BOTANICAL PHOTOGRAPHY 185 



B 



Water 640 c.c. (16 oz.) 



Sodium sulphite (dry) 60 g. (2 oz.) 



C 



Water 640 c.c. (16 oz.) 



Sodium carbonate (dry) •SO g. (1 oz.) 



Mix 1 part of each of the three solutions and 8 parts of water. 

 Developer for line work (Cramer). — 



A 



Metric Apothecaries'- 



Avoirdupois 



Water 1,000 c.c. ( 32 oz.) 



Hydrochinon 45 g. ( 1^ oz.) 



Sodium sulphite 30 g. ( 1 oz.) 



Sulphuric acid 4 c.c. ( 60 minims) 



B 



Water 1,000 c.c. ( 32 oz.) 



Sodium carbonate 30 g. (1 oz.) 



Potassium carbonate 90 g. (3 oz.) 



Potassium bromide 8 g. (120 gr.) 



Sodium sulphite 90 g. (30 oz.) 



Use equal parts of A and B. This is good for maps and graphs and 

 also for lantern slides where considerable contrast is desired. 

 Land's Contrast Developer for negatives and lantern slides. — 



Hydrocliinon 20 g. 



Sodium sulphite (dry) 60 g. 



Sodium carbonate (dry) 140 g. 



Potassium bromide 12 g. 



Water 1,000 c.c. 



If kept tightly stoppered, with no air space between the liquid and 

 the cork, this developer keeps almost indefinitely. When some is 

 taken out for use, the rest should be put into a smaller bottle, so that 

 there shall be no air between the liquid and the cork. 



Another formula, developed by Dr. Land to meet the trying condi- 

 tions of the tropics, is also useful for lantern slides. 



