When Mount Vesuvius blew up in A.D. 79, ash, cinders, and stones buried a great city below the mountain. Volcanoes are dramatic and powerful. There are thousands of them all over the earth. Franklyn M. Branley's clear text and Megan Lloyd's striking illustrations explore the fascinating subject of volcanoes—how they form and erupt, where they are found, and when you can expect a volcano to blow its top.