The west wing of the home was added in 1887 to house Mr. Moore's vast collection of books. At the time of his death, he owned approximately 7,000 volumes, the largest collection of books in downstate Illinois. The two-story high library has a vaulted ceiling and stenciled walls. There are four-season windows on the upper level, and an iron railing around the suspended upper gallery. The furniture and paintings include many of the original Moore furnishings. Moore's book collection was left to the city of Clinton upon his death and is now housed at the Vespasian Warner Public Library.