An architect friend reminded me of an extraordinary octagonal house in Natchez, Mississippi. Longwood was built just before the Civil War for Dr. Haller Nutt, a cotton planter, by the Philadelphia architect, Samuel Sloan. Construction was interrupted by the war (the Philadelphia craftsmen simply went home), and after Nutt’s death in 1864 construction stopped altogether. Although the brick shell and verandas were completed, only the basement was ever finished inside. Sloan’s plan is remarkable, since by the judicious placement of the verandas he manages to create two ranges of rooms (there were to be 32 rooms in all). The central space is top lit by the onion-domed cupola, making this a distant cousin of Palladio’s Villa Rotonda, although the architecture is not classical but Byzantine-Moorish—or something.