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
Tuscan order largely motivated by nationalism. 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