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
Ancient Greek architecture order co-existed with the Doric, being favoured by the Greek cities of Ionia, in Asia Minor and the Aegean Islands. It did not reach a clearly defined form until the mid 5th century BC. The early Ionic temples of Asia Minor were particularly ambitious in scale, such as the Temple of Artemis at Ephesus. The Corinthian Order was a highly decorative variant not developed until the Hellenistic period and retaining many characteristics of the Ionic. It was popularised by the Romans. The Doric order is recognised by its capital, of which the "echinus" is like a circular cushion rising from