Ben Franklin - Electricity and the Lightning Rod

Ben Franklin was a prolific inventor as well as an innovator. He had an inquisitive mind and he spent hours figuring out ways to make everyday living easier, as well as inventing new objects. He improved the wood burning stove so that it better heated homes, but also used less wood. Franklin had poor eyesight and invented the first bifocal eyeglasses to enable him to read better. He made paddles for his hands and feet in order to swim faster and farther, using less of his own energy.

Ben Franklin is credited with discovering natural electricity and inventing the lightning rod to capture and control the electrical current in lightning. Franklin had hypothesized that the driving force in lightning was electricity. In 1752, lightning was one of the major causes of fires in buildings and forests. Franklin began experimenting using kites that he controlled by string and flew during thunderstorms. After several attempts to get lightning to strike his kite, he realized he needed something to attract and conduct the lightning. He then attached a metal key to the kite and flew it into a thunderstorm. This was in June 1752. Lightning struck the key and sent an electrical current through the key and the kite. Franklin realized how his successful experiment could be used to prevent fires, caused by lightning. Next, he erected a metal rod on the roof of his house to capture the energy or electricity in the lightning. The nine foot rod was attached to his chimney and had two wires attached to it. The wires were covered by a glass tube. Wires and tube ran through his roof and into his home. He attached bells to the end of the two wires. When the lightning rod attracted a lightning strike, it captured the electricity in the lightning and funneled it down the wires to the bells, causing the bells to ring. Franklin's experiment was so revolutionary, he had to invent new words to describe the results. He had proven the existence of electricity and called it "electric fire." Also, that electricity traveled by flowing through conductors such as wires and water, making it "fluid". The metal rods became known as lightning rods. People began installing the lightning rods on their homes to attract lightning and funnel the electrical current down the rod and the wires that were attached to the rod. The wires were run across roofs and down to the ground, this was called "grounding." Next the wires were buried approximately ten feet underground. The electrical current ran into the ground and was extinguished rather than causing a fire on the roof of the structure.

Ben Franklin was a civic leader, a teacher, a writer and an inventor. He did not patent any of his inventions. He chose to share his knowledge with everyone freely.