Doric order The Roman architect Vitruvius, following contemporary practice, outlined in his treatise the procedure for laying out constructions based on a module, which he took to be one half a column's diameter, taken at the base. An illustration of Andrea Palladio's Doric order, as it was laid out, with modules identified, by Isaac Ware, in "The Four Books of Palladio's Architecture" (London, 1738) is illustrated at Vitruvian module. According to Vitruvius the height of Doric columns is six or seven times the diameter at the base. This gives the Doric columns a shorter, thicker look than Ionic columns, which have 8:1
Corinthian order colonettes within the same system. During the 16th century, a sequence of engravings of the orders in architectural treatises helped standardize their details within rigid limits. Sebastiano Serlio; the "Regola delli cinque ordini" of Giacomo Barozzi da Vignola (1507–1573); the "Quattro libri di Architettura" of Andrea Palladio, and Vincenzo Scamozzi's "Idea della Architettura Universale," were followed in the 17th century by French treatises with further refined engraved models, such as Perrault's. Corinthian order The Corinthian order is the last developed of the three principal classical orders of ancient Greek and Roman architecture. The other two are the Doric order which