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Definitions.

5. The wood employed in Joinery is in the state of BOARDS, PLANKS, and BATTENS; thus distinguished according to their breadths: BATTENS are from two to seven inches wide; BOARDS, from seven to nine inches; and PLANKS, from nine inches to any indefinite breadth.

The OPERATIONS of JOINERY consist in making surfaces of various forms; also of GROOVING, REBATING, MOULDING, MORTISING, and TENONING.

6. SURFACES, in Joinery, may be either plane or curved; but they are most frequently plane. Every kind of surface is first formed in the rough, and then finished by means of various appropriate tools.

7. GROOVING and REBATING consist in taking or abstracting a part which is every where of a rectangular section. A REBATE is formed close to the edge of a piece; and a GROOVE, at some distance from the edge.

8. A MORTISE is a cavity formed within the surface, for the purpose of receiving the end of a piece of timber, to be joined at a given angle. The end, which must be very nicely fitted into the mortise, in order to make the two pieces as strong as possible, is called a TENON. As the sides of the mortise are generally perpendicular to the sides of the piece, and at some distance from the sides of the piece in which the mortise is, a tenon is generally stopped by projecting sides, which are closely fitted upon the side of the piece of wood in which the mortise is made; and the parallel faces of both are made flush, and so closely united, as to appear almost like one single piece. That part of the surface of the piece which has the tenon, which comes in contact with the surface of the piece in which the mortise is made, is called the shoulder of the tenon.

9. FRAMES are joined together, so as most frequently to form a rectangle, with one, two, or more, rectangular openings: these openings are closed with thin boards, fitted into grooves in the interior edges of the frame, called PANNELS. In ornamental work, the edges of the frame next to the pannels, are moulded. The two outer vertical pieces of the frame, are denominated the STILES; all the cross-pieces are denominated RAILS; and the vertical pieces, that separate the pannels, MOUNTINGS; or, in Gothic work, MULLIONS.

10. PLANKS and BOARDS are joined together by planing the edges straight and square, and rubbing them together with hot glue until the glue has been almost forced out of the joint; then the ends and the proper faces being brought to their places, the rubbing is stopped, and, when the glue is quite dry, the two boards thus fixed will be almost as strong as one en

tire board.

11. MOULDINGS have several names, according to their forms, connection, situation, or size. When the edge of a thin slip of wood is semi-circular, it is said to be rounded. Figure 2, plate XLIII, represents the section of a piece rounded on the edge.

When a semi-cylinder is formed on the edge of a piece of wood, within both surfaces, so that the diameter may be parallel to one side, this semi-cylinder is called a BEAD; and the recess, between the surface of the cylinder and the solid wood upon the side, which is parallel to its diameter, is denominated a QUIRK; and the whole part thus formed is called a BEAD and QUIRK.

Figure 3, plate XLIII, is the section of a piece of wood, where a bead and quirk is run on the edge.

12. A BEAD and DOUBLE QUIRK is when a three-quarter cylinder is formed on the edge, so that the surface of the cylinder may touch each adjoining face.

Figure 4 exhibits the section of a bead and double quirk.

13. A TORUS-MOULDING consists of a semi-cylinder, and two rectangular surfaces, one perpendicular to the diameter, and the other in the diameter produced.

Figure 5 is a torus-moulding: the small rectangular surface in the plane of the diameter is denominated a FILLET.

Figure 6 exhibits the section of a DOUBLE TORus.

14. A FLUTE is the concave surface of the section of a cylinder or cylindroid, depressed within the surface of a piece of wood.

Figure 7 exhibits the section of a piece of wood with three flutes on it.

15. When a piece of wood is formed into two or more semi-cylinders, touching each other, the semi-cylinders are called REEDS, and the piece of wood is said to be reeded.

Figure 8 exhibits the section of a piece of wood with four reeds wrought upon it.

16. Figure 9 is the section of a moulding denominated an OvOLO or QUARTER ROUND. It consists of the fourth part of the convex surface of a cylinder.

17. Figure 10 is the section of a moulding called a CAVETTO, or hollow, consisting of the fourth part of the concave surface of a cylinder.

18. Figure 11 is the section of a CYMA-RECTA, consisting of a round and hollow joined together by one common tangent plane; the one part of the surface being concave, and the other convex.

This curve may be drawn when the parts are composed of parts of circles, by joining the extremities a and c of the moulding: bisect ac in the point b, and draw de parallel to the longitudinal direction of the moulding; make ad and ce perpendicular to de; from d, with the radius da, describe the arc ab; from e, with the radius ce, describe the arc bc; and a bc is the moulding required.

But architects, most esteemed for their good taste, never draw the forms of mouldings by these mechanical methods; they always make them of the most beautiful figures they can by the hand; and, like the ancient Greek architects, they avoid circles for mouldings, in consequence of their want of variety, both of outline and of light and shade. Hence, though we give the usual mechanical methods, they are not here recommended to be used in practice.

Figure 12 is also the section of a cyma-recta, of which the concave and convex parts are equal portions of a circle, but each portion less than the quarter.

To draw this curve, join the extremities a and b, and bisect ab in c: from a, with the radius a c, describe an arc ce; and from b, with the radius bc; describe an arc, cd; from c, with the radius ca, describe an arc, ae, as also the arc bd. With the same radius, from the centre e, describe the arc ac; and with the same radius, from the centre d, describe the arc cb; then acb is the curve, which is the section of the surface of the moulding.

19. Figure 13 is the section of an OGEE moulding, sometimes called a CYMA-REVERSA: this moulding is of the same form as the cyma-recta, except that the concave portion of the moulding of the one is where it is convex in the other.

20. Figure 14 is the section of a moulding called a SCAPE, which is composed of the quarter of the circumference of a cylinder, and a plane surface, which is a tangent to the cylindric sur face, in the line of their meeting.

21. Figure 15, part of the section of an ovolo with three fillets, which, when circular, or encompassing a column, are called ANNULETS.

Figure 16 is the section of a moulding denominated a QUIRKED OVOLO. This may be drawn thus: Suppose it were required to touch the line de at the point d: draw dg perpendicular to

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PL. XLI

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