WASHINGTON - Hoping to learn more about undersea volcanoes, scientists sent a camera-equipped submarine down to take a look. They got more than they bargained for, witnessing a deep-sea eruption. "At first we really didn't understand what was going on," said Bob Embley, chief scientist on the mission, which involved nearly three dozen researchers. "We were seeing billowing clouds coming up and turning yellow. There was sulfur and rocks were flying out," said Embley, an oceanographer with the National Oceanic and Atmospheric Administration's Pacific Marine Environmental Laboratory. "We realized we were the first to witness a deep-sea volcano during...