A pair of small cast-iron chain pulleys set side-by-side, on a common spindle, to which both are evenly eccentric. Part of spring sail linkage to increase, progressively, the purchase of the shutters as they open against the spring (Kent & Sussex).
Drawing of air through the stones, thus reducing the temperature of the stones and the meal produced. Dust is drawn away from the working millstones at the same time thus preventing a build-up of combustible material.
(1) The hole in the centre of the runner millstone through which the grain passes to be ground. See SWALLOW. Can also be applied to the hole in the centre of the bedstone.
(2) The inner third of the grinding surface of a MILLSTONE.
A term relating to windmill sails, in which, when the sails are directly facing the direction from which the wind is blowing, they are said to be facing the Eye of the Wind. This is a condition for obtaining maximum power.