Ionic style doorways
the height of the aperture should be reached in the same manner as in the Doric. Let its width be determined by dividing the height into two and one half parts and letting one of them form the width at the bottom. The diminutions should be the same as for Doric. The width of the faces of the jambs should be one fourteenth of the height of the aperture, and the cymatium one sixth of the width. Let the rest, excluding the cymatium, be divided into twelve parts. Let three of these compose the first fascia with its astragal, four the second, and five the third, the fasciae with their astragals running side by side all round. The cornices of Ionic doorways should be constructed in the same manner as those of Doric, in due proportions. The consoles, otherwise called brackets, carved at the right and left, should hang down to the level of the bottom of the lintel, exclusive of the leaf. Their width on the face should be two thirds of the width of the jamb, but at the bottom one fourth slenderer than above. (Vitruvius, 15BCE)