ornamental ironwork: The shaping of wrought iron, used almost exclusively until the 16th cent., is primarily an art of the blacksmith, who must work with the metal while it is at the desired stage of heat and flexibility. Methods and tools used in modern hand-wrought work are similar to the early ones. However, much modern work is accomplished by mechanical means, with the pneumatic hammer and the acetylene or electric torch. A variety of stock pieces are currently available that the early smith had to fashion laboriously from crude ingots. Iron was used ornamentally in classical times. Because of rusting and the decay of the material, little survives of very early work. Door hinges, generally C- or S-shaped, still exist from the 12th cent. In the 13th cent. vine scrollwork on hinges and grilles replaced the earlier patterns. In succeeding periods, wrought-iron designs assumed the forms of other architectural decoration: Gothic tracery, plant forms, classical motifs, rococo broken curves, and delicate neoclassical work. In Spain the iron grille attained a high development (see rejería). In France in the mid-17th cent. a vogue developed for iron balconies, stair railings, and monumental fences and gateways, rich with scrollings and bold foliations. This style was transplanted to England c.1700 by Jean Tijou. In American work of the 18th cent. simplicity and restrained ornamentation prevailed. Cast iron was rarely used prior to the 16th cent., when it came into demand for andirons and firebacks. For architectural embellishment and for garden furniture it became common in the early 19th cent. It was used extensively for fences and railings in the S United States. Since cast iron is cheaper and more rigid than wrought iron and is less affected by corrosion than any other cheap commercial iron, it has been widely used during the last three centuries. Modern sculptors who have worked in iron include Julio González, Picasso, and David Smith.

See G. K. Geerlings, Wrought Iron in Architecture (new ed. 1957); F. Kühn, Wrought Iron (2d ed. 1969); T. Menten, Art Nouveau Decorative Ironwork (1981).

iron. Widely used in architecture. There are two basic types: cast iron, which is strong in compression, but weak in tension, so is used for columns, bollards, railings, and decorative features; and wrought iron, which is employed for gates, ornamental scrolls, filigree-work, and the like. Some fine medieval ironwork survives, notably associated with English tombs and chantry-chapels in cathedrals and churches. Later, iron was widely used for balcony-fronts, railings, etc., in C18. Exposed cast iron was used for components in whole façades in C19, notably by John Baird in Glasgow, and wrought iron was used to construct large trusses spanning wide spaces. There are many C19 catalogues of cast-iron components, notably by Badger in the USA and the Saracen Factory, Glasgow. Fairbairn's On the Application of Cast and Wrought Iron to Building Purposes (1854) was an important publication. Iron-and-glass structures were developed for conservatories, railway-stations, exhibition-buildings, and the like, notably by Paxton, Loudon, and others. Iron was used structurally, starting with late-C18 bridges such as at Coalbrookdale, Salop. (1777–9), Sunderland (1793–6), and Buildwas, Salop. (1795–6), and then for factories and warehouses, notably at William Strutt's Mill, Derby (1792), and the Marshall, Benyon, & Bage Mill, Shrewsbury, Salop. (1796), both of which had cast-iron columns carrying systems of beams from which sprang brick vaults. Developments in iron structures occurred when composite girders and columns were made, using rivets, and gradually framed buildings were evolved, permitting speed of erection, great heights, and light claddings. Ultimately, the steel frame permitted the building of skyscrapers. See also metal structures.

Bibliography

Fairbairn (1849, 1869, 1870);
Fairbairn & and Pole (1970);
Gayle & and Gillon (1974);
G. Hartung (1983);
Lemoine (1986);
Loudon (1834);
Mainstone (1975);
Sturgis et al. (1901–2)