viously nailed so that the nails be not seen in the faces, tais will answer every purpose of common dovetailing. As various methods are employed in connecting pieces of wood so as to form an angle, we shall here present the reader with so.ne of the best examples. Figs. 595 and 596 are methods of connecting two pieces of wood so as to form two internal right angles. Figs. 597, 598, 599, 600, 601, and 602, exhibit the joining of boards at an external angle. In Figs. 598 and 599 the external angle, being that which is exposed to sight, is rounded or beaded. Fig. 600 is the most common of mitres. Fig. 601, a lapped mitre, which is much stronger than Fig. 600. Fig. 603, dovetailing. Fig. 60, secret dovetailing. If several boards are required to be joined together to form a broad face, they are sometimes strengthened by fixing, with a tongue and groove, or mortise and tenon, another narrow piece across each end: the cross piece is termed a clamp, and the board thus constructed is said to be clamped. The most simple description of door is constructed of several boards simply rebated together, or each edge ploughed and tongued; these are confined together by a transverse piece, called a ledge nailed a cross, from which the door derives the name of a ledge-door. When strength, durability, and beauty are to be combined, a frame, joined by mortise and tenon, is constructed with one or more openings; and these penings are filled with pieces called panels, fitted into grooves, ploughed in the edges of the frame. The horizontal pieces of the framing are called, according to their situation, top-rail, bottom-rail, lock-rail, and frieze-rail. On the lock-rail the lock is either mortised in, or screwed on; and the frieze-rail is an intermediate rail between the top and middle rail. The extreme vertical pieces to which the rails are fixed are called stiles; and if there be any intermediate piece it is called a mounting. Doors derive their names according to the manner in which they are framed and the number of panels they contain, as one, two, four, six, &c. panelled doors; and are further described by the moulding and description of panel. Jib-doors are those which, when shut, are as much concealed as possible. They are used to preserve the uniformity of a room, or to save the expense of a corresponding door. Doors ought to be made of the best materials, perfectly seasoned, and firmly put together; the mitres or scribings should be brought together with the greatest exactness, and the whole of their surfaces be perfectly smooth. ; The mortising, tenoning, ploughing, and sticking of the mouldings, ought to be worked correctly to the gauge-lines otherwise the door, when put together, will be out of truth, and occasion the workman a great deal of trouble, paring the different parts to make it appear satisfactory: the door will also lose much of its firmness, especially if the mortises and tenons require to be pared. In bead and flush doors, make the work square, afterwards put in the panels, and smooth the whole off together; then, marking the panels at the parts of the framing to which they agree, take the door to pieces, and work the beads on the stiles, mountings, and rails. If the doors are double margin, that is, representing a pair of folding doors, the staff stile, which imitates the meeting-stiles, must be inserted into the top and bottom rails of the door, by forking the ends into notches cut in the top and bottom rails. In the hanging of doors, the chief aim is to clear the carpet or ground; which may be accomplished by observing the following rules. First, let the floor be raised under the door, according to the intended thickness of the carpet; secondly, let the knuckles of the top and bottom hinges be so placed, that the top hinge hang, or project, about one eighth of an inch over the lower; that is, if the hinge be let equally into the door and into the jamb, project a little beyond the surface of the door; but if the centre lie in the surface of the door, it must be placed at the very top, which is seldom done, except when the door is hung with centres. Thirdly, let the jamb on which the door hangs, be fixed about an eighth of an inch out of the perpendicular, the upper part inclining towards the opposite jamb; and fourthly, let the inclination of the rebate be such, that the door shall, when shut, project at the bottom, towards the room, about an eighth of an inch. These several methods, practised on so small a scale, are not perceptible; but, nevertheless, will throw the door, when opened, to a square sufficiently out of the level; that is, at least half an inch, when the height of the door is double the width. Several kinds of rising hinges have been introduced for this purpose some of the best, constructed of brass, are by no means objectionable, even to the best doors. Before we proceed to the principles of hanging doors, we shall submit to the reader some information on the subject of hinging in general. The placing of hinges depends entirely on the form of the joint, and as the motion of the door or closure is angular, and performed round a fixed line as an axis, the hinge must be so