The Rotary Dryer At one time the most widespread mechanical drying process in Cornwall's clay industry was the rotary dryer. The first installation at Rock Hill Kiln on the Goonbarrow branch fed rail traffic from a small store on the East Caudledown Mill siding from 1949. By the mid to late 1950's the now very familiar gigantic clay stores were being constructed to be fed by rotary dryers. By the time of the large scale industry layoffs around 2008/9, most of them had been shut down, having ope