SALTED) PAPRR Ot 
tion, and the mixture boiled until it has dissolved, or not less 
than 2 hours, water being added from time to time to replace 
that which boils away. Then take: 
Bleached lac 50 g 384 gr. 
Sodium phosphate 25g 192 er. 
Water 750 ccm Zou: 
Boil in the same way as above, mix the solutions, and add: 
Gelatine 46 ¢ eS) ie. 
Water 500 ccm 8 oz. 
Allow the gelatine to soak in the water for 30 minutes, and 
melt by heat. Filter the mixture through fine linen. Im- 
merse the paper for 2 minutes, and hang up to dry. When 
nearly dry, again immerse, and hang up by the opposite end. 
To salt this, float the paper on: 
Ammonium chloride 23 g 177 gr. 
Magnesium lactate 23 g 177 gr. 
Water 1000 ccm 16 oz. 
Then hang up to dry. Either the borax-lac or phosphate-lac 
may be used alone with half the above quantity of gelatine 
solution. 
All plain papers are most satisfactorily sensitised by brush- 
ing the silver solution on, not floating. Either a plain silver 
solution may be used, such as: 
Silver nitrate 62.5 ¢ 1 oz. 
Water 500 ccm 8 oz. 
Or an acid one: } 
Silver nitrate 732 560 gr. 
Citric acid ay) fe 400 gr. 
Water 500 ccm 8 oz. 
Or an alkaline one: 
Silver nitrate 32 g 245 gr. 
Ammonia q. S. qs: 
Water 250 ccm 4 oz. 
