 In the early 19th century, French, English, and American trappers followed the trails that these indigenous people had made. Most returned. Stories they told of thundering waterfalls and cliffs made of glass, of mud volcanoes and geysers that exploded out of the ground, and huge clouds of steam and boiling water seemed absurd. Everyone knew that trappers were inveterate liars who loved a good story. It seemed foolhardy to believe them. And yet, what if these stories were true?