ade 2" thick, 6" wide, and long enough when in
position to reach from the floor to a point above the level of the
top of the stone. It is beveled at the lower end so as to rest snugly
against a cleat nailed down at the proper place on the floor. The
board is held in place by a loop of iron, B, which hooks into the
holes in the trough of the grindstone. In the board a series of holes
(say 1" in diameter) are bored. These run parallel to the floor when
the board is in place, and receive the end of the tool-holder. The
tool-holder consists of four parts: (1) a strip C, 1-1/2" thick,
and as wide as the widest plane-bit to be ground. The forward end is
beveled on one side; the back end is rounded to fit the holes in the
main board A. Its length is determined by the distance from the edge
of the tool being ground to the most convenient hole in A, into which
the rear end is to be inserted. It is better to use as high a hole as
convenient, so that as the grindstone wears down, the stick will still
be serviceable; (2) a strip, D, of the same width as A and 7/8" thick,
and 15" to 18" long; (3) a cleat, E, 5/8"x3/4", nailed across D; (4) a
rectangular loop of wrought iron or brass, F, which passes around the
farther end of the two strips, C and D, and is fastened loosely to D
by staples or screws.

[Illustration: Fig. 222. Grinding Device.]

[Illustration: Fig. 223. Holder for Grinding Chisels or Plane-Bits.]

The tool to be ground slips between this loop and the strip C, and
is held firmly in place by the pressure applied to the back end of D,
which thus acts as a lever on the fulcrum E.

Any desired bevel may be obtained on the tool to be sharpened, by
choosing the proper hole in A for the back end of C or by adjusting
the tool forward or backward in the clamp. As much pressure may be put
on the tool as the driving belt will stand without slipping off.

A still simpler holder for the plane-bit only, is a strip of wood
1-1/2" thick and 2" wide, cut in the shape G shown in Fig. 223. The
plane-bit fits into the saw-kerf K, and in grinding is easily held
firmly in place by the hand. By inserting the rear end of the stick G
into a higher or lower hole in the board A, any desired angle may be
obtained. G is shown in position in Fig. 221.

[Illustration: Fig. 224. Agacite Grinder.]

All such devices necessitate a perfectly true stone. The essential
features are, to have a rigid support against which the tool may be
pushed by th