The alphabet of mouldings
Fillet, torus, astragal, scotia, ovolo, cavetto and the two cymas: the letters from which every classical profile is spelled.
The rules it illustrates
The alphabet of mouldings. Build every profile from a small set of elements (fillet, torus, astragal, scotia, ovolo, cavetto, cyma recta and cyma reversa), alternating curved with flat and light with shadow.
The Greek egg-and-dart. Space the eggs from centre to centre at the height of the moulding; make each egg as wide as the space between two eggs, and divide that space into three, giving the middle part to the dart and the outer parts to the shell that encloses each egg.
Where it appears in the book
In the chapters The Anatomy of an Order.
The terms it shows
Astragal · Cavetto · Cyma recta · Cyma reversa · Fillet · Moulding · Ovolo · Scotia · Torus