Today in History: Ben Franklin Flies a Kite

On this day (June 15) in 1752, tradition has it that Benjamin Franklin proved that lightning is composed of electricity. Standing upon an insulator with a roof over his head to keep dry, Franklin flew a kite in a thunderstorm Apparently he did not wait for the kite to be struck by lightning, but used it to attract electrical charge which was demonstrated when sparks “stream out plentifully from the key [tied to the wet kite string] at the approach of your knuckle.”