122 



DOMESTIC WATER SUPPLIES FOR THE FARM 



an excavated pit from 5 to 10 feet in depth, afterwards filled in or 

 covered by a platform to prevent freezing. When the water is 



at greater depths the 

 pump cylinder must 

 be lowered inside the 

 outer casing until 

 within working dis- 

 tance of the supply. 

 The price of pitcher 



pumps ranges from $i to $2.50. Wooden suc- 

 tion pumps cost from $2.75 to $3.25, or, if 

 porcelain-lined, from $3.25 to $4.00. 



When suction pipes are used in connection 

 with open wells it is common to fit the bot- 

 tom of the suction pipe with a strainer and 

 "foot- valve" as an aid in preventing the re- 

 turn of the water to the well. Such a valve 

 is a great help in keeping the pump primed 

 and preventing the water from "running off." 

 A small hole is often drilled in the pipe above 

 the depressed cylinder to permit the water to 

 escape and prevent freezing. 



FIG. 51. Diagram of A s P ecial form of pump, provided with an 

 suction pump. S P, air chamber inserted between the pump-cylin- 



suction pipe; SV dcr and the we jj j g uged when the suction 

 suction valve; P V, 



plunger valve. pipe is very long for the purpose of lessening 



the strains. 



Deep Well Pumps. - - The term deep well pump is commonly 

 applied to any form of pump used when the water is below suction 

 depth (Fig. 53). In the smaller wells, which are usually of the 

 driven type and about 2 inches in diameter, a valve is set in the 

 pipe just above the screen and below water level, while the plun- 

 ger works in the casing itself immediately above the valve (Fig. 54). 

 In larger wells the pump-cylinder, with a suction pipe below and 

 a delivery pipe above, is lowered inside the casing. At times this 



