the bevel, as shown at C, so the clamps will fit on the saw
around the saw handle.

[Illustration: _Fig. 15._]

When the saw is placed between these clamps and held together by the
jaws of the vise, you are ready for the filing operation. Observe the
following _filing suggestions_: Always hold the file horizontal or
level. In filing, use the whole length of the file. Do the work by a
slow, firm sweep.

Do not file all of the teeth along the saw at one operation, but only
the alternate teeth, so as to keep the file at the same angle, and thus
insure accuracy; then turn the saw and keep the file constantly at one
angle for the alternate set of teeth.

Give the same number of strokes, and exert the same pressure on the file
for each tooth, to insure uniformity. Learn also to make a free, easy
and straight movement back and forth with the file.

THE FILE.--In order to experiment with the filing motion, take two
blocks of wood, and try surfacing them off with a file. When you place
the two filed surfaces together after the first trial both will be
convex, because the hands, in filing, unless you exert the utmost
vigilance, will assume a crank-like movement. The filing test is so to
file the two blocks that they will fit tightly together without rolling
on each other. Before shaping and planing machines were invented,
machinists were compelled to plane down and accurately finish off
surfaces with a file.

In using the files on saws, however small the file may be, one hand
should hold the handle and the other hand the tip of the file.

A file brush should always be kept on hand, as it pays to preserve files
by cleaning them.

[Illustration: _Fig. 16._]

THE GRINDSTONE.--As most of the tools require a grindstone for
sharpening purposes, an illustration is given as a guide, with a diagram
to show the proper grinding angle. In Fig. 16 the upright (A) of the
frame serves as a line for the eye, so that if the point of the tool is
brought to the sight line, and the tool (C) held level, you will always
be able to maintain the correct angle. There is no objection to
providing a rest, for instance, like the cross bars (D, D), but the
artisan disdains such contrivances, and he usually avoids them for two
reasons: First, because habit enables him to hold the tool horizontally;
and, second, by holding the tool firmly in the hand he has better
control of it. There is only one thing which can be said in favor of a
rest, and tha