IRRIGATION 



75 



located along the sloping border of a lake ; the water 

 is procured from flowing wells located at the upper 

 side of the slope. Leading from the higher ground 

 toward the lake are wooden flumes set into the 

 ground to a depth of about 12 inches. Nearly every 

 20 feet along the flume there are openings into lines 

 of three-inch drain tiles laid practically on a level 



FIG. 30 PLAN OF SUBIRRIGATION SYSTEM AS EMPLOYED IN FLORIDA 

 A, well; B, head flume; C, distributing flumes; D, open ditch; E, sub- 

 irrigation tiles; F, sluice gates; G, check gates 



across the slope and at right angles to the flume. 

 The opening into the tile is controlled by means of 

 a slide which is raised for the admission of water. 

 A few inches below the opening into the tile is 

 located a check board which does not extend to the 

 top of the flume, but serves to back the water into 

 the tile and permit the surplus to flow over and 



