 John Milne patented a machine in 1765 which used several grades of wire mesh or cloth to separate flour from bran.A machine for manufacturing bolting cloth, used to filter the flour from bran and other parts of the grain, was patented in 1783 by Benjamin Blackmore.And in 1850, James Bell devised a means of separating flour by pushing the feedstock (or 'stock') against a vertical cloth ('bolting sleeve') while Joseph Foot patented a means of making the filter sleeve from silk instead of wool.