106 PHOTOGRAPHIC FACTS AND FORMULAS 
Eastman X-Ray Film.— ; 
Elon (metol) 2/72 40 er. 
Sodium sulphite, dry 120 g 4 oz. 
Hydrochinon llg 160 gr. 
Sodium carbonate, dry 60 g 2 Oz. 
Potassium bromide ZL e 32 gr. 
Water 1200 ccm 40 oz. 
The above is for tray development ; for tank, use: 
Elon (metol) 42g 1loz.,240 gr. 
Sodium sulphite, dry 2040 g 68 oz. 
Hydrochinon 185g 60z2., 96 gr. 
Sodium carbonate, dry 1020 g 34 oz. 
Potassium bromide 36 g 550 gr. 
Water to 22000 ccm 6 gal. 
Hammer Postal Plate—Stock solutions : 
1. Metol 2/72 165 gr. 
Hydrochinon 10g LY, oz. 
Sodium sulphite 38 g 6 oz. 
Water 1000 ccm 128 oz. 
2. Sodium carbonate 78g 10 oz. 
Water 1000 ccm 128 oz. 
For use mix equal parts of Nos. 1 and 2. 
One solution developer : 
Metol 0.15 g 22Y4 gr. 
Hydrochinon 0.30 g 45 gr. 
Sodium sulphite 12 ¢ 34 OZ. 
Sodium carbonate 4g Y4 oz. 
Potassium bromide 0.4¢ 6 gr. 
Water 1000 ccm 32 oz. 
For use mix with an equal volume of water. 
Rexo Film.—Dissolve the chemicals in the following order : 
Metol b25'¢ | 20 gr. 
Sodium sulphite, dry 14g Y, oz. 
