Lightning

—A discharge of atmospheric electricity, exhibited in flashes of various types taking place between the clouds and the earth, or between neighboring clouds. There are many forms of lightning, such as ball, chain, forked, globular, zigzag, ete. It has been estimated that the pre ure required for a lightning flash a mile long would be over three and one half million volts. Zigzag lightning resembles the spark from an electric machine. a disruptive discharge should pa through a living animal it is often fatal. As a discharge reaches the earth, the heat is sufficient, sometimes, to fuse sand.