ILLUSTRATIONS. 
Page. 
Fig. 1. Glass jar employed by Fittbogen (1873) in measuring the water require- 
ment of plants 12 
2. Pot employed by Kiesselbach and Montgomery (1911) in measuring the. 
water requirement of corn 21 
3. Apparatus used by Lawes (1850) in measuring the water requirement of 
plants 32 
4. Apparatus used by Von Seelhorst (1902) in his later measurements of 
the water requirement of plants 68 
5. Pot used by Briggs and Shantz (1913) in measuring the water require- 
ment of plants 80 
6. Sketch showing device used by Briggs and Shantz (1913) in adding 
water to the pots 80 
2S5 
