The style of carving of the cymatium with its astragal should be the Lesbian.
Its cymatium is one seventh of the whole height of the frieze, and the projection of the cymatium is the same as its height.
Let the height of a rail be one third of the breadth of a panel, and its cymatium one sixth of the rail.
Its cymatium ought to be one sixth of the jamb, with a projection equivalent to its height.
The cymatium of the architrave should be one seventh of the height of the whole architrave, and its projection the same.
Let the corona and its cymatium at the top of all be carved without ornamentation, and have a projection equal to its height.
When the crowning moulding of an entablature is of the cyma form, it is called a “cymatium.”
It forms the crowning feature of the Egyptian temples, and took the place of the cymatium in many of the Etruscan temples.
Let the rest, excluding the cymatium, be divided into twelve parts.
Inwood remarks (p. 136) that the central enrichment over the cymatium between the volutes is unusual.