TONING BROMIDE PRINTS 225 
Ammonium chloride 100 g 768 gr. 
Water 1000 ccm 16 oz. 
More ferric chloride gives bluer tones. Wash and fix in an 
acid-hypo sodium acetate bath. 
Leap Toninc.—Various colours may be obtained by 
bleaching prints with a lead salt and ferricyanide, and sub- 
sequent treatment with various reagents. The results are not 
very satisfactory; there is a very great tendency for the 
whites to be stained, and great intensification is given. The 
bleaching bath may be: 
Lead acetate or nitrate 40g 307 gr. 
Glacial acetic acid 100 ccm 770 gr. 
Potassium ferricyanide 60 g 460 gr. 
Water 1000 ccm 16 oz. 
When thoroughly bleached, the prints should be washed with 
three successive baths of 10 per cent nitric acid, then washed 
for a short time with water, and treated with one of the 
following baths: ammonium sulphide, 1:3, for black; 
Schlippe’s salt, 2 per cent solution, for reddish-yellow; 
potassium chromate, 2 per cent, for yellow; ferric chloride 
for green; cupric chloride for red; uranium nitrate and 
ammonium chloride for red-brown; cobalt or nickel chloride 
for green; mercuric iodide for orange-yellow. 
Lead-tron for greenish tones (Maquenne).—This is a com- 
plicated process, which is open to the same objections as 
above, but the prints must be rather denser than normal, as 
there is no intensification. Four stock solutions are required, 
which will keep in the dark: 
A! Lead acetate 135 ¢ 1036 gr. 
Glacial acetic acid 100 ccm 768 min. 
Ferric chloride, dry Los 115 gr. 
Water 1000 ccm 16 oz. 
B. Lead acetate 100 g 768 gr. 
