Some of history's greatest recorded disasters involved the spewing magma or falling ash from an erupting volcano. This book takes readers deep under the earth to the source of a volcano's power and then around the world to some of the most spectacular eruptions in history. Volcano Alert! also includes: - the dangers of lava and pyroclastic surges - a look at the scientific tools volcanologists use to predict and measure eruptions - famous volcanoes such as Mount Etna, Mount Vesuvius, and Mount Pinatubo