A Smock mill is like a Tower mill in that the main structure does not
rotate. The sails are mounted on a rotating cap. The main structure of a smock
mill is built of timber and is usually octagonal, on a masonry base.
The cap is rotated either by hand, usually using gearing worked by chain from
below or by a drive from a fantail.
There are very few smock mills remaining in Essex and this one in Upminster
(shown on the left) is the best example. The remaining examples at Great
Bardfield, Terling and Orsett have all lost their sails and been converted
into dwellings.