464 



Introduction to the Study of Science 



What do the results show? How much water is lost in a day? 

 Does it seem to depend upon the temperature of the room where the 



plant is kept? Does it vary 

 by day and by night ? 



The same fact may be shown 

 with the apparatus illustrated 

 in Fig. 148. Select a stem or 

 shoot that is fresh and plenti- 

 fully supplied with leaves. See 

 that the corks fit close to pre- 

 vent escape of water except 

 through the branch. Mark the 

 place the water reaches in the 

 tubing. Set the apparatus in a 

 good clear light. 



Table of materials used by 

 plants. The quantities of 

 materials that plants remove 

 from the soil, the amount of 

 soil water utilized and re- 

 leased through transpiration 

 and evaporation, and its 



FIG. 148. Arrangement of apparatus to equivalent in inches of rain- 

 show transpiration. -,-, -, . . , 



fall, are presented in the 



following table, 

 per acre. 



The crops are expressed in bushels or pounds 



