Fig. 131. The spirit level

RULE

A two-foot, four-fold, boxwood rule, graduated to eighths outside and sixteenths inside, will answer all ordinary requirements. ([Fig. 132].)

THE STEEL SQUARE

Fig. 132. Steel square and rule

This simple but valuable tool, about which volumes have been written, is necessary for building construction, but is not needed in the making of furniture or cabinet work.