Let A (Fig. 246) be the wall of the building, and B the given bracket, which, for the present purpose, is turned down horizontally. The angle-bracket, C, is obtained thus: through the extremity, a, and parallel with the wall, fd, draw the line a b; make ec equal af, and through c draw cb parallel with ed; join d and b, and from the several angular points in B draw ordinates to cut db in 1,2, and 3; at those points erect lines perpendicular to db; from h draw kg parallel to fa; take the ordinates, 1 o, 2 o, etc., at B, and transfer them to C, and the angle-bracket, C, will be defined. In the same manner, the angle-bracket for an internal cornice, or the angle-rib of a coved ceiling, or of groins, as at Fig. 247, can be found.