Reducers 
PoTASSIO-FERRIC OXALATE (Belitzski)—A very conveni- 
ent reducer, which may be kept as a stock solution in the dark, 
and repeatedly used until it turns yellow, which is a sign of 
exhaustion: . 
Potassium ferric oxalate 50 g 384 gr. 
Water 1000 ccm 16 oz. 
Dissolve, and add: 
Sodium sulphite, dry 20 g 154 gr. 
This forms a blood red solution, to which should be added: 
Oxalic acid, cryst. I5¢ 115 gr. 
Shake the solution until a bright green colour is formed, free 
from any tinge of yellow; then pour off from any undissolved 
crystals, and add: 
Hypo 250 g 4 oz. 
Shake until dissolved. 
It is preferable to soak the negative in water before apply- 
ing the reducer. Thorough washing should follow the reduc- 
tion. Instead of the potassium ferric oxalate, the following 
may be used: 
Ferric chloride 32:52 500 gr. 
Neutral potassium oxalate 62.5 ¢ 950 gr. 
This will make the above quantity of potassium ferric oxalate, 
and the potassium chloride formed is negligible. The reducer 
tends to attack the shadows more than the high-lights, there- 
fore, increases contrasts. 
HyYpocHLoritE AND ALumM (Debenham).—An excellent 
reducer, which can be locally used by immersing the negative 
in the solution and rubbing any part with a pad of absorbent 
cotton : 
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