Early European windmills turned their whole body to catch the wind
Winds in northwestern Europe shift constantly, so the region's first windmills were balanced on a single massive upright post. Millers heaved the entire wooden building, machinery and all, around to face each new breeze. Later designers learned to rotate only the cap, and eventually a tiny rear windmill did the turning automatically.
Europe's earliest certain windmill reference dates from 1185, at the vanished village of Weedley in Yorkshire, overlooking the Humber Estuary. These sail-in-a-vertical-plane mills appeared in the 12th century in a triangle spanning northern France, eastern England and Flanders, and they ground cereals. Whether they owed anything to the very different Persian windmills that had reached southern Europe a century earlier remains unclear.
Persia had led the way. Its panemone, invented sometime between about 700 and 900 AD, spun six to twelve sails of reed matting or cloth horizontally around an upright shaft, first to pump water and later to grind grain. The geographer Estakhri reported windmills working in Khorasan in the 9th century. The design spread across the Middle East and Central Asia, reached Iberia and the Aegean by the 11th century, and appeared in 13th-century northern China after Yelü Chucai travelled to Turkestan in 1219.
The European post mill came first. Its early versions had the post sunk into an earth mound; later a wooden trestle, often enclosed in a roundhouse for storage, held it up. Hollowing the post to carry a drive shaft let mills power machinery below, and from the early 15th century Dutch hollow-post mills drove scoop wheels to drain wetlands. By the end of the 13th century, masonry tower mills had arrived. Only their caps rotated, so the towers could rise higher and carry longer sails that worked in light winds, though they cost more to build.
A fantail, a small windmill mounted at right angles behind the sails, kept the cap facing the wind without human help. In the 17th century the Dutch introduced the smock mill, with a brick base and a sloping, usually eight-sided wooden upper frame, light enough to stand on soft, wet ground where heavy stone towers could not. Post mills remained Europe's most common type until the 19th century.
Source: Windmill
