can be done by pulling on a rope or chain, or if the mill is working, by hanging sufficient weight on the rope or chain to allow the shutters to be kept closed in a gentle wind. A strengthening wind begins to blow the shutters open, as its force more than counteracts the weight. As the shutters open, the force on the sweeps is reduced. How the energy is put to workThe sweeps cause the windshaft to rotate. Around the shaft is bolted an iron brakewheel 2.62 metres in diameter. This is fitted with a large wooden brake which can hold the sweeps stationary. The brakewheel is also a gear wheel, fitted with wooden teeth.A small section of the brakewheel can be seen at the back of the photograph on the left. The brown area beneath the teeth is part of the brake. The teeth on the brakewheel engage with teeth on a smaller wheel, the "wallower" (seen on the left), which is connected by a vertical shaft to the great spur wheel two floors below it. It also drives the sack hoist, seen to the right of the picture. The sack hoist lifts sacks of grain up through trap doors from ground level. The grain is then tipped through apertures in the floor. The storey beneath is the totally enclosed bin floor, which holds the grain ready for processing. From here it is directed down chutes to apertures at the centre of the rotating upper millstones on the floor below. These are suspended a small but adjustable distance above the stationary lower stones, in the surface of which fine channels were incised to provide a cutting action.Pictured in the centre of the photograph on the left is the great spur wheel, which drives three "stone nuts", the smaller gear wheels which turn the upper millstones. Two of the smaller gear wheels can be seen top left and bottom right.On the left and right are two of the large wooden beams which help the brick tower support the weight of the heavy machinery. The beams beneath the next floor down take the weight of six millstones. ...
