Mr. Nussbaum - Ben Franklin Discovers Electricity

This is an historical account of Franklin's famous kite experiment.

Franklin Discovers Electricity

Benjamin Franklin Discovers Electricity

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Benjamin Franklin was one of most innovative Americans of all time. In deed, his work and experiments resulted in several important discoveries and inventions including electricity, bifocal glasses, a usable battery and many more.

Preparing for Discovery

Ben Franklin believed electricity could be harnessed from lightning. In 1752, he devised an experiment to test his theory. Although details of the experiment remain sketchy to this day, Franklin originally wanted to test his theory atop a spire that was to be built on a Philadelphia church. As he thought about it in detail, he realized that his theory could be better tested by using a mobile kite, rather than a stationary spire. Franklin prepared the kite by tying a handkerchief to two crossed sticks of proper length. Extending vertically about a foot from the vertical stick was a wire. The apparatus was extended into the air by a length of string. Along the string of the apparatus was a metal key that would apparently conduct the electricity. Franklin hypothesized that the wire would draw 'electric fire' from the thunder clouds which would then be conducted through the apparatus and be contained in the key.

He was right!

Franklin used his apparatus to test the idea in a Philadelphia field equipped with a shed. Franklin kept his experiment a secret because he feared he would be ridiculed. He only told his 21 year-old son who had assisted him in the kite's construction. He stood in the field with the kite in the sky for some time. As menacing clouds passed over head with no luck, Franklin became discouraged and was about to go home. Suddenly, he observed some threads of the kite string stand erect. Believing the cause to be an electrical current, Franklin extended his knuckle to the key and was shocked (not seriously). Soon after, others witnessed the experiment and it was proven (The French had actually conducted similar experiments a month before).

Effects of Franklin's Experiment

Based on this landmark experiment, Franklin invented the first lightning rod. The lightning rod was built to attract electricity to his house. The lightning rods were attached to a system of bells that would ring throughout his house each time electricity had been attracted. The sparks produced would illuminate the house. Franklin's experiments helped the evolution of the common battery we use today.