Stone dresser the Syleham windmill in Suffolk. This ancient trade involves sharpening the grooves and furrows in the millstones by gently chiselling them with a tool called a Millers Bill, as seen here.
Rotary quernstone Rotary querns were used in the Iron Age to grind corn, possibly as early as 400 BC. A central hole in the upper stone was filled with grain. The stone was rotated to produce coarse flour, which gradually spilled out between the two stones.