Jean Aliff, age 10, Fayetteville, WA.,
What is an artesian well?
Since earliest times, people have been digging to find precious water, Sometimes it would be a well tapped water that gushed forth like a natural spring. Some of the oasis in the dry Sahara sprang from such wells. In China, India and Iran there are traces which show that such wells date back to the dawn of history.
No one called them artesian wells until about 200 years ago. By that time the people of Western Europe had discovered a short cut to old time well digging, They were using drills and machines to drill for water. The French province of Artois was famous for these man‑made springs. Such wells were called artesian wells after the wells of Artois,
The wells, of course, are supplied with the rain water stored in the ground. Rainfall seeps down into the earth whenever it can. It trickles between cracks, seeps through sand and soaks into the pores of certain rocks. But not all the underground rocks have pores and cracks. Sooner or later the water reaches a dense, solid shelf of rock, It can sink and seep no further Here it comes to rest on a solid floor and forms the ground water.
Ground water breaks forth as springs to join the flowing rivers. It drips through the caves and fills up the lakes. In some places, it gets sandwiched in a bed of porous rock between crusty layers of dense rock, The rocky sandwich‑filling is often sandstone, The crusty top and bottom may be shale or granite. Sometimes the rocky sandwich dips to form a pocket This is a good place to start boring for an artesian well.
Boring tools, maybe diamond cutters, are used to drill the hole. The drill and pounding hammers are mounted on a derrick with a winding drum, The top layer of rock is hard and the drilling is tough. The borer drills through the top layer of the crust, deep into the layer of water‑logged sandstone below. If all goes well, the water comes gushing up through the boring tube.
Sometimes it keeps on gushing under its own power for many years. This is because of the surrounding water in the sandstone. The weight of this water presses down around the outlet: The pressure is sometimes great enough to push straight up to the surface a half a mile above. Not all wells have this amount of pressure. Their water must be pumped up by electric motors. Usually, we save the term artesian well for those that gush by themselves.
There are more artesian wells in the world than you might suppose. Many farms and isolated houses depend on their own artesian wells for water, The big city of London uses one and a half million gallons of artesian well water each day. The states of Kansas Nebraska Colorado and South Dakota draw much of their water from artesian wells. These vast underground reservoirs yield 125 million gallons of water daily and could yield much more. Texas, Montana California and New Mexico use artesian well rater to irrigate their farmlands,