The Pevensey windpump came from an old clay pit near Pevensey and Westham Station. This is a rare survival of a wooden windpump, a type which must have been quite common before the introduction of the more familiar American steel windpump, which in its turn has now almost vanished from the countryside. An engraving entitled ‘Sussex Brickfield Pump’, published in 1881, shows a windpump identical with the Pevensey example, and it is clear that there must have been many in the local landscape. Now perhaps three remain in south-east England.
The upper part of the structure carrying the sails is supported on a centre-post held upright by sloping ‘quarter bars’. The body of the mill turns on this centre-post to face the sails into the wind. This is done automatically by a large rudder projecting at the tail. The sails, fixed to an iron cross on the front of the windshaft, are of the type known as ‘common sails’, in which canvas is stretched over a wooden frame. On some windpumps — at Glynde, for example — boards were used instead of sails.
Power is transmitted from the sails and the windshaft to a vertical iron rod by cast-iron bevel gears. The iron rod passes down the hollow centre-post and, with another pair of bevel gears, drives a horizontal shaft below the post. On this shaft are fixed two eccentrics, which drive pump rods to cast-iron simple lift pumps, made by Thompson of Lewes. These are situated below the mill structure.