Young Brunette Girl With Pubic Hair Landing Strip Posing In The Village With Old Wooden Windmills

• Smock mill
The smock mill is a later development of the tower mill where the tower is replaced by a wooden framework, called the "smock." The smock is commonly of octagonal plan, though examples with more, or fewer, sides exist. The smock is thatched, boarded or covered by other materials like slate, sheet metal or tar paper. The lighter construction in comparison to tower mills make smock mills practical as drainage mills as these often had to be built in areas with unstable subsoil. Having originated as a drainage mill, smock mills are also used for a variety of purposes. When used in a built-up area it is often placed on a masonry base to raise it above the surrounding buildings.
• Sails
Common sails consist of a lattice framework on which a sailcloth is spread. The miller can adjust the amount of cloth spread according to the amount of wind available and power needed. In medieval mills the sailcloth was wound in and out of a ladder type arrangement of sails. Post-medieval mill sails had a lattice framework over which the sailcloth was spread, while in colder climates the cloth was replaced by wooden slats, which were easier to handle in freezing conditions. The jib sail is commonly found in Mediterranean countries, and consists of a simple triangle of cloth wound round a spar. In all cases the mill needs to be stopped to adjust the sails. Inventions in Great Britain in the late 18th and 19th century led to sails that automatically adjust to the wind speed without the need for the miller to intervene, culminating in Patent sails invented by William Cubitt in 1813. In these sails the cloth is replaced by a mechanism of connected shutters. In France, Berton invented a system consisting of longitudinal wooden slats connected by a mechanism that lets the miller open them while the mill is turning. In the 20th century increased knowledge of aerodynamics from the development of the airplane led to further improvements in efficiency by German engineer Bilau and several Dutch millwrights. The majority of windmills have four sails. Multi-sailed mills, with five, six or eight sails, were built in Great Britain (especially in and around the counties of Lincolnshire and Yorkshire), Germany and less commonly elsewhere. Earlier multi-sailed mills are found in Spain, Portugal, Greece, parts of Romania, Bulgaria and Russia A mill with an even number of sails has the advantage of being able to run with a damaged sail and the one opposite removed without resulting in an unbalanced mill.