Tuscan order

The Tuscan order is in effect a simplified Doric order, with un-fluted columns and a simpler entablature with no triglyphs or guttae. It was not one of the three orders of classical architecture described by the Roman architect Vitruvius; these were the Doric, Ionic, and Corinthian. Instead the Tuscan order, presented as a standardized formal order, is an invention of Italian Renaissance writers largely motivated by nationalism. However, relatively simple columns with round capitals had been part of the vernacular architecture of Italy and much of Europe since at least Etruscan architecture.

Sebastiano Serlio described five orders including a "Tuscan order", "the solidest and least ornate", in his fourth book of Regole generali di architettura sopra le cinque maniere de gli edifici (1537). Though Fra Giocondo had attempted a first illustration of a Tuscan capital in his printed edition of Vitruvius (1511), he showed the capital with an egg and dart enrichment that belonged to the Ionic. The "most rustic" Tuscan order of Serlio was later carefully delineated by Andrea Palladio.

In its simplicity, The Tuscan order is seen as similar to the Doric order, and yet in its overall proportions, intercolumniation and simpler entablature, it follows the ratios of the Ionic. This strong order was considered most appropriate in military architecture and in docks and warehouses when they were dignified by architectural treatment. Serlio found it "suitable to fortified places, such as city gates, fortresses, castles, treasuries, or where artillery and ammunition are kept, prisons, seaports and other similar structures used in war."

Not all modern writers accept the Tuscan order, and it is sometimes called "Doric" even by those aware of the distinction.

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