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A well is an artificial boring in the earth through which water can be
obtained.
different types of wells
Two classes may be distinguished:
- shallow or ordinary wells, sunk through a permeable stratum (aquifer) until an
impermeable stratum is reached; or
- deep and artesian wells, the latter
named from Artois in France, which are sunk through an impermeable stratum down into a
water-bearing stratum which overlies an impermeable stratum.
possible contamination
Obviously ordinary wells can supply water very cheaply, but, since impurities readily reach them, there is great risk of
contamination. The same does not apply to deep wells, such water being usually free from organic impurities. In ordinary wells,
and in deep wells, the water requires pumping to the surface; in artesian wells, on the other hand, the water usually spouts up
to a greater or less height above it.
history
The earliest wells are known from the Neolithic. In the submerged Pre-Pottery Neolithic
B settlement of Atlit-Yam in
Israel, dated to 8100--7500 BC, a well has been found, which so far is the oldest
known. Wood-lined wells are known from the early Neolithic Linearbandkeramic culture, for example in Kückhoven and Eythra in Germany and [[[Schletz]] in Austria. The early Mesolithic site of Friesack in Germany has yielded a shallow pit with the remains of a birch-bark container that may have been a
shallow artificial well as well.
- See also: oil well
external links
http://ancientneareast.tripod.com/Atlit_Yam.html
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