strength to support the stairway and its probable load, rough brackets being nailed on the sides of these scantlings and fitted tightly under each tread, as shown at a, Fig. 2Fig. 2. Rough brackets being nailed on the sides of these scantlings and fitted tightly under each tread. . In some cases, where the treads and risers are enclosed in stringers, the wall stringer only is housed to receive the treads and risers, the front, or outer, stringer being cut square to receive the tread, and mitered to receive the riser. When thus prepared the front stringer is termed a <STRONG >cut-and-mitered</STRONG>, or <STRONG >open</STRONG>, stringer, the wall stringer being termed a <STRONG >housed</STRONG> stringer. Occasionally both wall and front stringers are housed, in which case the front stringer is said to be a close stringer. Geometrical stairways are seldom thus constructed, the method being mostly confined to dog-leg and open-newel stairways.
In geometrical stairways, the front stringer is cut and mitered so as to meet the conditions arising from the wreathed portion of the stringer and rail, which are assumed to stand perpendicular to each other and in the same vertical plane. The rail in this case is wholly supported by the balusters, instead of by the newel, and the cut-and-mitered stringer affords a substantial footing to the balusters, which are dovetailed, glued, and nailed to the ends of treads; the nosing and molding of the treads being returned their full width on the face of the stringer. Stairs thus constructed are said to have nosed and mitered moldings, and when brackets are placed along the front stringer below the nosing, the stairway is known as a <STRONG >bracketed stairway</STRONG>.
6. <STRONG >Height of Risers</STRONG>. — In setting out a stairway, the first consideration should be to ascertain the exact height between the floors, the height to be measured from the top of the floor below to the top of the floor above. For this