PRINTING-OUT PAPERS 185 
Water 1000 ccm 16 oz. 
B. Potassium bromide 62.5 ¢g Loz: 
Ammonia 9 ccm 70 min. 
or Sodium carbonate, cryst. 45.5¢ ° 350gr. 
Water 1000 ccm 16 oz. 
For use mix 1 part of each with 1 part water. Or the follow- 
ing may be used: 
A. Hydrochinon 3.65 g 28 gr. 
Sodium sulphite, dry 3.65 g 28 gr. 
_ Water 1000 ccm 16 oz. 
For use, mix 4 parts A, 4 parts B, given above, and 8 parts 
water. Greater contrasts can be obtained by decreasing A to 
3 parts, while flatter prints can be secured by increasing A to 
7 parts, the water in each case being increased or reduced, so 
as to make the total bulk of the solution the same. Another 
formula (Kodak) is the following: 
A. Hydrochinon 7.32 56 gr. 
Sodium sulphite, dry 3.65 g 28 gr. 
Potassium bromide 14.6 ¢ 112 er. 
Ammonium bromide 2926 224 er. 
Water 1000 ccm 16 oz. 
B. Caustic soda 62.5 ¢ 1 oz. 
Water 1000 ccm 16 oz. 
C. Tannin 16.6 g 128 gr. 
Water 1000 ccm 16 oz. 
For use mix 150 parts A, 30 parts B, 4 parts C. 
Whichever developer be used, it is important to observe the 
greatest care not to expose the paper to white light, as the 
slightest light action is developed. It is, therefore, advisable 
to manipulate the paper by yellow light entirely. The image 
should only be faintly visible after exposure. After the 
bromide bath, the prints should be washed at least 3 minutes. 
The developed image is a pale yellow or orange colour; care 
