A sickly child, a poor student, and a medical school dropout, Léon Foucault seemed an unlikely candidate for greatness. But his ingenious experiment—simple, beautiful, and stunningly original—changed how we see the world.

Scientists knew that the earth turned on its axis. But how could they prove it? Countless experiments had been tried . . . and had failed. Then, one historic day in Paris, Léon Foucault gave a magnificent demonstration that offered the proof everyone had been looking for.

Discover the improbable story of the man behind the famous Foucault's Pendulum.