350 PHOTOGRAPHIC FACTS AND FORMULAS 
the sulphite and bromide. When the solution is cold add the © 
ammonia. For use mix 1 volume with 3 of water and use at 
18° C. (65° F.). Development time, 3 minutes. Then rinse 
slightly and immerse in the following reversing bath: 
Potassium bichromate 5¢ 38 gr. 
Sulphuric acid 10 ccm 77 min. 
Water 1000 ccm 16 oz. 
The plate may now be handled in daylight and after about 3 
minutes in this bath it should be washed for 30 seconds and 
reimmersed in the developer for about 2 minutes. Then 
wash in running water for 3 minutes. Drying should be 
effected in a warm place, but not by heat. The plate may be 
varnished by gently heating first and then coating with 3 per 
cent solution of gum dammar in benzole. 
a _ 
