De Bird is a Hollow Post mill in Grou, Friesland

Friesland

Friesland is a province in the north of the Netherlands and part of the ancient region of Frisia.Until the end of 1996, the province bore Friesland as its official name. In 1997 this Dutch name lost its official status to the Frisian Fryslân...

, Netherlands

Netherlands

The Netherlands is a constituent country of the Kingdom of the Netherlands, located mainly in North-West Europe and with several islands in the Caribbean. Mainland Netherlands borders the North Sea to the north and west, Belgium to the south, and Germany to the east, and shares maritime borders...

 which was built in the C18th. The mill is also known as De Burd and Koopmans Molen. Although not in full working order, it can turn in the wind. It is listed as a Rijksmonument

Rijksmonument

A rijksmonument is a National Heritage Site of the Netherlands, listed by the agency Rijksdienst voor het Cultureel Erfgoed acting for the Dutch Ministry of Education, Culture and Science.-History and criteria:...

, number 22915.

History

Although a mill has stood on this site since 1640, De Bird was built in the C18th. It was built to drain the De Burd polder, which was part of the Groot Jetsma farm. De Bird was built for A J de Jong. A later owner was Simon Koopmans, giving the mill its alternate name of Koopmans Molen. In 1878, the mill was sold at auction

Auction

An auction is a process of buying and selling goods or services by offering them up for bid, taking bids, and then selling the item to the highest bidder...

 for ƒ500.

Restorations of the mill were undertaken in 1950, 1960 and 1964. In November 1972, the mill was damaged in a storm. It was during the subsequent repair work that the roundhouse roof was tiled with pantiles. A further restoration was undertaken in 2004, during which the roundhouse roof was boarded, as it had been previously. The mill is not complete, as the Archimedes screw is missing, although it can turn by wind. The mill was officially reopened on 18 November 2005. Previously in the ownership of the Gemeente Boarnsterhim

Boarnsterhim

Boarnsterhim is a municipality in the northern Netherlands. The Dutch name is Boornsterhem.- Population centres :Akkrum, Aldeboarn , Dearsum , Eagum , Friens, Grou , Idaerd , Jirnsum , Nes, Poppenwier , Raerd , Reduzum , Sibrandabuorren ,...

, De Bird is now owned by Stichting Poldermolens De Lege Midden (Lege Midden Polder Mills Society).

Description

De Bird is what the Dutch describe as an spinnenkop. It is a hollow post mill on a single storey square roundhouse. The mill is winded by tailpole and winch. The roundhouse and mill body are covered in vertical boards, while the roof of the mill is boarded horizontally. The sails are Common sails. They have a span of 12.2 metre. The sails are carried on a wooden windshaft. The windshaft also carries the brake wheel which has 43 cogs. This drives the wallower (21 cogs) at the top of the upright shaft. At the bottom of the upright shaft, the crown wheel, which has 34 cogs formerly drove an Archimedes screw, which is now missing. The axle of the Archimedes screw was 925 millimetre diameter and the screw was inclined at 21½°.