The 1883 volcanic explosion of Krakatoa in Indonesia could be heard 3000 miles away. It killed tens of thousands of people and lowered temperatures worldwide, yet it has been little explored until now. Larry Mantle talks with bestselling author Simon Winchester about his fascinating new book called Krakatoa: The Day the World Exploded (Harper Collins), which the New York Times has called "one of the best books written about the history and significance of a natural disaster."