More than 130 years before Thomas Edison built the first incandescent electric light, Benjamin Franklin was experimenting with electricity.
Franklin hypothesized that lightning was caused by a discharge of electricity. He wrote his thoughts in several letters to a fellow scientist in London, leading to a 1751 book, “Experiments and Observations on Electricity.”
One of the letters contained Franklin’s plan to prove electricity and lightning were the same. His idea was to erect iron rods into storm clouds to attract electricity.
Franklin needed to get close enough to the clouds to attract the lightning. Unfortunately, Philadelphia had no hills or tall buildings. Franklin decided to wait while the tower and steeple at his house of worship, Christ Church, was built.
The church would have been a great place to test Franklin’s theory. When finished, Christ Church became the tallest building in the 13 Colonies, at 196 feet high.
But Franklin was impatient.
During a thunderstorm in Philadelphia in 1752—some say June 10, but most say it was June 15—Franklin infamously flew a kite. He reasoned that static electricity in the thundercloud would be attracted to wire pointing from the top of the kite and flow down the wet string to the ground.
Concerned that electricity would pass through and kill him if he held the end of the kite string directly, Franklin tied the string to a metal key and connected the key to a silk ribbon—an excellent electrical insulator—and stood under a rain shelter to stay dry.
Sure enough, static electricity moved down the wet string to the key but not through the ribbon. Franklin touched the key to an electrode protruding from the top of a glass jar, capturing the thundercloud’s electricity.
This led to Franklin’s invention of the lightning rod, which absorbs electrical current from lightning, protecting structures.
On June 15, take a moment to appreciate Franklin’s work.