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Mill Power

Windmills are believed to have first appeared in Persia in about the 7th Century AD.
They were unknown in Britain until the end of the 12th Century, when the idea
was brought to northern Europe by the Crusaders. They proved useful in flatter areas such as the Netherlands, East Anglia and Lincolnshire, where there are few swiftly-flowing rivers suitable for driving a water-mill.

Where farmland was being reclaimed from marsh-land or the sea, the principle was used to pump water ... indeed, if you see a working windmill of the traditional
pattern in the Netherlands today, it's more likely to be a wind-pump.

Early windmills were fixed structures, such as those seen in the Greek islands. There are two main types of windmill here; the horse-shoe mill had a D-shaped plan, with the sail always on the rounded side. Round mills are a later innovation. They were often built in groups, and the miller selected the one whose sails were set closest to the wind!

This isn't a very satisfactory arrangement, and ways were devised to ensure that the sails always faced into wind. Most surviving windmills are stone- or brick-built
mills called cap or tower mills. Only the cap of the windmill rotates to turn the sails into wind.

A post mill needed the entire structure rotating by hand. Some tower mills were built of wood, and called smock mills, because of a fancied resemblance to a countryman in a smock.

Earlier smock and tower mills required the cap to be turned by hand, using a tail-post, as many continental windmills still do. But, in 1745, the fantail was patented in England. This is the secondary rotary vane which automatically rotates the cap.

Until 1772, all windmills had common sails. This is simply a framework to which canvas is attached. Like the sail of a boat, this can be reefed or furled, depending upon the wind velocity ... probably why, like a ship, a windmill was frequently referred to as she'.

Andrew Meikle invented sails where canvas was replaced by wooden shutters, which
opened automatically if the wind reached a certain speed. This ensured the machinery turned at a constant rate. In 1807, William Cubbitt developed the patent sail, which allowed adjustments to be made without the need to stop the mill.

The sails turn at about 15 rpm., transmitting power through a right angle to the main
shaft, turning at double that rate. The speed is doubled again at the one-ton millstones.

The miller's life was often lonely. The mill was usually in an exposed position, maybe some

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