SOIL WATER 



323 



Experiment 96. Weigh out equal amounts (about 100 g. each) 

 of dried gravel, coarse sand, and very fine sand. Put each of these 

 into a four-inch funnel which has been fitted with a filter paper. 

 Pour water upon each until all that can be absorbed has been 

 absorbed. Allow each 

 to stand until water 

 ceases to drop from 

 the funnel. Weigh 

 again, balancing the 

 weight of the wet filter 

 paper retainer by a 

 similar wet filter paper 

 placed on the weight 

 side of the scales. 

 Which of these sub- 

 stances is capable of 

 holding the most water ? 

 Since water does not 

 penetrate into the 

 grains composing these 

 different substances the 

 difference in water- 

 holding capacity must 

 be due to the different 

 sizes of the grains. 



If we dig deep 

 enough into almost 

 any soil we shall find 

 water. Wells show 

 this. Certain trees 



and plants have such long roots that they can reach the 

 underlying water and flourish where other plants will die. 

 When wet lands are so drained by tiling that the plants 

 can send their long roots down to this constant water 

 supply or water table, as it is called, they stand a drought 



ALFALFA PLANT 

 The alfalfa roots go deep to seek water. 



