When thus enriched the moulding is formed as to its profile, and the details carved back from the face, leaving the highest parts in the original surface. The carving being deeper and more sharply defined in the case of mouldings that are in shadow. Such, for example, as the Ovolo, and in lighter relief on those more exposed to direct light.
The decoration of mouldings ordinarily consists of the repetition of a unit, composed on a central axis, in which curves are contrasted with vertical features.
No. 135.
The principle involved is to base the detail on the sectional curvature or profile line.
Orthodox Details
Thus the orthodox detail of the Ovolo, technically known as the “Egg and Tongue,” consists of a framing curve, which is obtained by repeating the profile on a centre line enclosing an ovoid shape. The angles between the outer curves being occupied by a tongue or dart.
As previously stated, this moulding is deeply carved, the ovoid being bold and well-rounded; the edges of the framing curves (in some instances grooved or channelled) being left sharp and precise.