669. Kinds of labour prohibited in cells, grinding mills.
(1)The forms of labour selected for cells should as far as possible, be such as will not facilitate escapes or suicides. If it is necessary to employ prisoners on other tasks, special precautions should be taken.(2)Grinding mills in cells should be raised about 4 feet off the ground on masonry pillars into which the lower stone should be firmly fixed. The upper stone should not be allowed to remain in the cell after the day's work is over.
