106 FARM MECHANICS 



pumps and engines. Centrifugal pumps usually are 

 set in dry wells a few feet above the water-table. While 

 these pumps have a certain amount of suction, it is 

 found that short supply pipes are much more efficient. 

 Where water is found in abundance within from 15 to 

 30 feet of the surface, and the wells may be so con- 

 structed that the pull-down, or the lowering of the 



Figure 119. Centrifugal Pump. This style of pump is used in 

 many places for irrigation. It runs at high speed, which varies 

 according to the size of the pump. It takes water at the center and 

 discharges it at the outside of the casing. 



water while pumping is not excessive, then it is pos- 

 sible to lift water profitably to irrigate crops in the 

 humid sections. Irrigation in such cases, in the East, is 

 more in the nature of insurance against drouth. Valu- 

 able crops, such as potatoes and strawberries, may be 

 made to yield double, or better, by supplying plenty 

 of moisture at the critical time in crop development. 

 It is a new proposition in eastern farming that is likely 

 to develop in the near future. 



