Do you think of volcanoes as simply big mountains with lava streaming over their tops? Not all of them are like that. Some are covered in ice, and some look like nothing more than deep blue lakes. Some have not erupted in living memory and still may awaken someday to send red-hot rocks and ash flying through the air for hundreds of miles around. Acclaimed science writer Seymour Simon and the Smithsonian Institution have come together to update this smartly written and beautifully photographed treatment of one of nature's hottest topics.