Introduction
Benjamin Franklin is one of the most famous and admired founding fathers of the United States. He was a polymath who excelled in many fields, including science, politics, writing, inventing, diplomacy and more. However, what is less known is Franklin's pioneering work in electricity and electrical science. His discoveries and experiments laid the groundwork for many later advances in the field. In this article, I will explore Franklin's early electrical experiments in depth, to uncover the secret genius and radical thinking behind them.
Franklin's Early Fascination with Electricity
From a young age, Benjamin Franklin was fascinated by electricity and sought to understand its mysteries. In 1746, when Franklin was 40 years old, electricity was still a relatively new and unexplored phenomenon in science. Most saw it as a curiosity, producing sparks and shocks, but Franklin recognized its great potential.
He began conducting his own electrical experiments using simple materials he found around his household. He used things like glass tubes, cork balls, lead sheets and wires to test different electrical principles. Franklin was driven by his endless scientific curiosity. In one of his many letters, he wrote:
"My thoughts were turned to electricity and I never was before engaged in any study that so totally engrossed my attention and my time as this has lately done."
Franklin's Kite Experiment
One of Franklin's most famous electrical experiments was his legendary kite experiment in 1752. He wanted to demonstrate that lightning was in fact electricity. This was highly controversial and countered the prevailing scientific opinion that lightning was caused by "vitreous" and "sulphurous" emissions.
Franklin hypothesized that electricity could be drawn down from storm clouds through metal. So he flew a kite with a metal key attached during a thunderstorm. Using a Leyden jar, he was able to capture the electrical charge from the key, proving his theory correct. This dangerous experiment demonstrated Franklin's fearlessness in the pursuit of scientific knowledge. The kite experiment cemented his reputation and paved the way for the lightning rod.
Investigating Positive and Negative Charges
A key electrical phenomenon that fascinated Franklin was the existence of opposite positive and negative charges. He coined the positive and negative terminology we still use today. Franklin investigated how like charges repel each other while opposite charges attract.
Through his experiments, he realized that electrical charge is never created or destroyed, only transferred from one object to another. This crucial principle of charge conservation became fundamental to the study of electromagnetism. Franklin's insights were decades ahead of his time.
The Leyden Jar - A Primitive Capacitor
One of Franklin's more ingenious early inventions was his improved version of the Leyden jar, which was an early form of capacitor. It could store a substantial electrical charge between metal foil on the inside and outside of a glass jar. The jar's contents served as the dielectric material.
Franklin figured out how to increase the Leyden jar's capacitance and pioneered ways to connect multiple jars in parallel and series to increase power. This allowed him to deliver much stronger electrical shocks for experiments. The Leyden jar was a crucial piece of equipment in laboratories at the time. Franklin's improvements advanced electrical research.
Franklin's Radical Electrical Ideas
Benjamin Franklin developed many radical theories about electricity that went against orthodox scientific views. He proposed that electrical phenomena in nature like lightning, the aurora borealis and more were caused by a single electrical fluid that could have excess or deficiency.
This was opposed by the two-fluid theory which posited separate vitreous and resinous fluids. Franklin's pioneering one-fluid theory was eventually proven right. Also, he believed electricity could flow between objects without contact, anticipating electrostatic induction and other long-range effects. His electrical thinking was extremely innovative.
Lasting Influence on Science
Franklin's numerous discoveries and contributions firmly established electricity as a significant new field of scientific inquiry. He retired from active electrical experiments in 1753 to focus on diplomacy and politics. But he remained deeply interested in science for the rest of his life.
Benjamin Franklin's early electrical experiments displayed his fearless curiosity, technological ingenuity and radical thinking that were decades ahead of his contemporaries. The field-defining insights from his pioneering work Electrification of the Experiments helped shape modern electromagnetism and electrical engineering. He remains one of the greatest scientific minds America has ever produced.