Draining Sinks and Ponds 



463 



rapid growth and large evaporation of moisture 

 through the foliage, considerable amounts of water 

 will be removed. The most serious objection to the 

 method is the fact that the trees will not render their 

 greatest service early in the season, and may not fit 

 the ground for early crops other than grass. 



THE USE OP THE WINDMILL IN DRAINAGE 



In such places as those under consideration in the 

 last two sections, a good windmill may be made to 

 drain a considerable area of ground where only the 



Fig. 150. Method of draining sinks by wind power. 



underflow must be handled, and where the lift need 

 not be more than 20 feet. 



'If the water is to be raised to a level at which 

 gravity will remove it, then a sump or reservoir 

 should be sunk in the ground as near the place where 

 the water is to be disposed of as practicable, deep 

 enough to hold the drainage of two or three days 

 when, for lack of wind, the mill may be idle. 



In order that the mill may work during the winter 

 also in cold climates, the pump may be placed in a 



