INTENSIFICATION 139 
A. Quinone 5g 38 gr. 
Potassium bromide 25) 2 192 gr. 
Water 1000 ccm 16 oz. 
Or: 
B. Sodiumquinone sulphonate 10g 77 ox: 
Potassium bromide 25 ¢ 1 Zion: 
Water 1000 ccm 16 oz. 
The negative after treatment may look muddy. It should be 
briefly rinsed with water, and immersed in a 10 per cent 
solution of ammonia. The colour given by A is reddish 
brown, by B yellowish brown. Ammonia, with short action, 
gives great intensification, both images becoming dark brown; 
after 10 minutes’ action, the original colours are again formed 
with less intensification. The carbonates of sodium and 
potassium also turn the images brown, giving also great in- 
tensification. Hypo reduces the image without altering the 
colour of plates treated with A, but with B the final colour 
is a reddish-yellow. Sulphites or bisulphites convert the 
image of A into a greenish-brown; in the case of B, into a 
dark brown. An amidol developer acts like sulphite on A, 
but gives yellowish-black images with B. 
Bromo-Iop1pE oF Copper (Jenney).— 
Cupric sulphate 37.5 288 gr. 
Water 500 ccm 8 oz. 
When dissolved, add: 
Potassium iodide og 69 gr. 
Potassium bromide 23g LL eK. 
Water 500 ccm 8 oz. 
A slight precipitate of copper iodide is formed, which should 
be filtered out. The negative should be immersed in the solu- 
tion until bleached to a bright yellow colour, which takes 
from 5 to 15 minutes, and then well washed and immersed 
in a saturated solution of sodium sulphite to which a few 
