Fig. 402 represents a plain and an angular boring machine, adapted for heavy work, costing respectively 22s. and 30s. without augers; a set of augers to match, 1/2 in., 5/8 in., 3/4 in., 7/8in., 1 in., 1 1/4 in., 1 1/2 in., 1 3/4 in., and 2 in., costs 42s. 6d. The diagrams will explain themselves.