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Artesian Wells. 



1 8. A vacuum may be formed by sucking the air from a 

 small glass bottle, and the effect of the pressure of the 

 surrounding air will be felt on your lips or tongue, perhaps 

 painfully: and, if the glass be very thin, that pressure 

 may crush the bottle. 



Artesian Wells : A, A, A, Rock or clay which, water cannot 

 penetrate ; B, B, Seams or Strata in which. Subterranean 

 Streams flow; C, Subterranean Reservoir filled with Water 

 by Rains ; D, D, Boring-s in the Ground or Rock. 



19. A piece of leather, soaked in water and pressed 

 down on a smooth pavement, adheres tightly to it by the 

 pressure of the air on it. In this case a vacuum is formed 

 between the leather or sucker and the pavement. 



20. In some places men bore deep holes in the rock or 

 ground, from which the water spurts up like fountains. 

 Such are called Artesian Wells. They are not dug like 

 common wells, but are drilled by long, sharp bars of iron 

 or steel, about as thick as a man's arm. 



