27O FARM MACHINERY 



Pump pistons are usually provided with only one cap 

 leather for the piston. For high pressures more are 

 needed, and in the better makes of deep-well pumps the 

 pistons are provided with three or even four leathers. 



383. Pump regulators have a hydraulic cylinder at- 

 tached, into which the pump forces water when the con- 

 nection with the tank is cut off by a float valve. The 

 hydraulic cylinder is provided with a piston and a stuffing 

 box and a piston rod. Connection is made by a chain 

 to a quadrant on a weighted lever above the platform. 

 This lever is also attached to the pull-out wire of the 

 mill. All the water being forced into the hydraulic cylin- 

 der, enough pressure is created to pull the mill out of 

 gear. Safety valves are provided to prevent too great 

 pressures coming on the hydraulic cylinder, which might 

 cause breakage. 



384. Chain and bucket pumps. Chain pumps have the 

 pistons or buckets attached to a chain running over a 

 sprocket wheel at the upper or crank end, and dip in the 

 water at the lower. The buckets are drawn up through 

 a tube, into which they fit and carry along with them 

 the water from the well. The chain pump is suited only 

 for low lifts. 



Another type of pump similar to the above and some- 

 times styled a water elevator has buckets open at one 

 end, attached to the chain. These are filled at the bottom 

 and are carried to the top, where they are emptied. It 

 is claimed the buckets carry air into the water and this 

 has a beneficial effect. 



385. Power pumps are not used very extensively about 

 the farm except for irrigation and drainage purposes. 

 When the power is applied with a belt the pump is known 

 as a belted pump. If provided with two cylinders, it is 

 known as duplex; if three, triplex. The cylinders may 



