On Juneteenth, Tiya Miles, professor of history and former chair of the Charles Warren Center for Studies in American History at Harvard University and the National Book Award–winning author of All That She Carried, talks about her new book, Night Flyer: Harriet Tubman and the Faith Dreams of a Free People (Penguin Press, 2024), that places Harriet Tubman in the context of the natural world she inhabited and her spirituality.