Page 23 - The Wellington photographic handbook

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causes put together. For those who have not yet learnt how to
expose correctly, the WELLINGTON EXPOSURE DISC is
recommended. This will be found the simplest and easiest " short-
cut." If the H. & D., Watkins', or Wynne's systems are preferred,
there is no reason why they should not be employed.

THE DEVELOPER.

Any of the developing substances on the market will give
excellent results with WELLINGTON Plates if used in correct
proportions and in solutions of suitable strength. Both pyro-soda
and metol-hydrokinone will be found very suitable. Pyro-ammonia
—although not recommended to the beginner—may be used if
preferred. The following are the formulae recommended :
PYRO-80DA.*
No. 1.
Pyrogallic Acid 1 ounce 50 grammes
Sodium Sulphite (cryst.) ... 2 ounces 100
Citric Acid 40 grains 4-5 „
Water to ... ... ... 10 ounces 500 c.c.
No. 2.
Sodium Carbonate (cryst) ... 8 ounces 100 grammes
Sodium Sulphite (cryst) ... 8 „ 100 ,,
Water to 80 1 litre
For Normal Work take 1 ounce (30 c.c.) of No. 2 and 1 dram (4 c.c.) of
No. 1, with Water 1 ounce (30 c.c).
For Studio Work take 1 ounce (30 c.c.) of No. 2 and \ dram (2 c.c.) of
No. 1, with Water 1 ounce (30 c.c).
ONE SOLUTION METOL-HYDROKINONE.*
Metol 20 grains 1 gramme
Hydrokinone 60 „ 3 grammes
Sodium Sulphite (cryst.) ... 700 „ 35 „
Sodium Carbonate (cryst.) ... 700 ,, 35 ,,
Potassium Bromide 6 0-3 gramme
Water to 20 ounces 500 c.c
Dissolve in the order given, allowing each chemical to be in complete
solution before adding the next. In well-stoppered bottles this developer
keeps almost indefinitely. For use dilute with an equal quantity of water.
N.B.—All metol-hydrokinone developers should be used at a temperature
of from 60° to 65° Fahr. Below 60° Fahr. hydrokinone rapidly loses its.
developing power and in very cold solutions becomes practically inert.
* Before making up any formula, read the notes on pages 125, 126 and 134.
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