backsaws is the marking knife. This leaves a cleaner line than a pencil would and it cuts the fibres at the surface of the wood. Without this, the action of the saw would lift them and leave a ragged edge. References Young, F. Every Man his own Mechanic (1881) Oxford English Dictionary (1978) Hazra choudhary, A text book on workshop technology Footnotes Note 1: In North America, the name sash saw is used for a frame saw used in sawmilling. Saws Woodworking hand tools Woodworking