“We made several experiments on fowls this winter,” Benjamin Franklin wrote in February 1750. The experiments involved electricity, a phenomenon Franklin was investigating after his retirement from the Pennsylvania Gazette. Franklin had rigged a Leyden jar, which stored electrical charge, to wires to see if the current could kill chickens and turkeys—more humanely than by hatchet, as was commonplace. It worked on the chickens. “But the turkeys, though thrown into violent convulsions, and then lying as dead for some minutes, would recover in less than a quarter of an hour.”
Franklin persisted, linking several electrical jars together. “We killed a turkey with them of about 10 lb. wt. and suppose they would have killed a much larger,” he reported. He added, “The birds killed in this manner eat uncommonly tender.”
The reason Franklin thought he might have killed a much larger turkey with his electrocution apparatus was that he nearly killed himself. He treated the mishap as a learning experience. “I found that a man can without great detriment bear a much greater electrical shock than I imagined,” he said. “For I inadvertently took the stroke of two of those jars through my arms and body, when they were very near full charged. It seemed an universal blow from head to foot throughout the body, and was followed by a violent quick trembling in the trunk, which gradually wore off in a few seconds. It was some moments before I could collect my thoughts so as to know what was the matter.”
Far from being put off by his brush with death, Franklin was thrilled with the knowledge gained. And he applied this knowledge to a longstanding puzzle, regarding the nature of lightning. Its jagged bolts reminded him and others of the sparks they made in their laboratories; they wondered if there was a connection.
Franklin decided to find out. “To determine the question whether the clouds that contain lightning are electrified or not, I would propose an experiment to be tried where it might be done conveniently,” he wrote. “On the top of some high tower or steeple, place a kind of sentry box big enough to contain a man and an electrical stand”—an insulated platform. “From the middle of the stand let an iron rod rise, and pass bending out of the door, and then upright 20 or 30 feet, pointed very sharp at the end. If the electrical stand be kept clean and dry, a man standing on it when such clouds are passing low might be electrified and afford sparks, the rod drawing fire to him from the cloud.”
Franklin’s proposed experiment made him famous. He already possessed a reputation among electricians—the term for scientists in this new field—in England, but when one of those electricians published Franklin’s design and other of his findings and reflections on electricity, his reputation leaped the English Channel to France and the rest of the European continent. King Louis urged his best men in Paris to put Franklin’s plan to the test; when they did and achieved the predicted results—the sparks drawn from the heavens, as it were—Franklin became a household word among scientists throughout the Western world.
Franklin himself didn’t try the experiment until a bit later. He had been waiting for the construction of a tall enough tower or steeple, but then conceived an alternate route to the heart of the storm. In June 1752 he flew a kite in a field outside Philadelphia; the kite carried a sharp wire in lieu of the pointed rod. Hemp twine, which conducted electricity, especially when wet, would carry any charge down to him on the ground. A key served as the collector of charge; Franklin would test the key with his knuckle.
No charge appeared at first. The news of the experiments in France hadn’t reached America, and Franklin feared there was a flaw in his design. Joseph Priestley, a distinguished scientist in his own right, and one to whom Franklin recounted the events of that day, related them to posterity: “At length, just as he was beginning to despair of his contrivance, he observed some loose threads of the hempen string to stand erect, and to avoid one another, just as if they had been suspended on a common conductor. Struck with this promising appearance, he immediately presented his knuckle to the key, and (let the reader judge of the exquisite pleasure he must have felt at that moment) the discovery was complete. He perceived a very evident electric spark. Others succeeded, even before the string was wet, so as to put the matter past all dispute, and when the rain had wet the string, he collected electric fire very copiously.”
Franklin’s achievement earned him renown enjoyed by no one else in the American colonies. He won the Copley Medal, the highest award in British science; the philosophes of the French Enlightenment swooned over the untutored genius of the New World.
Franklin appreciated the recognition, but his country—that is, the United States, when it declared independence—was the greater beneficiary. Had there been no American Revolution, the world most likely never would have heard of Washington, Adams, Jefferson, Hamilton and the other founders, who would have remained provincials in a far corner of the British empire. But the world already had heard of Franklin, the only pre-Revolution celebrity of the bunch.
He exploited that celebrity when, as America’s chief diplomat, he traveled to Paris seeking an alliance with France. King Louis was skeptical, being occupationally opposed to anti-monarchical revolutions, but the rest of Paris loved and feted Franklin. His popularity brought financial and moral support from the bourgeoisie that kept the American war effort afloat until the battlefield tide turned in America’s favor and Louis was finally persuaded. After the war, Franklin negotiated the peace treaty with Britain that confirmed American independence and gave the new country generous borders.
One of Franklin’s French admirers, the economist and statesman Turgot, summarized Franklin’s importance for humanity: “He snatched the lightning from heaven, and the scepter from tyrants.”
But still, don’t try it at home.