When a man called the Smithsonian's National Museum of American History and claimed that his great-great grandfather had written a secret message in Lincoln's watch, curator Harry Rubenstein was intrigued. Listen as Harry explains the steps he took to verify this family folklore. This video series, "Explore with Smithsonian Experts," connects students and teachers with the skill and technique of Smithsonian experts who describe their work at our nation's museums. In each short film, experts introduce new ways to observe, record, research, and share, while using real artifacts and work experiences. Supports Common Core ELA standards. Produced by the Smithsonian Center for Learning and Digital Access and Pearson Foundation.