BRACKETING, a disposition of small pieces of board, equidistantly placed in the angles formed by the ceiling and the walls of an apartment, with their planes at right angles to the common intersection, so as to be partly upon the veil ing and partly upon the walls; their faces or hedges being so arranged, as to touch any level line that is everywhere equally distant from the wall or walls which may firm the perimeter or circumference of the apartment. The level line equi distant from, or parallel to the walls, will either be a straight line or curve, according as the walls are carried upwards from a straight or circular plan.
Bracketing is necessary in supporting the lath and plaster of cornices and coves. The edges of the brackets to which the lath is fixed, arc so formed as to he as nearly equidistant from the surface of the intended cornice or cove as poFsible, and may be placed about an inch within the said surface. Their common distance from middle to middle may be about a foot or finirteen inches. Small cornices require no brackets; hut in large cornices, and particularly in coves, they are indispensably necessary, to save the plaster. In apartments formed by walls with plain surfaces, besides the brackets which are arranged at right angles to the line of concourse of the ceilings and the walls, there are other brackets placed, one in each angle, in a vertical plane, bisecting the angle formed by each two adjacent sides of the room, at the mitre of the cornice., denominated angle-brackets.
Let Fig. 1 be the plan of the end of the room, the internal side being A rt ennFo it, and let there be a break, c n F, • as the breast of a chimney. Let Fig. 2 be part of the plan enlarged, showing an internal angle at c, and an external angle at n : let Nor o represent the face of the rough wall, and a c a x the finish of the plaster ; then the space between N o and a c, o r, and c n, r o and a E will be the space for the battening, lath, and plaster. Let Fig. 3 he a section of the cornice, intended to be run by the plasterer, and let the shadowed part be the form of the common brackets: let I K, I lc, &c., Fig. 2, be the projections or seats of the common brackets, each equal to A n, Fig. 3, and let L o and n r he
the scats of the angle-bra•kets; T. o being that of the internal bracket, and sI P that of the external bracket. Besides the projection beyond the finishing surface of the plaster, there must be added the thickness of the battening, lath, and plaster. As the lath terminates upon the angle-brackets, and as they require to be ranked in the same surface with the edges of the common brackets, they are here made double, or in two thicknesses. Let it now be required to find the form of the brackets, either for mouldings, as Fig. 8, or for a cove: make A 11, Figs. 4 and 5, equal to the projection , of the common bracket; draw rt b perpendicular and equal to A B, and join A G: place or draw the fluln of the bracket with the ceiling edge of it upon A : take any number of points, 0, n, r, K, &c., in the ranging edge of the bracket, at the concourse of every two lines, or in the curve, and draw G A, n C, r re E, perpendicular to A II: prialnee n C, I I), K E, &C., to meet A It in c,d,e, &c... draw A rj,c It, d i, e k, &e., perpendicular to A b, and MAC A 9, C d e k, &c., each equal to x c, e m, D I. E K. eke., and join the points y, i, &e. if the ranging edge of the common bracket is made of straight lines ; or draw a curve if the common bracket is a cove : then Will A 9, b, &c. to 11, be the fOrm of the angular bracket. whether for the external or internal angle, and y, It, i, k. &e., the ranging edge; the parts e n and y h are supposed to be within the finished surface of the plaster. Fig. 6 shows the bracket for an acute angle, and Fig. 7 for an obtuse angle ; but except the quantity of the angle, the method of finding the forms is exactly the same as in Figs. 4 and 5. The bracket of Figs. 4, 5, and 7, is laid down upon the ceiling line ; but that of Fig. 6 is laid down upon the base line. 111 the common brackets of Figs. 5 and 6, the projections and heights are equal ; but in Fig. 7, the height D c is greater than the projection A a : the shadowed parts ef Figs. 11 and 1" represent the thickness of the batten ing. lath. and plaster. Figs. S, 11, 10, 11, show the ranging both for external and internal angles. See RANGING.