In Fig. 392, C B D represents a portion of the elevation of what is known as a "broken pediment," the normal profile of whose cornice is shown at A1. With these conditions existing it becomes necessary-to obtain new profiles for the returns at both the top And the foot. The method of raking the return at the foot has been described in Problem 91, and the method of raking the return at the top is exactly the same. If, in the designing of the pediment, the normal profile should be placed in the return at the foot, as its sometimes necessary, then the profile of the inclined molding must be first obtained, which in turn must be considered as a normal profile and used as a basis of obtaining the third profile, that of the return at the top.

In Fig. 392, let A1 be considered as the normal profile of the inclined molding. Divide A1 into-any convenient number of parts in the usual manner, and through these points draw lines parallel to the lines of the cornice indefinitely. At any convenient point outside of the cornice, and in a vertical line with the point at which the new profile is to be constructed, draw a duplicate of the profile of the raking cornice, as shown by A, which space into the same number of parts as A1, already described. From the points in A draw lines vertically, intersecting lines drawn from A1. Then a line traced through these several points of intersection, as shown by A", will constitute the profile of the horizontal return at the top and also the miter line as shown in elevation. If the normal profile were in the horizontal return at the foot of the pediment and the modified profile in the position of A1, it would be immaterial whether the normal profile or a duplicate of the modified profile were in the place of A by which to obtain the intersecting lines, as the projection of the points only is to be considered in this operation, and that is the same in both cases.

For the pattern of the inclined molding proceed as follows: At right angles to the lines of the raking cornice lay off a stretchout of the profile of the raking cornice A1, as shown by F G, through the points in which draw measuring lines in the usual manner. Place the T-square at right angles to the lines of the raking cornice, and, bringing the blade successively against the points in the profile A3, which is the miter line in the elevation, cut the corresponding measuring lines, and through these points of intersection trace a line, as. shown by G H. Then G H will be the pattern of the top end of the raking cornice to miter against the horizontal return. For the pattern of the horizontal return the usual method would be to construct an elevation of it in a manner similar to that described for the return at the foot of the gable in the preceding demonstrations; the equivalent of this, however, can be done in a way to save a considerable portion of the labor.

As the view of the miter line is the same in both the front and the side elevation the pattern may be developed from the front just obtained in the following manner, with the result, however, that the pattern will be reversed: Draw the line K M perpendicular to the lines of the horizontal return, as it would be if shown in elevation. Upon K M lay off a stretchout of the profile A2, all as shown by the small figures, and through the points draw the usual measuring lines. With the T-square parallel to the stretchout line K M bring the blade successively against the points in the profile A2, cutting the corresponding measuring lines. Through these points of intersection trace a line, as shown by N L, which will be the pattern of the end of the horizontal return to miter against the gable cornice, as shown.

Fig. 392.   To Obtain the Profile of the Horizontal Return the Top of a Broken Pediment Necessary to Miter with a Given Inclined Molding, and the Patterns of Both.

Fig. 392. - To Obtain the Profile of the Horizontal Return the Top of a Broken Pediment Necessary to Miter with a Given Inclined Molding, and the Patterns of Both.