Trestle and Roundhouse
The trestle is of oak. The crosstrees are 22 feet (6.7 m) long, of normal section. The main post is 18 feet (5.5 m) in length, and 28 inches (710 mm) square at its base and 20 inches (510 mm) diameter at the top. The underside of the lower crosstree is 6 feet 6 inches (1.98 m) above ground level. The roundhouse is of brick, with a boarded roof covered in tarred felt. A pair of underdrift millstones is located on the upper floor of the roundhouse, these were driven via a portable steam engine in times of calm. The roundhouse was originally built as a single-storey structure, it and the mill being raised a storey at a later date.
Read more about this topic: Bocking Windmill, Description