For weeks before the 1991 eruption of Mount Pinatubo in the Philippines, the volcano had been restless. The scientists in the area knew that the volcano might erupt, but they did not have the equipment or the manpower to monitor the volcano. They called on the United States for help, as writer Andrew Robinson explains: As soon as Pinatubo awoke in early April (after 600 years of quiet) the Philippine Institute of Volcanology and Seismology contacted friends at the U.S. Geological Survey. An American team was soon on its way with equipment not available in the Philippines: seismometers, tiltmeters and personal computers that used a new program capable of plotting, locating, and examining earthquakes around the volcano in real time-as the events unfolded: such analysis would previously have taken much longer. Filipino and US scientists could "follow easily and...