THE 1RR1 GA Tl ON A GE. 



281 



charged at the openings shall be nearly equal. The openings are 

 simply cuts in the side of the ditch, each one supplying several fur- 

 rows, and divided with hoed or shoveled ways in the earth. If the 

 flume is used, the water is taken out through holes bored at proper 

 intervals in the sides, and if the slope along the line of the flume is 

 too rapid, the lengths of the flume are leveled and "drops" arranged 



^f^^^^^ff^-'^^^ 



PJG. 17. Furrow irrigation on a slope with stepped flumes and drop. 



for the water from one length to the next. Thus a series of flume 

 lengths, each one level, may be carried down quite a slope by steps 

 (Fig. 17), and give equal discharge of water for all the furrows of a 

 wide field. 



There are very many ways by which water may be brought to the 

 heads of the furrows, such as movable troughs, canvas hose, etc., ac- 

 cording to the local conditions and the ingenuity of the operator. If 

 the soil is not too porous, the furrow method is a good recourse when 

 a small stream of water running continuously has to be used; for it is 

 easy to arrange so that attention need to be given to it only at inter- 

 vals and the irrigator can proceed with his other work. 



This furrow irrigation operates on a flat culture basis. As soon 

 as the ground dries sufficiently a cultivator is used between the rows 

 and the ground leveled and pulverized as thoroughly as possible to 

 prevent surface evaporation and baking of the soil. When another 

 irrigation is needed new furrows are made as before. 



(To be continued.) 



