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A History of Windmills
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Windmills
have been around for a very long time. The first windmills were
used to grind grain and then to pump water. Today they are also
used to make electricity. These windmills are called wind turbines.
The first windmills were invented in Persia around 600 A.D.
to grind grain. Built like a merry-go-round with the blades
standing up around a vertical shaft, they looked very much like
a water wheel turned on end. The problem was that without the
wind hitting only one side of the windmill, it would not spin.
To direct the wind to only one side, walls were built around
the windmill with a slot-shaped opening on one side. The Chinese
discovered that if you set the blades at an angle to the shaft,
the mill would spin continually without the walls around it.
By the 1100s, windmills had spread throughout Europe. About
this time, it was discovered that windmills had more power when
the sails or blades turned on a horizontal shaft, like the great
Dutch windmills that used four blades and could pump large amounts
of water. Over time, windmills began to be built bigger and
became more ornate. In fact, some even became homes for the
millers who owned and worked in them.
During
the 1970s, shortages of oil for generating electricity led to
interest and research in wind power. By the early 1980s, advances
in technology had made it possible for wind turbines to produce
large amounts of electricity. Some states, like New York and
California, installed thousands of the new wind turbines, which
are still in use. Windmills are perhaps one of the future answers
to generating electricity. Please e-mail
the professor your history ideas.
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