As we grow older, there are certain images from childhood that we each remember. One of the images in my memory is the poster of American heroes that graced the wall of Miss Bosco’s first grade classroom. Denizens of the poster included Washington, Jefferson, Lewis and Clark and Lincoln. But the one I most remember was Benjamin Franklin flying his kite in an electric storm.
I loved the image but had no idea what Franklin was doing. Later, when I read about Franklin and his work with electricity, I thought the whole kite story was just one of those historical myths. But it isn’t. It actually happened—269 years ago on June 10th, to be exact.
Franklin’s fascination with electricity dates back to 1746 when he witnessed a series of experiments in Boston. He started conducting electrical experiments with friends in London, sometimes using his findings to play practical jokes on neighbors, like the burning alcohol trick, the charged wine glass that delivered a shock to the drinker or the candle that instantly relit after being blown out. But Franklin was serious about electricity. He invented a crude electric battery and theorized, correctly, that electricity could be either positive or negative.
On June 10, 1752, Franklin set out to draw lightning from the sky by placing a conductor close to the clouds from whence lightning seemed to originate. Franklin created a kite by draping silk over a cross consisting of two strips of cedar. To the string, he tied a key, and wrapped a silk ribbon around his hand as a crude insulation device.
It was a hot sultry day in Philadelphia and thunderstorms developed. Franklin flew his kite into the storm clouds and stood in a doorway to keep the silk around his hand dry. A bolt of lightning struck the kite and traveled down the twine to the key. Franklin took the charged key and touched a leyden jar, i.e., container for storing an electrical charge. Sure enough, once it was touched by the key, the jar became charged. Franklin had proven that lightning and electricity were one and the same.
The dangerous nature of Franklin’s experiment is enough to make any safety director cringe. But Franklin’s risky behavior can be forgiven especially when we consider how he continued his experiments to advance the cause of electrical safety by inventing the lightning rod, a device still used to protect homes and ships at sea from lightning.
Glenn Demby – Managing Editor – Bongarde