SAWING. 
and the teeth exquisitely sharpened, to 
make its way more gently, and yet with 
great expedition, in cutting offlegs, arms, &c. 
Saws are now generally used by butchers 
in separating the bones of the meat; the 
divisions by the saw are neater than those 
by the chopper, and there is a certain saving, 
as the chopper splinters bones, the parts of 
which cannot be incbided in the weight. 
SAWING, dividing timber, &c. by the 
application of a saw, either by the hand or 
mill. The mechanism of a sawing-mill may 
be reduced to three principal things, the 
first, that the saw be drawn up and down 
as long as is necessary, by a motion commu- 
nicated by water to the wheel : the second, 
that the piece of timber to be cut into 
boards be advanced by an uniform motion 
to receive the strokes of the saw ; for here 
the wood is to meet the saw, and not the 
saw to follow the wood, therefore the mo- 
tion of the wood and that of the saw ought 
immediately to depend the one on the 
other : the third, that when the saw has cut 
through the whole length of the piece, the 
machine stops of itself, and remains im- 
moveable; for fear, lest having no obstacle 
to surmount, the force of the water, or steam, 
should torn the wheel with too great rapi- 
dity, and break some part of the machine. 
In Plate Saw-mill are drawings of a cir- 
cular saw-mill, used by Mr. George Smart, 
at his manufactory for hollow-made masts, 
Westminster Bridge. Fig. 1 is an elevation 
of the machine ; tig. 2, a plan ; and tig. 3 
and 4, the saw' shown separately. 
The machine is turned by e. horse-wheel, 
which gives motion to a pinion on a hori- 
zontal shaft ; a spur wheel is fixed on this 
shaft, and turns a pinion on another hori- 
zontal shaft, on which the wheel A, (fig. 1) 
is fixed : this wheel is in the room over the 
machine, and the bearings for the gudgeons 
of the shaft are supported on the joists, B, 
of the floor: by means of an endless strap 
passing round this wheel, and also round a 
pulley, N, on the spindle of the circular 
saw, a rapid motion is given to the saw', 
which is made of well-tempered steel plate 
(fig. 3), with teeth on its edge : it is fixed 
on its spindle, D, (tig. 4) by a shoulder, d, 
against which it is held by another move- 
able shonlder, f, pressed against the other 
by a nut, k, on the end of the spindle which 
is tapped into a screw to receive it. The 
saw has a a circular hole through the mid- 
dle, fitting tight upon the spindle, and a 
small fillet fitting into the notch, a, (fig. 3) 
causes them to turn together. 
The ends of the spindle are pointed, and 
that point nearest the saw works in a hole 
made in the end of a ssrew screwed in a 
bench, E F G H, (fig. 1 and 2) made of 
stout planks, and well braced together; the 
other turns in a similar screw screwed 
through a cross beam, K, morticed between 
two vertical beams, L L, extending from 
the floor to the ceiling: the cross beam, K, 
can be raised or lowered in its mortices 
through the beams, L, by wedges put both 
above -and below its tenons. In order to 
adjust the plane of the saw perpendicular to 
the plane of the bench, M M, is a long pa- 
rallel ruler, which can be set at any distance 
fronf the saw, and fixed by screws going 
through circular grooves, g g, cut through 
the bench. In using tlie machine, the rii- 
ler, M M, is to be set the proper distance 
from the saw of the piece of wood to be 
cut, and as the saw turns round, a w'orkman 
slides the end of a piece of wood to il, 
keeping its edge against the guide, M M, 
that it may cut straight. 
When the saw requires sharpening, one 
of the screws at the end of its spindle must 
be turned back : the spindle and saw can 
be then removed; and by taking off the 
nut, k, the saw will be loose, and may be 
fixed in a common vice to whet it, in the 
same manner as a common saw : tlie teeth 
of the saw are set, that is, bent out of the 
plane of the saw', one tooth on one side, the 
next on the other : the outsides, r, (in fig. 3) 
of the teeth are not tiled to leave a surface 
perpendicular to the plane of the saw, but 
inclined to it, and in the same direction that 
each tooth so filed is bent in the setting : by 
this means the saw, when cutting, first takes 
away the wood at the two sides of the kerf, 
leaving an angular ridge in the middle of it, 
the use of which is to keep the saw steady 
in a right line, that it may not have so much 
tendency to get out of the straight in any 
place where the wood is harder at one side 
tlian on the other. 
In early periods, the trunks of trees W'ere 
split with wedges intoi as many and as fliiii 
pieces as possible, and if it were necessary 
to have them still thinner, they were hewn 
on both sides to the proper size. This 
simple and w'asteful manner of making 
boards has been still continued in some 
places to the present time. Peter the 
Great of Russia endeavoured to put a stop 
to it, by forbidding hew n deals to be trans- 
ported on the river Neva. The saw, how- 
ever, though so CDiivenient and beneficial, 
has not been able to banish eiilirely tlie 
