NOTE: This is the first of a series of short essays for the Classicist Blog by Calder Loth on various aspects of Classical architecture.
The block modillion is a little used classical detail but one meriting greater attention. Hardly any architectural treatises or glossaries make note of it. In fact, it is difficult to find agreement on what to call it.[i] Among the few 18th century architectural design books to illustrate the block modillion is James Gibbs’s Rules for Drawing the Several Parts of Architecture (1732). For plates LX and LXI, Gibbs describes cornices employing block modillions as “block cornices”. The most conspicuous ancient use of the block modillion is seen in the cornices of the main body of the Pantheon in Rome (figs. 1 & 2). Block modillions also survive on the Curia Julia (A.D. 283) in the Roman Forum, but this building was not illustrated in any of the Renaissance or 18th-century treatises. Detailed drawings of the Pantheon’s block modillions were first published in Palladio’s Quattro Libri (1570). A more precise illustration appeared in Antoine Desgodetz’s 1682 Les Edifices Antiques de Rome (fig. 3). Here we see the modillion essentially as a square block reduced by nearly half by undercutting with a cyma recta curve, replicating the profile of a standard crown molding. Rome’s Coliseum has block modillions in its uppermost cornice; however, they employ a cyma reversa profile (fig. 4).
For colonial America, Palladio’s and Gibbs’s illustrations of the block modillion probably served as the main sources for the form. One of America’s earliest uses of the block modillion is the exterior cornice of the 1748 Public Records office in Williamsburg, Virginia (figs. 5 & 6). William Buckland showed that block modillions were suitable for interiors, even in an exotic setting, when he applied them in the cornice of the Chinese Room at Gunston Hall, completed in 1755 (figs.7 & 8). George Washington also used block modillions for Mount Vernon’s stair hall cornice, but switched to cyma reversa block modillions for the exterior cornice (fig. 9). A source for Washington’s builders may have been Plate XLIII in Batty Langley’s Builder’s and Workman’s Treasury of Designs (1740), a work that includes the design for Mount Vernon’s rusticated pediment window.[ii] We find a 20th-century example on Richmond’s Monument Avenue where block modillions make a bold cornice for a 1929 three-story town house (figs. 10 & 11). The block modillion cornice, either wood or masonry, can be a distinctive character-defining feature for restrained classical works of the 21st- century.
Calder Loth is the Senior Architectural Historian for the Virginia Department of Historic Resources and a member of the Institute’s Advisory Council.
He was the 2010 recipient of ICA&CA’s 2010 Arthur Ross Awards, Board of Directors Honor.