286 



The Plant World. 



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Fig. 2 



Fig. 1. Diagram of the Piche Atmometer. R, graduated glass reservoir; D, absorbent 

 paper disk; F, metal clip about reservoir; W, metal spring; C, metal disk holding paper in 

 place. 



Fig. 2. Diagram of the Cantoni Piche Atmometer. R, graduated glass reservoir (burette); 

 T, Supply tube from higher reservoir, for filling burette; P, pinch cock; E., tube supplying 

 the evaporating surface; D, absorbent paper disk; F, cork ring on tube E; W, metal spring; 

 C, metal disk holding paper in place. 



Fig. 3. Diagram showing mounting of the paper cylinder, the rest of the instrument as in 

 Fig. 2. E, tin tube; D, Paper cylinder; L, cork wedges to hold lower edge of cylinder in 

 place; S, tin seat; F, cork ring on tube E; V, metal spring, flexed by W, fine wire; K, ce- 

 ment holding V to C, concave glass cap, wliich presses upon closed end of cylinder, holding 

 It in place 



