The Ionic entablature can be divided into 18 parts to derive the heights of its main components. The cornice is 7 parts (7/8 D), the frieze is 6 parts (6/8 D), and the architrave is 5 parts (5/8 D). The total height of the entablature is 2 D.
The cornice projects out from the entablature 7/8 D, which is the same dimension as its width. Like the mutulary Doric Order, the cymatium consists of a large cyma recta followed by a smaller cyma reversa. The corona sits below the cymatium and should be undercut with a drip to soften the appearance of its underside and protect the building faĆ§ade from water.
A large bed mold with an ovolo, dentils, and a cyma reversa sits below the corona. To determine the location of the ovolo in relation to the corona, one can first draw the dentils starting with the one centered above the column. Each dentil is 1/6 D high by 1/9 D wide. The space between dentils, or interdentil, is 1/18 D so that the width of the dentil plus the interdentil equals 1/6 D. The rightmost of the dentils is a double dentil without a space which indicates the dentil as it turns the corner. Above the projection of the fillet of the double dentil is the start of the ovolo.
The frieze is often straight but sometimes pulvinated, or bowed. A 60 degree equilateral triangle defines the pulvination and is shown as a dashed line.
The architrave has an upper and lower fascia. At the top of the upper fascia is a fillet and cyma reversa which projects from the architrave the same dimension as its width. The upper fascia is wider that the lower one. A small ovolo and fillet separates the two fascias.
Text: Martin Brandwein Rendering: M. Gunnison Collins