220 



Plant Physiology 



Set up the experi- 

 ment about as shown 

 in Figure 58. Ar- 

 range netted wire 

 If support (C), funnel 

 IU (B), and plant in 

 position. (Why so 

 much distance be- 

 tween (B) and walls 

 of vessel (A)?) The 

 water in the battery 

 jar should more than 

 cover the stem of the 

 funnel. Arrange the 

 series of tubes with 

 rubber connections 

 and pinch-cocks as 

 shown, but fill the 

 series with water and 

 place the finger over 

 (D) before inversion 

 over the funnel. 

 Support the series 

 by the clamp. As 

 the bubbles of gas 

 come off they will be 

 caught in (F), dis- 

 placing water. The 

 experiment should be 

 set in fairly bright 

 light until about two 

 inches of water are 

 displaced. 



When sufficient 

 gas is caught, note 

 the displacement, or 

 FIG. 58. Apparatus for the determination of mark accurately with 



oxygen release in photosynthesis. 



a label. The gas 



