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cross 6 * J ' a - te ’ as t ^ le saw 111 a y employed in ripping or in

teeth ?"***' or cutt ' n g perpendicular to the fibres. Thenat 1 ° aP saws > except turning and key-hole saws, are alter-t , e , y ^ent on contrary sides of the plate, so that all thet j^ e 1 on the same side are alike bent throughout the length ofk. . e > for the purpose of clearing the sides of the cut made« m the wood.

th,

Of all

cutting tools whatever, the saw is the most useful to

e joiner, as the timber or wood which he employs can best fr lnto S '’P S or bars any size, with no more waste ofof l t laa a 8 ^ ce > the breadth of which is equal to the depththe piece to be cut through, and the thickness equal to theance of the teeth between their extreme points on theto k nate 8 hies of the saw, measured on a line perpendiculart 116111 : whereas, without the use of the saw, cylindricalth 68 C0U ^ on ly he reduced to the intended size by means ofj axe > in the use of which there would not only be anWense consumption of stuff, but also much greater labourold be required to reduce it to a straight surface.

Su 0, ners us e a small axe, called a hatchet, for cutting off theis l >er ^ uous wood from the edge of a board, when the wastenot of sufficient consequence to be sawed,hut l a ^ ove are what are commonly denominated edge tools,an l t lere are others required to regulate the forms. Allsaf 68 w h atever are formed by other reversed angles of the0ne e number of degrees ; as an exterior angle by an interioris ’ n 0 '! *h e contrary. The instrument for trying right anglesCall a** a s 9 uare i and those for trying oblique angles areare^i ^ eve ^ s - -The two sides which form the edge of a squareahl Wa y s stationary, but those of bevels are generally move-°ne leg upon the other, round a joint. In some cases,th e 6re a great number of pieces are required to be wrought tosame angle, a stationary bevel, called a. joint-hook, is used,bi'e ,)*? n 11 13 required to reduce a piece of stuff to a parallelgen i an instrument called a gauge is used, which consistsWlii oP a 8f l uare piece, with a mortise in it, throughf Ur . 1 lun s a sliding bar, at right angles, called the stem,i e ctinJ C< * ' Vlt ^ a s h ar P po in t> or tooth, at one extremity, pro-gaun^f a Ptt ^ e from the surface, so that when the side of thetl le ® ’ next to the end which has the point, is applied uponstern ertlca i surface of the wood, with the toothed side of theal ter u P° n the horizontal surface, and pushed and drawnWin hy the workman from and towards him, the tooth

p ar 11 | e an incision from the surface into the wood, at athe ricrt,^ 181111166 i >rom fi* e upper edge of the vertical side onth e si. 1 hand. This line marks precisely the intersection ofis to h " e w h* c h divides the superfluous stuff from that which

When

ga u „ e 1 a Mortise is required to be cut in a piece of wood, ainstrn WU ^ two teet h 18 used. The construction of thisstein h 6nt 18 same as fi ie common gauge, except that theits end 8 a b>ngitudinal slider with a tooth projecting fromfarther’f° ^ lal both teeth may be brought nearer, or removedfrom ,1 10111 each other, at pleasure ; and also to any distance,stem. * 6 Pace °h the head or guide, within the reach of theIf

be Si'uv V j 6 ” a P' ece of wood has been planed, it is required tooperatic acr ° ss the fibres ; to keep it stationary during thebt'uised n> t0 P revent the sides or edges from beingoppoaitg a, rl at P‘ ece op wood with two projecting knobs onI'lie ver( SIf i ’• one at eac h e, 'd, called a side-hook is used.Pbicej clcr S '^ e tPe lnter >or angle of one of the knobs istop 0 f ^e to the vertical side, and the under side upon theink Oench ; then the wood is nrp.ssed no-ainst the knob

1 Used.

Whi c k „ .

But thi pr °jects

then the wood is pressed against the knob.m le from the upper surface while it is cutting.

More stead 6 two sl ^ e ‘h°oks is better, as they keep the piece

v ot. a. y ‘

Q

When it is required to cut a piece of wood to a mitre withone side—that is, to half a right angle—joiners use a trunkof wood with three sides, like a box without ends or a top, |the sides and bottom being parallel pieces, and the sides ofequal heights ; through each of the opposite sides is cut akerf, in a plane perpendicular to the bottom, at oblique anglesof 45° and 135° with the planes of the sides; and anotherkerf is made with its plane at right angles to the two former :this trunk is called a mitre-box. When the wood is to be cut,the mitre-box is fixed steady against two side-hooks, and thepiece, which must always be less than the interior breadth ofthe mitre-box, is laid in it, and pressed against its fartherinterior angle, with the side downwards, to which the saw-kerf is intended to be perpendicular, and in this position it isto be cut. The two kerfs in the sides of the mitre-box arerequisite, in order to form the acute angle on the right or left-hand side of the piece, as may be required.

When a piece of wood is required to be made straight inone direction, joiners use a slip of wood straightened on oneedge, and thence called a straight edge. Its use is obvious ;as by its application it will be seen whether there is a coin-cidence between the straight edge and the surface,

When it is required to know whether the surface of a pieceof wood is in the same plane, joiners use two slips, eachstraightened on one edge, with the opposite edge parallel, andboth pieces of the same breadth between the parallel edges:each piece has therefore two straight edges, or two parallelplanes. Therefore, to find whether a board is twisted, or itssurface plane, the workman lays one of the slips across theone end, and the other across the other end of the hoard, withone of the straight edges of each upon the surface ; then helooks in the longitudinal direction of the board, over theupper edges of the two slips, until his eye and the said twoedges are in one plane ; or otherwise, the intersection of theplane passing through the eye and the upper edge of thenearest slip, will intersect the upper edge of the farther slip.

If it happen as in the former case, the ends of the wood underthe slips are in the same plane ; but should it happen as inthe latter, they are not. In this last case, the surface is saidto wind; and when the surface is so reduced as for every twolines to be in one plane, it is said to be out of winding, whichimplies its being an entire plane ; from the use of these slips ithey are denominated winding-sticks.

Before we proceed to the method of bringing a roughsurface to a plane, it is necessary to show how to make astraight edge. And here the joiner must not lose sight of theproperties of a straight-line, viz., that which will alwayscoincide with another straight line, however they may beapplied together.

The operation of making the edge of a board straight iscalled by joiners, shooting, and the edge so made is said to beshot. |

Straight edges may be formed by planing the edges of two jboards, and applying them together, with their superficies or Ifaces in the same plane ; if there be no cavity in the joint, the (edges will be straight; if not, the faces must be applied toeach other, the edges brought together, and planed and triedas before, until they coincide.

Another mode is by having a plane surface given :—Planethe edges of a board as straight as the eye will admit of, applythe face of it to that of the plane, and draw a line by the edgeof the board ; turn the board over with the other side uponthe plane, bring the planed edge to the line drawn before, andthe extremities of the edge to their former places, and drawanother line ; then, if all the parts of this line coincide withthe former, the edge is already straight, but if not, repeat theoperation as often as may be necessary. j