Popular Science Movtiih/ 



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and which are distributed tlirough the water in the pipe. The greater weight of water la 

 the well overbalances the aerated water, and is forced upward and discharged 



One or more wells are sunk to a depth 

 considcrahly below the level of the 

 underground water. A pipe of large 

 diameter open at the bottom is then 

 sunk nearly to the bottom of each well. 

 This is for the water discharge. When 

 not pumping, the water in this pipe 

 will be at the same level as that in the 

 well. A second pipe of small diameter 

 is also sunk to the bottom of each well, 

 terminating in a chamber which sur- 

 rounds the water-pipe. Air passes from 

 this chamber through small perforations 

 into the water-pipe, mixing small bubbles 

 with the water, giving a "champagne 

 effect." These bubbles rise very slowh', 

 until they arc distributed throughout 

 the entire column of water in the dis- 

 charge pipe. Coincident with the ad- 

 mission of air, the column of water 

 elongates until it discharges. 



The weight of water in the well over- 



balances the very much longer column 

 of aerated water in the pipe. Thus 

 the well-water flows into the discharge 

 pipe, is aerated and in turn discharged. 



The air pressure must be greater than 

 the water pressure at the bottom of the 

 well. Otherwise the water would force 

 its way into the air-pipe and stop 

 operations. 



The water may be lifted vertically 

 into a tank or reservoir or may be dis- 

 charged into a "booster" and then 

 carried horizontally. The booster is 

 simply a vessel which permits the air 

 and water to separate. 



In the air-lift system there are abso- 

 lutely no working parts, .such as pistons, 

 \alves, etc., under ground, which are 

 liable to wear, to rust, or to become de- 

 fective with use. Air is supplied by an 

 air-compressor, which ma>- be located 

 far from the wells, if desired. 



