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necessary first to provide a reservoir; little can be 

 done with the small stream pumped direct from 

 the well. The storage reservoir or tank may be 

 of wood or other material, but usually the most 

 practicable method is to build one of earth as 

 already described. Sometimes two or more mills 

 are placed around a reservoir of this kind. 



Steam and Gasoline Engines. This power is 

 used chiefly by market garaeners in the East for 

 irrigating small areas, when the height to which 

 the water must be raised is not over 20 feet. There 

 are many makes and styles of engines adapted for 

 this purpose. Gasoline engines are commonly 

 used when coal and wood are very costly. A 

 2-horse-power gasoline engine should irrigate an 

 acre at a cost for fuel of about 50 cents a day. 

 The cost of pumping water by engines usually 

 exceeds the cost of maintaining ditches or the price 

 of water bought from a canal company. King 

 found that a 2^-horse-power gasoline engine could 

 pump sufficient water to cover an acre 12 inches 

 deep for $3.75 per acre, and that it could easily 

 irrigate 10 acres 12 inches deep without a reservoir. 

 The same authority determined that an 8-horse- 

 power portable engine, with soft coal at $4 per ton 

 and with a lift of 26 feet, could draw water through 

 110 feet of 6-inch suction pipe and discharge it 

 through varying lengths of the same pipe up to 

 1,200 feet at a fuel cost of 18.1 cents per incn of 

 water per acre, or $2.17 per acre for 12 inches. 

 The expense of pumping is rarely below $3 an 

 acre per season, and often twice or thrice that 

 amount. 



Gasoline pumps range in capacity from 5,000 

 gallons per minute from a depth of 25 feet down to 

 300 gallons per minute. Centrifugal pumps run 



