PRINTING-OUT PAPERS 175 
Gelatine 127 g 975 gr. 
Water 500 ccm 8 oz. 
B. Silver nitrate 30.6 g Zao: 
Water 500 ccm 8 oz. 
Dissolve the tartaric acid in a little water, and neutralise with 
sodium carbonate; then mix as above. Very fast and vigor- 
ous printing, and suitable for both baths. 
V alenta.— 
A. Amonium chloride . 2.82 21.5 or 
Gelatine 96 g 737 gr. 
Water 750 ccm 12 oz. 
B. Tartaric acid 2.8¢ 21. S.en: 
Sodium bicarbonate 14¢ 10.75 gr. 
Alum 18¢ 13.8 gr. 
Water 125 ccm 202: 
C. Silver nitrate 32 g 245 gr. 
Water 125 ccm 2'0z. 
Citric acid 8g 61 gr. 
Dissolve the tartaric acid and the alum in the water, and add 
mee soda... Fleat ‘A and B to 50° C. (1227 F.), and add €, 
heated to the same temperature, slowly with constant stirring. 
Vigorous, rapid printing, suitable for both baths. 
All the above emulsions can be made much faster printing 
by allowing them to stand about 1 hour at the mixing tem- 
perature before coating. These emulsions give glossy sur- 
faces, when coated on glossy baryta paper. If matt surface 
papers are required, the quantity of gelatine should be re- 
duced by about one-sixth, and a matt surface paper used for 
the raw stock. A very good matt surface can be obtained 
by the addition of an ammoniacal solution of pale yellow 
resin, made as follows: 
Ammonia 20 ccm 153 min. 
Water 80 ccm 615 min. 
