ARCHITECTURAL ORDERS. — The system of load-bearing architectural elements (column and capital) and those borne (entablature), which already appears in Assyrian, Egyptian, and other pre-classical architectures, is defined by Greek art through particular forms and proportions in the main members and their parts, thus characterizing the various orders; above all, the capital is the determining element. The fundamental orders are the Doric and the Ionic, which developed simultaneously between the 7th and 6th centuries B.C.; from these others derive.
A first definition, along with legendary accounts of their origin, is given by Vitruvius; the orders are then codified by 16th-century theorists such as Serlio, Vignola, Palladio, and Scamozzi; and in the Neoclassical age particularly by Milizia. Among these theorists there is no complete agreement on the proportions and relationships of the elements of each order, which are established according to the particular sensibility of the author and the monuments examined.
The Doric order is the one that most emphasizes the structural function of its members; the shaft of the column (which in its most archaic form rises directly from the ground) has a height of about 8 diameters, and is fluted with sharp arrises (first 16 to 24 flutes, then in the Classical age 20); the capital is simply composed of an echinus and an abacus; in the frieze of the entablature, metopes (smooth slabs or adorned with low reliefs, generally figured) and triglyphs (slabs adorned with vertical flutes that perhaps preserve the memory of wooden support elements) alternate. A variation of this order, with a smooth shaft and an architrave lacking a frieze, is called Tuscan or Etruscan because it is considered characteristic of the Etruscan period.
More slender is the Ionic order, in which the column has a height, first of 8 then about 9 diameters, and has a shaft with chamfered flutes; the capital is characterized by two volutes; the entablature is distinguished by an architrave subdivided into various bands and by a frieze, smooth or adorned with continuous decoration.
From the Ionic order the Corinthian develops, which differs from it by a greater slenderness (the height of the column is about 10 diameters) and above all by the greater elegance of the capital, decorated with a double row of acanthus leaves. From this the Composite order differs only in the form of the capital, which superimposes upon the acanthus the volutes of the Ionic order and is also adorned with figured elements.
It is also necessary to recall the so-called figurative order (or, according to Milizia, Caryatic or Persian), in which human figures replace columns in their load-bearing function; but the name of "order" is in this case improper, inasmuch as its proportions escape every rule.
Early Christian architecture sometimes systematically employs the orders, as in the interior of S. Giovanni in Florence or the Lateran Baptistery (Corinthian); in S. Maria Maggiore in Rome a long row of Ionic columns, reworked during the 18th century, supports a decorated entablature. But soon, with the use of spolia, the elements that define the orders are confused, as in S. Salvatore in Spoleto, where Corinthian columns support a Doric entablature; then throughout the Middle Ages the arch definitively prevails over the entablature, which reappears in the Romanesque period in Lazio, where the classical tradition was more alive and examples more numerous: in the colonnades of S. Maria in Trastevere or in the Cosmatesque porticos of some churches, Ionic capitals, ancient or carefully imitated, are used, upon which runs an undecorated or musically decorated entablature, in imitation of that of S. Maria Maggiore. This attempt at classical revival is, however, entirely sporadic.
Only in the 15th century, with the passionate study of antiquity, does the use of the orders return and become ever more firmly established, until it becomes a fundamental compositional element of European architecture. The proportions and forms escape pre-established canons; classical modes are reflected, sometimes intimately re-experienced but sometimes transformed by the architect’s personality or by new aesthetic trends; often the order is defined only by the type of capital, itself whimsically varied in decoration.
The first expressions appear in Tuscany with Brunelleschi, who adopts the Corinthian order on the exterior and interior of the Pazzi Chapel and in the Old Sacristy of S. Lorenzo; and, with a more solemn classical sense, with Leon Battista Alberti in the Malatesta Temple in Rimini (in
The unfinished façade is a first example of the superimposition of orders, as seen in S. Maria Novella in Florence and in S. Andrea in Mantua; Alberti himself codifies the return to the Roman norm of the subsequent superimposition of orders (from the Doric at the bottom, Ionic, and Corinthian above) in the Palazzo Rucellai in Florence. Outside Florence, this usage is not yet clearly defined, as seen in the Arch of Alfonso of Aragon in Naples, where, despite the strong classical inspiration, the Ionic order is superimposed on the Corinthian.
In numerous churches of the second half of the 15th century, the same order (mostly Corinthian) is used in the two zones of the façade, with varying proportions and projections so flat as to express only a division of space (S. Maria del Popolo and S. Agostino in Rome; the Duomo of Turin; S. Francesco in Ferrara; S. Pietro in Modena; etc.); instead, in the Albertian façade of S. Marco in Rome, the superimposed orders are expressed with clear functional value and classical sense of proportion.
At the beginning of the new century, Bramante, with the Tempietto of S. Pietro in Montorio, makes use of the Doric order, with perfect correspondence of forms and rhythm between exterior and interior. A similar unity of composition is achieved by Antonio da Sangallo the Elder in S. Biagio in Montepulciano, where the Doric order is also the dominant motif.
The most frequent scheme in the façades of 16th-century churches is that of two superimposed orders, not according to the classical Albertian conception, but following instead the prototype of S. Spirito in Sassia, i.e., with the use of the Corinthian in both zones. There are exceptions to this arrangement, with the adoption in the lower zone of the Doric order (S. Giacomo in Augusta in Rome; S. Paolo in Milan); or Ionic (S. Maria dell'Orto in Rome; S. Giorgio in Bologna; Scuola di S. Fantin in Venice); or finally, superimposing Doric and Ionic (Annunziata in Parma; S. Giuliano in Venice; S. Sebastiano in Milan). But in the design for the façade of S. Pietro, Michelangelo adopts a single order (Corinthian), which extends to the sides and the tribune, reappears in the dome, dominates the interior, with perfect unity among all parts. Palladio also arrives at the same conception of a single order in the façades (repeated in the interior), drawing direct inspiration from ancient temples; the greatest examples are the Redentore and S. Giorgio Maggiore in Venice. The single order continues into the Baroque period, generally with little plastic sense (S. Francesca Romana, SS. Pietro e Marcellino, S. Croce in Gerusalemme in Rome; S. Firenze in Florence; S. Maria di Carignano in Genoa), though sometimes achieving vivid pictorial effects through the power of projections, as in S. Giovanni in Laterano, and especially in Venice, where the Palladian tradition endures (S. Maria della Salute).
The orders are adopted—quite apart from the architectural motif of the church—not only in accessory spaces such as sacristies, but also in chapels, whether as independent additions (among the first examples is the Raphael-designed Chigi Chapel in S. Maria del Popolo) or as part of a unified conception; this is the case in the majority of 17th-century chapels (a typical example is S. Andrea della Valle in Rome, where each chapel employs the order with distinct characteristics).
Even in the various furnishings of churches—altars, ciboria, tabernacles, pulpits, lavabos (v. the individual entries), frames of altarpieces—and in funerary monuments, the orders have been used since the Renaissance, reflecting the successive forms of major architecture.
As for the so-called figurative order, a first expression can be traced to Michelangelo’s design for the tomb of Julius II. This invention was well received by the Mannerists, who would adopt it in civil architecture, and above all in villas or decorative elements. In church façades, a first limited application is found in S. Maria di S. Celso in Milan, by Alessi; more complete examples are in S. Raffaele in Milan, and, in the Baroque period, in the Ospedaletto in Venice and the national church in Trapani. Among applications in interiors, notable is that of the Oratory of S. Zita in Palermo. A rare example of figurative order in bell towers is the Borrominian one of S. Andrea delle Fratte in Rome. — See pl. XIV.