and
pointing forward. These guards are about three inches apart, of a
suitable size, say three-quarters of an inch square, more or less, at
the base, and lessening towards the points. The guards are formed of a
top and bottom piece, joined at the point and near the back, being
nearly parallel, and about one-eighth of an inch apart, forming a
horizontal mortice or slit through the guard; these mortices being on a
line with each other, form a continued range of openings or slits
through the guards. The first guard is placed on the rear of the right
wheel, and the last at the extreme end of the platform, and the
intermediate guards at equal distances from each other, and three inches
apart, more or less, from center to center.

[Illustration: Diagram Showing Arrangement of Guards and Knives]

[Sidenote: The Cutter]

"The cutter or saw (f) is formed of thin triangular plates of steel
fastened to a straight _flat rod_, (g) of steel, iron or wood, one inch
and a half wide; these steel plates are arranged side by side, forming a
kind of saw with teeth three inches at the base, and four and a half
inches long, more or less, sharp on both sides, and terminating nearly in
a point. The saw is then passed through all the guards in the aforesaid
range of mortices, the size of the mortice being suited to receive the
saw with the teeth pointing forward; observing always that the points of
the saw teeth should correspond with the center of the guards. One end of
the saw is connected with a pitman moved by a crank, and receiving its
motion from the main axis, by one or two sets of cog wheels. The
vibration of this crank must be equal to the distances of the centers of
the guards, or the points of the saw teeth, or thereabouts, so when the
machine is in motion, the point of each saw tooth may pass from center to
center of the guards on each side of the same tooth at every vibration of
the crank; if the main wheels are three feet four inches in diameter,
they should in one revolution give the crank sixteen vibrations, more or
less; the saw teeth should play clear of the guards, both above and
below. * * *

[Sidenote: Operation]

"The power is given by locking the wheels to the main axis, the machine
has one square wheel box, the other round and locked at pleasure. If the
power should be wanted, one, two, or more horses are attached and driven
on the stubble before the machine, the right wheel running near the
standing grain, the pla