132 



AGRICULTURAL ENGINEERING 



Fig. 72. A canvas dam in use. (Farm- 

 er's Bui. 392, U. S. Dept. of Agr.) 



low, flat levees, or ridges. 

 Into these checks the 

 water is turned. On level 

 ground these sections or 

 checks may be made rec- 

 tangular; but on sloping 

 ground the ditch for sup- 

 plying the water must fol- 

 low the contour lines, in 

 which case they are said 

 to be contour checks. 

 In applying the water, 



an opening is made from the ditch into the side of each 



check and the water 



allowed to flow in 



until each is covered 



to the desired depth. 



Where the check 



method is followed, 



it is customary to 



have small wooden 



outlets from the ditch 



into the checks, with 



Fig. 73. 



Check method of irrigation. 

 U. S. Dept. of Agr.) 



(Sep. 514, 



F<g. 74. Basin method of irrigation. (Sep. 

 U. S. Dept. of Agr.) 



valves which can be 

 operated to close the 

 opening when de- 

 sired. 



Basin Method. 

 The basin method is 

 quite similar to the 

 check method. It 



is used principally 

 in the irrigat j on O f 



