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Surfaces, in joinery, are either plane or curved, but mostfrequently plane. All kinds of surfaces are first formed inthe rough, and finally brought to a finish by means of appro-priate tools.

Grooving consists in taking away a part of a rectangularsection from a piece of wood, so as to form a channel ofequal breadth throughout, with three surfaces, one parallel,and the other two perpendicular, to that of the wood ; whichchannel is called a groove; and thus the piece that wouldfill the cavity, or which would restore it to its original form,is a square prism.

Rebating consists in taking away a part from a piece ofwood of a rectangular section, so as to leave only two sides,one perpendicular, and the other parallel, to the surface ofthe wood; the cavity thus formed is called a rebate. Fromthis definition it is manifest, that a rebate can only be formedby reducing the piece of wood to be rebated at the angleitself, and may therefore be considered as a semi-groove;and thus the piece which would restore the whole to itsoriginal form is a square prism, as in grooving.

A mortise is a cavity recessed within the surface of a pieceof wood, with four sides perpendicular to the surface, and toeach other. The act of making a mortise is called mortising.

A tenon is a projection formed on the end of a piece ofwood with four plane sides, at right angles to each other,and to a plane, from which it projects, called the shoulder ofthe tenon.

In the following, all pieces of wood whatever are supposedto be rectangular prisms, and the length in the direction ofthe fibres ; two of the sides of every mortise perpendicular,and the other two parallel, to the fibres; and the four sidesof every tenon in the direction of the fibres, unless otherwisedescribed : likewise, if two of the surfaces of a piece of woodbe of greater breadth than the other two, the latter are calledthe edges, and the former the sides; while each line of con-course, formed by two adjacent sides, is called an arris.

Moulding consists in forming the surface of a piece byplane or curve surfaces, or by both, in such a manner, thatall parallel sections may be similar and equal figures.

The first thing to be done in joinery is to select the stuffor boards, which ought to be well seasoned for every purposein joinery, and then line it out; and if the stuff be notalready at the size, as is most frequently the case, it must beripped out with the ripping-saw, or cross cut with the hand-saw, or both, as may be wanted. The next thing is theplaning of the stuff, first upon a side, then the edge squared,and afterwards gaged to a breadth and thickness, shouldeither or both be found necessary.

Two or more pieces of stuff may be fastened together, invarious ways, by pins of wood, or by nails ; but in work pre-pared by the joiner for building, the pieces are more fre-quently joined together by making their surfaces planes, andplastering them over with a hot tenacious liquid, called glue,then rubbing the surfaces until the glue has been almostrubbed out, and one piece brought to its situation with respectto the other. The best work is always joined by this method.

When boards are required of a greater breadth thancommon, several primitive boards must be fastened togetheredge to edge, either by nailing them to pieces extendingacross the breadth, or by gluing them edge to edge, or byjoining pieces transversely together with small boards, tonguedinto grooves excavated in the edges.

Two pieces of stuff are joined together at right or obliqueangles by a mortise and tenon adapted to each other, andfastened together with glue.

When a frame, consisting of several pieces, is required, themortises and tenons are fitted together, and the joints glued all

at one-time, then entered to their places, and forced togetherby means of an instrument called a cramp.

A frame of wood in order to contain a panel, and surroundit completely, cannot be made of less than three pieces,unless one or more of them be curved, because less thanthree straight lines cannot contain a space.

The operation of forming a given surface, by taking awaythe superfluous wood, is called planing, and the tools them-selves planes.

The first tools used by joiners are bench planes, whichgenerally consist of a jack plane, for taking away the roughof the saw and the superfluous wood, only leaving so much asis sufficient to smooth the surface ; the trying plane, tosmooth or reduce the ridges left by the jack-plane, and tostraighten or regulate the surface, whether it be plane orconvex ; the long plane, when the surface is required to bevery straight ; and the smoothing plane, in smoothing, as itsname implies, and giving the last finish to the work.

Besides the bench planes, there are others for forming anykind of prismatic surfaces whatever, as rebating planes, groov-ing planes, and moulding planes: but for a more particulardescription of these and the bench planes, we shall refer tothe article Plane.

The tools employed in boring cylindric holes are a stockwith bits, of various descriptions and sizes, gimlets, andbradawls of several diameters.

The tools used in paring the wood obliquely, or across thefibres, and for cutting rectangular prismatic cavities, are ingeneral denominated chisels : those for paring the wood acrossthe fibres are called Jirmers, or paring chisels, and those forcutting mortises are called mortise chisels. The sides of allchisels, in a direction of their length, are straight, and theside of a chisel which contains the cutting edge at the end isof steel. The best paring chisels are made entirely of caststeel. Chisels for paring concave surfaces are denominatedgouges.

Dividing wood, by cutting away a very thin portion of thematerial of equal thickness throughout, to any requiredextent, by means of a thin plate of steel with a toothed edge,is called sawing, and the instruments themselves are calledsaws, which are of several kinds ; as the ripping saw, fo rdividing boards into separate pieces in the direction of thefibres ; the hand saw, for cross cutting, or for sawing thinpieces in the direction of the grain ; the panel saw, either forcross cutting, or cutting very thin boards longitudinally ; thetenon saw, with a thick iron back, for making an incision ofany depth below the surface of the wood, and for cuttingpieces entirely through, not exceeding the breadth of thatpart of the plate without the iron back ; likewise a sash satv,and a dovetail saw, used much in the same way as the tenonsaw. From the thinness of the plates of these three lastsaws, it is necessary to stiffen them by a strong piece of metal,called the back, which is grooved to receive the upper edg eof the plate that is fixed to the back, and which is therebysecured and prevented from crippling. When it is require 1to divide boards into curved pieces, a very narrow saw with-out a back, called a compass saw, is used ; and in cutting avery small hole, a saw of a similar description, called a keyhole saw, is employed. All these saws have their plate 9longer and thinner, and their teeth finer, as they succeed end 1other in the order here mentioned, excepting the two l> ist ’which have thicker plates and coarser teeth than either th®sash or dovetail saws. The external and internal angles othe teeth of all saws are generally formed at an angle ofdegrees, and the front edge teeth slope backward in a sro*degree, but incline or recline from the straight line dra'trfrom the interior angle perpendicular to the edge in the pl aD