Anyone who has used a file knows what skill is required to produce flat surfaces. A fixture which is nothing more than a mirror properly placed enables the operator to sight along the file and see at all times just how the file is running. - Contributed by A. F. Stearns, Madison, Wis.

The File can be Seen in the Mirror and Its Direction Controlled for Filing Flat Surfaces

Ill: The File can be Seen in the Mirror and Its Direction Controlled for Filing Flat Surfaces