CEMENT IN IRRIGATION 



201 



which too deep use of the subsoiler has admitted the water at 

 a point too low for best results to the tree which grows on a leachy 

 subsoil, and the cutting- of roots by the subsoiler has in some cases 

 brought shallows-rooting trees into temporary distress. The gen- 

 eral conclusion, however, is that deeper introduction of water favors 

 deeper rooting and is very economical of water by preventing the 

 loss by evaporation from the surface, which, theoretically, is dry, 

 but which actually, with shallow furrows over an irrigation hard- 

 pan, becomes too often saturated over nearly the whole space 

 between the trees. 



Continuous cement flume with weirs to raise water to outlet tubes. 



Cement Pipes and Flumes for the Furrow System. The use of 

 cement in the construction of flumes has largely increased because, 

 by means of locally devised machinery, continuous cement flume 

 has been cheapened so that its first cost is less than that of lumber 

 flume where suitably durable lumber is high. Similar machinery 

 is used for the construction of continuous cement pipe, which is 

 replacing open laterals in carrying water from main ditches to 

 the land of individual irrigators. This pipe is made by a machine 

 constructed by two Riverside men who are both machinists and 

 practical orchardists. Sand and barrels of cement are distributed 

 along the line ahead of the machine, as shown in the background 

 of the picture. The mixing is done in flat boxes, each being 

 carried forward when emptied. One of the lines of large rubber 



