Mills driven by the wind

August 22, 2011

alt src=http://www.tehrantimes.com/images/stories/iranhighlighs/windmill%201.jpgSince early recorded history, people have been harnessing the energy of the wind. Wind energy propelled boats along the Nile River as early as 5000 B.C.
The earliest known windmill design dates far back in time when Iranians grinded grain and pump water.
The first practical windmills were fitted with sails that rotated in the horizontal plane around a vertical axis. These were invented in Eastern Persia (What is now modern day Afghanistan). The Persian geographer Estakhri recorded these in the 9th Century AD.
Made of six to twelve sails covered in reed matting or cloth material, these windmills were used to grind grain or draw up water, and were quite different from the later European horizontal-axis versions.
There is said that the second Caliph Umar (AD 634-644) was using a windmill in around the 7th century, however this is disputed due to the fact that this anecdote appears in a 10th century document.
A type of windmill with rectangular blades, believed to have been used for irrigation, is also found in 13th Century China during the Jurchen Jin Dynasty in the North. Apparently this design was introduced to the area known as Turkestan around 1219 through the travels of Yelu Chucai a prominent traveler and historian of the time.
These Persian windmills were generally constructed with six to twelve sails which would have been covered in matting made from reeds or cloth material. The predominant uses for these mills was the grinding of corn and drawing up of water. These mills differed much from the later European vertical windmills.
From these early wind machines the windmill evolved over the centuries and spread far and wide across the globe originally across the Middle East and Central Asia and then later into Chine and India and from there on to the rest of the world.
Windmills appear to have reached England in or around the 12th Century and it’s believed that the knowledge of these “wind engines” came back with the Crusaders, certainly there are ruins of windmills in Northern France that date from around that period.
In later centuries the Dutch seem to have become the “windmill experts” of Europe and many of the later windmills such as Fan-tails and the like are accredited to Dutch designers and engineers along with some truly innovative advancements in windmill sail technology.                                                                     (Source: outwoodmill.com)