130 



IRRIGATION FARMING. 



entirely for regulating the flow of water; but a step 

 in advance is made by putting in wooden boxes at 

 such places, with a simple gate board sliding between 

 upright cleats. In this way the exact quantity of water 

 desired may be diverted, without danger that too much 

 will force its way through. One advantage of these 

 subsidiary canals is that ifc catches up the leakage of 

 the main canal and utilizes it for immediate use, and 

 at the same time avoids the discomfitures of seepage 



FI<;. 43. LATKKAL lil/LKIIKAI). 



waters on the lands to be irrigated. Sometimes these 

 secondary canals are cemented, and they are useful 

 in governing the water for the furrows by means of 

 bulkheads. These bulkheads may best be fixed perma- 

 nently in position, and if supplied with sluice gates tin-\ 

 are ready for use at all times, and will last for years. "Fix 

 these boxes in the lower bank of the subsidiary ditch at 

 the head of the laterals and they may also be used in 



