upon the nosing; fig. 3, the raking-mouldings, found as in fig. 1, pl. XLIX. Figure 4 shows the same thing, when the mouldings are to be placed around an internal space.

58. Figure 5, plate L, represents raking-mouldings for angle-bars of shop-fronts: abcd, &c. is the given moulding. Take any number of points, a, b, c, d, &c., in the curve, and draw lines, aa', bb', cc', dd', &c., parallel to the face of the window; draw a line k' i' perpendicular to the mitre line. Then, through the points a, b, c, d, &c., draw lines perpendicular to the line of the face of the window, cutting it at the points e, f, g, h, i. Transfer the distances between the points e, f, g, h, i, to the line k'i', which is drawn perpendicular to the mitre-line, at e',ƒ', g', h', i'; then draw lines parallel to the mitre-line, cutting the lines drawn parallel to the front at the points a', b', c', d', &c., and, through the points, a', b', c', d', &c., draw a curve, and it will form one side of the angle-bar: then, making the other similar, the whole angle-bar will be formed.

Figure 6 shows another design of a bar, where the window returns at an obtuse angle. The method of forming the angle-bar is the same as in fig. 5.

HINGING, AND THE FORMATION OF JOINTS.

59. A considerable degree of care is necessary to hang a door, a shutter, or any other piece of work, in the best manner. With regard to the hinge, the pin should be perfectly straight and cylindrical, and the parts accurately fitted together.

The hinges should be placed, so that their axes may be in the same straight line; as any defect, in this respect, will produce a considerable strain upon the hinges every time the door or shutter is moved, and it not only prevents it moving freely, but is also very injurious to the hinges.

60. In hanging doors, centres are often used instead of hinges; but on account of the small quantity of friction in centres when they are well made, a door moves too easily, or so that a slight draught of air accelerates it so much in falling to, that it shakes the building, and is disagreeable. We have seen this, in some degree, remedied, by placing a small spring to receive the shock of the door. The greatest difficulty, in hanging doors, is to make them to clear a carpet, and yet shut close at the bottom. To do this, that part of the floor which is under the door, when shut, may be made to rise about a quarter of an inch above the general level of the floor; which, with placing the hinges so as to cause the door to rise a little as it opens, will be sufficient, unless the carpet should be a very thick one.

Several mechanical contrivances have been used for either raising the door, or making a part to spring close to the floor, as the door shuts.

The latter is much the better method. But, by attention to rise the floor, and hinging the door properly, these contrivances are rendered of little value, while, when they are resorted to, they are seldom long in order.

61. Various kinds of hinges are in use. Sometimes they are concealed, as in the kind of joints called rule-joints; others project, and are intended to let a door fold back over projecting mouldings, as in pulpit-doors: when hinges project, the weight of the door acts with an increased leverage upon them, and they soon get out of order, unless they be strong and well fixed. 6%. The different objects to be attained by hinges will be best illustrated by examples.

Figure 1, plate LI, exhibits the METHOD of HINGING ONE FLAP TO ANOTHER, the joint being what may be termed a lap-joint, and is usually employed for shutter-flaps. The centre of the hinge is placed opposite to the joint.

When one flap revolves upon another, it is often required that the edge of the flap, when folded close upon the back of the other, shall be at a given distance from the joint: to do this, the centre of the hinge must be placed at half that distance from the joint: this is exemplified in fig. 2.

63. Figure 3 SHOWS the METHOD of HINGING a RULE-JOINT, the axis of the hinge being in the axis of the cylindric surface that forms the rule-joint.

Figure 4 shows the joint when open.

This method is sometimes used in window-shutters, but chiefly in tables and other furniture. If one of the straps of the hinges were cranked a little, as shown by fig. 5, these joints would be much less difficult to form. With the common hinges, it is usual to make the joint extend a little further than the quadrant of a circle, which renders it difficult to make the parts fit well when the joint is open.

Hinging Doors and Shutters.

64. Figure 6 shows a hinge for a door to open so as to fold flat back against an architrave, or other moulding. The dotted lines show the door when open; and the centre of the hinge should be at half the quantity of projection from the face of the door.

65. Fig. 7 shows the case where the hinge of a flap is on the reverse side of the rebate from the usual one. In such cases, we are often required to fold back the flap to a given place. Let us suppose from A it is to fold to B. Then, join AB, cutting the lines of the flaps at C, which is the proper place for the centre of the hinge. To find the bevels, on AC, as a diameter, describe a semicircle. Draw AD at any angle that may be esteemed convenient for the oblique portion of the joint, join DC, and set off Aa for the depth of the rebate, then draw a b parallel to AD; and bd perpendicular to the face of the flap, which will complete the joint Aabd.

66. Plate LII, fig. 1, Nos. 1 and 2, represents the form of the joint of two stiles, in order to fit each other. No. 3 shows the same when hinged together.

Figure 2, Nos. 1 and 2, exhibits a plane-joint, beaded alike on both sides: No. 3 shows the same when hinged together.

Figure 3, Nos. 1 and 2, exhibits the same thing with a double-lapped joint. No. 3 shows the two parts put together.

Figure 4, Nos. 1 and 2, shows the same thing, with a single lapped-joint. 67. Figure 5 exhibits the manner of hinging a shutter to the sash-frame.

Figure 7 shows the method of hinging shutters, so as to conceal the hinges.

68. Figure 6 exhibits the manner of hanging a door upon centres. If the door has any mouldings which project a bead, A, or other moulding, should be formed of sufficient thickness for the door to open square, and yet the mouldings on it not touch the jamb. To find the place for the centre make CB, its distance from the line of the jamb, about a sixteenth of an inch more than CD, which is half the thickness of the door. In doors, for principal rooms, a moulding is formed on each side of the stile, as shown by the dotted lines, to prevent the joint from appearing open when the door is open.