Longwood in Natchez, Mississippi, is a celebration of American eccentricity. Dr. Haller Nutt, who made a fortune in cotton during the pre-Civil War boom, wanted a home that would be different, one with "character." His dream was romantic--to evoke past cultures by using the best from any era. A Philadelphia architect, Samuel Sloan, published a work in 1851 called The Model Architect which featured an "Oriental Villa" in octagonal form...