1*1 



intake of water by the plant end loss of water from f 

 reservoir. The effect of temperature is more important. 



! change in the surface tension of water with tem- 

 perature is shown in the following table. 



SURFACE MSI H Di WATER, 



Temperature Surface Tension 



(degrees C.t ( aifliiuiuo per centimeter) 



73.21 



10 71.94 



20 70.60 



SO 69-10 



40 67.50 



50 65.98 



80 60.84 



100 57.15 



TI 5ata are from Hamsey and Shields, by cap- 

 illary rise, Zeits. phys. Cham. 12: 433 (1893). For 

 other data, including data by other methods, see Landolt 

 and Bornstein, Physik,- Chem. Tab., 3rd ed., p. 113 (1912) 

 and Morgan and McAfee,- Jour. Amer. Chem. Soc. 33_: 1-75- 

 1290 (1911). For equations of relation of surface tension 

 to temperature see Landolt and Bornstein, loo , cit .. p. 

 131, and Morgan and McAfee, loo. cit ., p. 1283. A good 

 general discussion of surface tension will be found in 

 Freundlich,- Kapillarchemie, pp. 3-89 (1909). 



