Aaron Holz, assistant professor of art at the University of Nebraska-Lincoln, and Wendy Katz, an associate professor of art history, will speak about John Singleton Copley's Nicholas Boylston, one of the early masterpieces in American Art. The Sunday at Sheldon talk, titled "It Will Cost You an Arm and a Leg," will be in the Rohman Family Gallery, which has an installation of American portraiture.