between the negative and squeegee
to prevent injury to the exposed rubber surface, and then place the
negative under pressure with blotting paper interposed until
moderately dry only.

I then pour hot water upon it, and, gently rocking the dish, you see
the paper floats from the film without the necessity for pulling it
with a pin, leaving the film negative on the glass. Now, the
instructions say remove the remaining soluble gelatine with camel's
hair brush, but, unless it requires intensifying, which no properly
developed negative should require, you need not do so, but simply pour
on the gelatine solution (see Eastman formula), well covering the
edges of the film, and put on a level shelf to dry.

I will now take up a negative in this state on the glass, but dry, and
carefully cut round the edges of the film, and you see I can readily
pull off the film with its gelatine support. Having now passed through
the whole of the process, it behooves us to consider for a few minutes
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