Ionic order

The Ionic order forms one of the three classical orders of classical architecture, the other two canonic orders being the Doric and the Corinthian. There are two lesser orders: the Tuscan (a plainer Doric), and the rich variant of Corinthian called the composite order, both added by 16th-century Italian architectural writers, based on Roman practice. The Ionic columns are the thinnest and smallest columns out of the three canonic orders.

The Ionic capital is characterized by the use of volutes. The Ionic columns normally stand on a base which separates the shaft of the column from the stylobate or platform; the cap is usually enriched with egg-and-dart.

Since Vitruvius a female character has been ascribed to the Ionic, in contrast to the masculine Doric.

The major features of the Ionic order are the volutes of its capital, which have been the subject of much theoretical and practical discourse, based on a brief and obscure passage in Vitruvius. The only tools required to design these features were a straight-edge, a right angle, string (to establish half-lengths) and a compass. Below the volutes, the Ionic column may have a wide collar or banding separating the capital from the fluted shaft (as in, for example, the neoclassical mansion Castle Coole), or a swag of fruit and flowers may swing from the clefts or "neck" formed by the volutes.

Originally the volutes lay in a single plane (illustration at right); then it was seen that they could be angled out on the corners. This feature of the Ionic order made it more pliant and satisfactory than the Doric to critical eyes in the 4th century BC: angling the volutes on the corner columns ensured that they "read" equally when seen from either front or side facade. The 16th-century Renaissance architect and theorist Vincenzo Scamozzi designed a version of such a perfectly four-sided Ionic capital; Scamozzi's version became so much the standard, that when a Greek Ionic order was eventually reintroduced, in the later 18th century Greek Revival, it conveyed an air of archaic freshness and primitive, perhaps even republican, vitality.

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