176 



EXPOSED WATER AND FRESHLY FALLEN RAIN 



The only known difference between the water in the cultures A 

 and B is a difference of radioactivity, that of the water collected one 

 month previous to the experiment probably being nearly or quite 



Days 



Fig. 43. Relative growth of Roots of Lufinus albtis in fresh Rain-Water and in 

 Rain-Water one month old. Culture B, Exp. 53. Cf. figure. 44. 



zero. It therefore seems a conclusion warranted by the conditions 

 of the experiment that freshly fallen rain-water tends to retard the 



28 

 24 



20 



16 



12 



8 



4 











10 



40 



50 



20 30 



Hours 

 Fig. 44. Relative growth of Roots of Lnpinus albus in fresh Rain-Water and in 

 Rain-Water one month old. Culture A, Exp. 53. Cf. figure 43. 



growth of roots of Ljipinus albiis, and that this effect is due to the 

 radioactivity of the water. 



