75. It is sometimes desirable to erect small structures entirely of cast and wrought iron. Of these the most common are the small domes or cupolas crowning the roofs of certain classes of buildings, bay windows, oriole windows, and show windows for residences and stores, and occasionally small detached buildings used as offices for the sale of tickets at the entrance of places of amusement, or as an adjunct to some branch of a general service system, as is the example hereafter shown. In any case, the structure is necessarily of an ornamental character, and must accord in design with surrounding conditions.

An example of a detached iron structure is shown in Fig. 105. The entire edifice being constructed of cast and wrought iron framework carrying a copper roof and heavy plate-glass window lights. The purpose of the building is that of a cab office in connection with the service of a hotel, club, or theater. The plan is octagonal, as shown in Fig. 10G, each angle of the octagon being marked by a hollow cast-iron upright, molded to form the architraves of the window and door openings, and at the same time to contain the T-iron supports d of the roof and superstructure. These supports extend to the ground in each case, and stand upon an iron plate, or shoe, as shown at g in the elevation, Fig. 105 (a), and between them is framed an angle iron, to receive the ends of the floorbeams, as shown at l in the section, Fig. 105 (b). The space from this angle to the ground is filled with a cast-iron grille, as shown in the elevation at c; while from the floor to the window level a cast-iron plate encloses each side of the octagon with an ornamental panel p.

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Fig. 106.

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Fig. 106.

The construction of this paneled dado can be better understood from Fig. 107, which is a section taken on the line a b of Fig. 105 (a). The angle iron framed between the vertical T's, as shown at l in Fig. 105 (b), is here seen in section as piece + 32, and outside of it is the cast-iron facing of the structure, consisting of a water-table 4 inches in height, and the plinth, panel, and window sill extending 2 ft. 3 in. more. The sill cap o is secured at each end to angle-iron knees or brackets previously riveted or bolted to the vertical T supports. These sill caps extend over the top of the panel pieces and hold the latter in place by clamping over a rib piece cast on the top of the main panel. On this sill piece o rests the sash as shown at v, and on the inside of the office is secured the wood trim which forms the finish under the sill.

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Fig. 107.

76. In Fig. 108 is shown a section through the cornice on the line cd of Fig. 105 (a). This cast-iron cornice is fastened at each end to the T-iron uprights with screw bolts, and thereby braces and secures these uprights at top. The inside cornice r is secured in place by means of the wrought-iron strap s bolted to the main cornice, and to which the inside cornice is fastened with screw bolts. Observe that these screw bolts do not pass through the sash head, but simply secure the two pieces of cast-iron cornice to the strap or bar s.

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Fig. 108.

In Fig. 109 (a) is shown a section through the lower part of the cornice where the sash is intended to be immovable.

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Fig. 109.

The inside or lining strap is omitted in this case, and the outside cornice secures the top of the sash with a round-headed screw bolt, while the inside cornice is secured to the sash head by a countersunk screw bolt, the sash head serving the same purpose here as did the strap piece s in Fig. 108. At the door opening, the lower fillet of the inside cornice is omitted, thus permitting the outside cornice to fall below it and form a stop, for the top of the door, as shown in Fig. 109 (6). An inside strap or bar s is then used to screw these cornices to, for the preservation of their alinement, while the ribs t cast on the exterior cornice maintain it in its proper position as a door stop.

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Fig. 110.

77. The door frame is formed of two angle irons, whose legs are unequal, as shown in Fig. 109 (b). This inequality permits the inside angle to extend beyond the exterior one, and strike (when the door is closed) against the door stop formed in the architrave or jamb casting.

Fig. 110 shows three sections through the architraves and supporting T irons of the main frame. At (a) is shown a section through the architraves of the fixed sashes, where the glass of the windows is held in place by a molding and recessions in the casting. At (b) the section shown is through the architrave at one side of the door, where provision is made in the casting for the door stop against which the longer-legged angle iron of the door frame shall strike, and at (c) is shown a section through the architrave at the side of a pivoted window sash. The glass is here shown secured in the cast-iron sash frame similar to that in Fig. 108, except that in this case a rebate is cast in the frame and jamb against which the sash may strike when closed, and thus be prevented from revolving past the architrave.

78. The roof is framed with light angle irons bent to the form shown in the elevation, Fig. 105, and covered with copper on the outside; while the inside or ceiling is plastered on wire lath. The cresting around the eaves is of simple strap iron, a detail of which is shown in Fig. 111. The clock face is framed in a cast-iron ring with ornamental scrolls as shown, the details being similar to other cast-iron ornament of this character heretofore described.

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Fig. 111.