Page:EB1911 - Volume 15.djvu/508

Rh is guided into position by the edges working in metal grooves a little under an inch wide. When the width of the opening to be closed renders it necessary to divide the shutters into more than one portion, grooved movable pilasters are used, and when the shutters have to be lowered these are fixed in position with bolts, the shutter working on the grooved edges of the pilasters. Spring roller canvas blinds work on a similar principle. The wrought-iron blind arms are capable, when the blind is extended, of being pushed up by means of a sliding arrangement, and fixed with a pin at a level high enough to allow foot passengers to pass along the pavement under them.

Doors.—External doors are usually hung to solid frames placed in the reveals of the brick or stone wall. The frames are rebated for the door and ornamented by mouldings either stuck or planted on. The jambs or posts are tenoned, wedged and glued to the head, and the feet secured to the sill by stub tenons or dowels of iron. Solid window frames are of similar construction and are used chiefly for casements and sashes hung on centres as already described. Internal doors are hung to jamb linings (fig. 7). They are usually about 1 in. thick and rebated for the door. When the width of jamb allows it, panelling may be introduced as in the example shown. The linings are nailed or screwed to rough framed grounds 1 in. in thickness plugged or nailed to the wall or partition. Architraves are the borders or finishing mouldings fixed around a window or door opening, and screwed or nailed to wood grounds. They are variously moulded according to the fancy of the designer. The ordinary form of architrave is shown in the illustration of a cased window frame (fig. 8), and a variation appears in the combined architrave and over door frieze and capping fitted around the six-panelled door (fig. 7). The latter would need to be worked and framed in the shop and fixed entire. Polished hard wood architraves may be secretly fixed, i.e. without the heads of nails or screws showing on the face, by putting screws into the grounds with their heads slightly projecting, and hanging the moulding on them by means of keyhole slots formed in the back.

Doors may be made in a variety of ways. The simplest form, the common ledged door, consists of vertical boards with plain or matched joints nailed to horizontal battens which correspond to the rails in framed doors. For openings over 2 ft. 3 in. wide, the doors should be furnished with braces. Ledged and braced doors are similar, but have, in addition to the ledges at the back, oblique braces which prevent any tendency of the door to drop. The upper end of the brace is birdsmouthed into the under side of the rail near the lock edge of the door and crosses the door in an oblique direction to be birdsmouthed into the upper edge of the rail below, near the hanging edge of the door. This is done between each pair of rails. Framed ledged and braced doors are a further development of this form of door. The framing consists of lock and hanging styles, top, middle and bottom rails, with oblique braces between the rails. These members are tenoned together and the door sheathed with boarding. The top rail and styles are the full thickness of the door, the braces and middle and bottom rails being less by the thickness of the sheathing boards, which are tongued into the top rail and styles and carried down over the other members to the bottom of the door. The three forms of door described above are used mainly for temporary purposes, and stables, farm buildings and outhouses of all descriptions. They are usually hung by wrought-iron cross garnet or strap hinges fixed with screws or through bolts and nuts.