Post mill

From Wikipedia, the free encyclopedia

The post mill is the earliest type of European windmill. The defining feature is that the whole body of the mill that houses the machinery is mounted on a single vertical post, around which it can be turned to bring the sails into the wind. The earliest post mills in England are thought to have been built in the 11th and 12th centuries. The earliest working post mill in England still used today is to be found at Outwood in Surrey^[1]. It was built in 1665. The earliest remaining example of a non operational mill can be found in Great Gransden in Cambridgeshire, built in 1612.^[2] Their design and usage peaked in the 1700s and 1800s and then declined after the introduction of high-speed steam-driven milling machinery^[3] Many still exist today, primarily to be found in Northern Europe and Great Britain. The term peg mill or peg and post mill (in which the "post" was the tailpole used to turn the mill into the wind) was used in north west England, and stob mill in north east England, to describe mills of this type.

Contents 1 Types of post mill 1.1 Sunk post mill 1.2 Open Trestle post mill 1.3 Post mill with roundhouse 1.3.1 Midlands post mill 1.4 Hollow Post mill 1.5 Composite mill 1.6 Paltrok mill 2 References 3 Sources. 4 External links

[edit] Types of post mill

There are many variations amongst post mills.

[edit] Sunk post mill

The earliest post mills were quite small, and this led to problems with stability as they were liable to blow down in strong winds. A solution was found by burying the bottom of the trestle in a mound of earth.^[4]. The last sunk post mills in England were at Warton, Lancashire,^[5] and Essington, Staffordshire.

[edit] Open Trestle post mill

As mills were made bigger, it was found that the trestle did not need to be buried. Thus the open trestle post mills were built. The oldest surviving is at Great Gransden, Cambridgeshire. Others exist in the UK at Bourn, Cambridgeshire; Great Chishill, Cambridgeshire; Nutley, Sussex and Chillenden, Kent. Open trestle post mills are also found in France, Belgium, the Netherlands, Germany and in New England, USA.

[edit] Post mill with roundhouse

The space around the trestle could be used for storage, but was open to the weather. Mill owners started to build roundhouses around the trestles, and later mills were built with a roundhouse from new. This had the dual advantage of creating a covered storage area and protecting the trestle from the weather. In Suffolk, millwrights would build post mills mounted on tall, two or three storey roundhouses, as at Saxtead Green.

[edit] Midlands post mill

In the Midlands and North West of England, the top of the roundhouse had a curb, and rollers affixed to the mill body enabled the roundhouse to bear some of the weight of the mill. Examples of Midlands post mills extant include Danzey Green mill, (preserved at the Avoncroft Museum of Historic Buildings) and the mill at Wrawby, Lincolnshire.

[edit] Hollow Post mill

Some post mills are hollow post mills. In these mills the main post is bored to take a driveshaft, similar to an Upright Shaft in a smock or tower mill. This enables the mill to drive machinery in the base or roundhouse. Hollow post mills were not common in the United Kingdom. In the Netherlands, they are called Wipmolen and were used for drainage. In France, the Moulin Cavier was a type of hollow post mill used for corn milling.

Hollow post mill

Wipmolen

Moulin Cavier

[edit] Composite mill

A few mills looked like post mills, but were not post mills. These composite mills often had a post mill body mounted on a short tower resembling a roundhouse, as at Banham^[6] and Thornham^[7] in Norfolk. Composite mills lack the central post on which the body of the post mill is mounted and turns upon to enable the mill to face the wind.

[edit] Paltrok mill

In the Netherlands, a variety of mill called the Paltrok mill was built for sawing wood. These mills resemble square smock mills, and are technically composite mills although the tower is very short and of large diameter. There are five paltrok mills remaining in the Netherlands, at Zaansche Schans, Haarlem, Zaandam, Amsterdam and at the National Heritage Museum, Arnhem. Other Paltrok mills survive in Germany.^[8]

[edit] References

[edit] Sources.

• Smith, Arthur C (1977). Windmills in Huntingdon and Peterborough, a contemporary survey. Stevenage: Stevenage Museum. ISBN 0 9504239 47. 
• Jarvis, P S (1982). Stability in Windmills. Reading: TIMS. 

[edit] External links

• Outwood Windmill Website
• Sussex Mills Group information on Post mills