fixed that the motion be not interrupted: thus, if the joint contain the surface of two cylinders, the convex one in motion upon the edges of the closure, and sliding upon the concave one which is at rest on the fixed body, the motion of the closure must be performed on the axis of the cylinder, which axis must be the centre of the hinges. In this case, whether the aperture be shut or open, the joint will be close; but if the joint be a plane surface, it is necessary to consider upon what side of the aperture the motion is to be performed, as the hinge must be placed on the side of the closure where it revolves. The hinge is made in two parts, movable in any angular direction, the one upon the other. The knuckle of the hinge is a portion contained under a cylindric surface, and is common both to the moving part and the part which is at rest; the cylinders are indented into each other, and are made hollow to receive a concentric cylindric pin, which passes through them, and connects the moving parts together. The axis of the cylindrical pin, is called the axis of the hinge. When two or more hinges are placed upon a closure, the axis of the hinges must be in the same straight line. The straight line in which the axis of the hinges are placed is called the line of hinges. We shall now proceed to the principle of hanging doors, shutters, or flaps, with hinges. The centre of the hinge is generally put in the middle of the joint, as at A, Fig. 605, but in many cases there is a necessity for throwing back the flap to a certain distance from the joint; in order to effect this, suppose the flap when folded back, were required to be at a certain distance from the joint, as BA, Fig. 605, divide BA in two equal parts at the point C, and it will give the centre of the hinge. The centre of the hinge must be placed a small degree beyond the surface of the closure, otherwise it will not fall freely back on the jamb, or partition. It must also be observed, that, the centre of the hinge must be on the same side as the rebate, or it will not open without the joint being constructed in a particular form. To hang two flaps, so that when folded back, they shall be at a certain distance from each other. This is easily accomplished by means of hinges having knees project ing to kalf that distance, as appears from Fig. 607; this sort of hinge is used in hanging the doors of pews, in order to clear the moulding of the coping. Fig. 607, No. 2, shows the same hinge opened. To make a rule joint for a window-shutter, or other folding flap. Fig. 606, No. 1. Let a be the place of the joint, draw a c at right angles to the flap, shutter, or door, take c, in the line a c, for the centre of the hinge, and the plain part a b, as may be thought necessary; or c, with a radius, cb, describe the arc b d; then will a b d be the true joint. The knuckle of the hinge is always placed in the wood; because the further it is inserted, the more of the joint will be covered when it is opened to a right angle, as in Fig. 606, No. 2; but if the centre of the hinge were placed the least without the thickness of the wood, it would show an cpen. space, which would be a blemish. To form the joints of stiles, to be hung together, when the knuckle of the hinge is placed on the contrary side of the rebate. Fig. 608. Let c be the centre of the hinge, mi the joint on the same side, cb the depth of the rebate in the middle of the thickness of the styles, perpendicular to i m, and If the joint on the other side, parallel to im; bisect il at k, join k c, on k e describe a semicircle cik, cutting im at h, through the points h and k draw hk g, cutting flat g; then will ƒ g, h m, be the true joint. Fig. 609 represents the common method of hanging shutters together, the hinge being let the whole of its thickness into the shutter, and not into the sash-frame. By this mode it is not so firmly hung as when half of it is let into the shutter, and half into the sash-frame; but the lining may be made thinner. It may here be proper to observe, that the centre of the hinge must be in the same plane with the face of the shutter, or beyond it, but not within the thickness. How to construct a joint for hanging doors with centres. Fig. 614. Let a d be the thickness of the door, bisect it in b, draw be perpendicular to a b, make b c equal to b a, or bd, or c, the centre of the hinge, with a radius c a, or cd, describe an arc, a e d, which will give the joint required. Another plan is represented in Fig. 613. Draw a b parallel to the jamb, meeting the other side in b, make b d equal to ba, and join a d and a c, bisect a c by a perpendicular ef, meeting a d in f, then ƒ is the centre of the hinge. Figs. 610, 611, and 612, exhibit different methods of hanging flaps, &c. These are so very simple, that by a little attention the reader will readily perceive their uses and manner of construction. We shall now detail the construction of sash-frames, sashes, and shutters, and the manner of putting the several parts together. Fig. 615, No. I, the elevation; No. 2, the plan; and No. 3, the section of the same; showing the manner in which the different parts are connected. |