Smock windmill, c 1840.
© Science Museum / Science & Society Picture Library
Sectioned model (Scale 1:24) of Smock windmill as it was in 1840. This windmill was originally built in 1814 by J D Humphrey of Cranbrook, Kent and was designed to grind corn. It owes its name to the appearance of its tapered wooden tower. In common with most European mills, it has vertical sails (designed by William Cubitt in 1807) which are rotated by the horizontal motion of the wind. Its remaining features show the lengths Humphrey went to to maximise the wind's energy. Its fantail and top cap ensure that the sails are always facing the wind. Furthermore, an instrument at the front allows each sail to turn away from the wind if it is too strong. Humphrey also installed a large gear to convert the speed of the sails.