A smock mill differs from a conventional tower mill which is usually built with brick or stone. A smock mill is constructed around a wooden frame with a clapboard or thatch exterior. As in a tower mill, the cap can be rotated to ensure that the sails face in an optimal direction to catch the best of the wind. Smock mills first appeared in Holland in the early 16th century, and were quickly recognised as an efficient way of providing power to pump water and thus drain marshy areas — and then to keep those areas dry thereafter. As described in our feature above, Eric’s smock mill is on the Wimmenumer Polder near the village of Egmond aan den Hoef. The area was first drained in 1556.

While smock mills were most commonly used in Holland in water management, elsewhere they found other uses.