Using the Leyden jar, Franklin вЂњcollected electric fire very copiously,вЂќ Priestley recounted. He perceived a very evident electric spark,вЂќ Priestley wrote. вЂњStruck with this promising appearance, he immediately presented his knucle to the key, and (let the reader judge of the exquisite pleasure he must have felt at that moment) the discovery was complete. Just as he was beginning to despair, Priestley wrote, Franklin noticed loose threads of the hemp string standing erect, вЂњjust as if they had been suspended on a common conductor.вЂќДЇranklin moved his finger near the key, and as the negative charges in the metal piece were attracted to the positive charges in his hand, he felt a spark. Franklin attached it to the hemp string, and with his sonвЂ™s help, got the kite aloft. The last piece of the puzzle was the metal key. The silk string, kept dry as it was held by Franklin in the doorway of a shed, wouldnвЂ™t.

Why both? The hemp, wetted by the rain, would conduct an electrical charge quickly. To the bottom of the kite he attached a hemp string, and to that he attached a silk string. HereвЂ™s how the experiment worked: Franklin constructed a simple kite and attached a wire to the top of it to act as a lightning rod. Instead, the kite picked up the ambient electrical charge from the storm. If it had been, he probably would have been electrocuted, experts say. To dispel another myth, FranklinвЂ™s kite was not struck by lightning. FranklinвЂ™s experiment demonstrated the connection between lightning and electricity. Electrical forces had been recognized for more than a thousand years, and scientists had worked extensively with static electricity. Franklin, astonishing as it must have appeared, contrived actually to bring lightning from the heavens, by means of an electrical kite, which he raised when a storm of thunder was perceived to be coming on.вЂќДespite a common misconception, Benjamin Franklin did not discover electricity during this experiment-or at all, for that matter. вЂњTo demonstrate, in the completest manner possible, the sameness of the electric fluid with the matter of lightning, Dr.

So Franklin and his son вЂњtook the opportunity of the first approaching thunder storm to take a walk into a field,вЂќ Priestley wrote in his account. His son William assisted him.ДЇranklin had originally planned to conduct the experiment atop a Philadelphia church spire, according to his contemporary, British scientist Joseph Priestley (who, incidentally, is credited with discovering oxygen), but he changed his plans when he realized he could achieve the same goal by using a kite. He also had a house key, a Leyden jar (a device that could store an electrical charge for later use), and a sharp length of wire. He had his materials at the ready: a simple kite made with a large silk handkerchief, a hemp string, and a silk string.

He wanted to demonstrate the electrical nature of lightning, and to do so, he needed a thunderstorm. He decided it was the perfect time to go fly a kite.ДЇranklin had been waiting for an opportunity like this. As rain began to fall and lightning threatened, most of the cityвЂ™s citizens surely hurried inside. On a June afternoon in 1752, the sky began to darken over the city of Philadelphia. We all know the story of FranklinвЂ™s famous kite-in-a-thunderstorm experiment. WATCH: Ingenious: The Evolution of Innovation.Harry Potter: The Exhibition - FINAL WEEKS!.

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