s 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._

* * * * *

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.

_Slaty Blue._

1.--One part of the above solution
to three parts of a solution of citrate of ammonia.

_Greenish Brown._
2.--Citric acid. 180 grains
Carbonate of ammonia. 50 "

3.--Citrate of ammonia. 250 grains.
Chloride of sodium. 2 "

4.--Citrate of ammonia. 250 grains.
Chloride of sodium. 4 "

_Sepia Brown._
5.--Citrate of ammonia. 250 grains.
Chloride of sodium. 8 "

_Clear Red Brown._
6.--Citric acid. 120 grains.
Carbonate of magnesia. 76 "

_Warm Gray Brown._
7.--Citric acid. 120 grains.
Carbonate of soda. 205 "

_Deep Red Brown._
8.--Citric acid. 120 grains.
Carbonate of potash. 117 "

_Green Blue._
9.--Citric acid. 90 grains.
Carbonate of soda. 154 "
Citrate of potash. 24 "
Oxalate of potash. 6 "

_Sepia Red._
10.--Citric acid. 80 grains.
Carbonate of soda. 135 "
Citrate of potash. 12 "
Oxalate of potash. 3 "

11.--Citric acid. 108 grains.
Carbonate of magnesia. 68 "
Carbonate of potash. 12 "
Oxalate of potash. 3 "

_Sepia Yellow._