Thomas Jefferson once wrote to a friend that politics was his "duty" but natural history was his "passion." As this book shows, he was always a man for whom nature was important. With Jefferson's devotion to detailed knowledge, precise calculation, and rational inquiry, natural history related to everything he did, as a farmer, as a philosopher, and as a citizen. For all his gifts in philosophy and politics and his fascination with the American West, Jefferson was never more happy than at home at Monticello, riding across the fields and experimenting with new crops. The great wonder is that in addition to his public life he had time to be one of America's first serious students of, among other things, fossils, botany, climate, geology, and anthropology.