SA EDP AUPE 197 
Citric acid 50 ¢ 384 gr. 
Water 1000 ccm 16 oz. 
Clean brilliant negatives and short exposure to a bright light 
are required; enlargements may also be made. After expo- 
sure the material should be immersed in a 5 per cent solution 
of ammonium chloride, and developed with: 
Pyrogallol 25.2 19 gr. 
Hydrochinon Taye 58 gr. 
Citric acid 10g 1/ gt. 
Sodium sulphite, dry 34 ¢ 260 gr. 
Water 1000 ccm 16 oz. 
Temperature 35° C. (95° F.). As soonas the image has well 
appeared, fix in an acid bath, and tone with gold. 
For an emulsion for fabrics, either of the following may 
be used: 
Hard gelatine 120g 2oz., 47 gr. 
Water 1300 ccm ZO78 
Dissolve, and add: 
Zinc bromide, cryst. 43 ¢ SoZ on: 
Cadmium iodide lg Ae os a 
Cadmium chloride 3¢g 23 gr. 
Next, add at\70° C. (158° F.): 
Alcohol 500 ccm 8 oz. 
Then add in the darkroom: 
Silver nitrate 50 g 384 gr. 
Water 100 ccm 770 min. 
Finally, add: 
Alcohol 100 ccm 770 min. 
Digest for 214 hours at 80° C. (176° F.), and then cool 
down with constant stirring until the temperature is 15° C. 
(69; F’.), when the emulsion will sink to the bottom of the 
vessel ; this should be collected, washed, and melted with the 
addition of: 
