Stroke of Good Fortune: A wealth of data from petrified lightning Sid Perkins The lumps of glass created when lightning strikes sandy ground can preserve information about ancient climate, new research indicates. BOLT FROM THE BLUE. When lightning strikes the ground, it fuses sand in the soil into tubular masses of glass called fulgurites (top). The gases trapped in bubbles in that glass (bottom) yield clues to ancient soil and atmospheric chemistry and climate. L. Carion/Carion Minerals, Paris; Navarro-González Worldwide, lightning flashes occur about 65 times per second. Each bolt releases as much energy as is stored in a quarter-ton...
