Water and the Plant 89 



51. Pour gently and slowly a pint of water into the top of each 

 chimney. The water that drips through is free water ; that which 

 is kept has become capillary water. Compare as to time when 

 water begins to drip, length of time the dripping continues, and 

 amount of water retained. 



How does the addition of humus affect the water-holding 

 power of sandy soils? How does sand improve a clay soil? 



