What is a small channel, deeply recessed in proportion to its width, used to insulate and give relief to a convex rounded molding. Quirk molding, a bead between two quirks called?

quirk — (Arch.) A small channel, deeply recessed in proportion to its width, used to insulate and give relief to a convex rounded molding. Quirk molding, a bead between two quirks. (Webster's 1913.)

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