User Clip: Thomas Allen - Invisible Ink Part 1

Mr. Allen talked about his book, George Washington, Spymaster: How the Americans Outspied the British and Won the Revolutionary War, published by National Geographic. In the book, the author examines some of the covert techniques used by General George Washington to get messages to American commanders in the Revolutionary War. During the presentation, Mr. Allen demonstrated how invisible ink can be created using lemon juice. He also discussed various codes used by Washington. Following prepared remarks, Mr. Allen responded to questions from the audience. close