C.
Pure carbonate of potash. 1 ounce. 
Water to make up to 10 ounces.

D.
Bromide of potassium. 1 ounce. 
Water to make up to 10 ounces.

I have here two half-plate films exposed at 8:30 A.M. to-day, one with five and one with six seconds’ exposure, subject chiefly middle distance.  I take 90 minims A, 10 minims D, and 90 minims B, and make up to 2 ounces water.  I do not soak the films in water.  There is no 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 the causes of failure in the hands of beginners and their remedies:  1.  The rubber will not flow over glass?  Solution too thick, glass greasy. 2.  Rubber peels off on drying?  Dirty glass. 3.  Negative not dense enough?  Use more bromide and longer development. 4.  Gelatine cracks on being pulled off?  Add more glycerine. 5.  Gelatine not thick enough?  Gelatine varnish too thin, not strong enough. 6.  Does not dry sufficiently hard?  Too much glycerine.—­E.H.  Jaques, Reported in Br.  Jour. of Photography.

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HOW DIFFERENT TONES IN GELATINO-CHLORIDE PRINTS MAY BE VARIED BY DEVELOPERS.

The following formulae are for use with gelatino-chloride paper or plates.  The quantities are in each case calculated for one ounce, three parts of each of the following solutions being employed and added to one part of solution of protosulphate of iron.  Strength, 140 grains to the ounce.