Benjamin Franklin and the Kite Experiment
We all know the story of Franklin’s famous kite-in-a-thunderstorm experiment. But is it the true story?
On a June afternoon in 1752, the sky began to darken over the city of Philadelphia. As rain began to fall and lightning threatened, most of the city’s citizens surely hurried inside. But not Benjamin Franklin. He decided it was the perfect time to go fly a kite.
Franklin had been waiting for an opportunity like this. He wanted to demonstrate the electrical nature of lightning, and to do so, he needed a thunderstorm.
He had his materials at the ready: a simple kite made with a large silk handkerchief, a hemp string, and a silk string. 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. His son William assisted him.
Franklin 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.
So Franklin and his son “took the opportunity of the first approaching thunder storm to take a walk into a field,” Priestley wrote in his account. “To demonstrate, in the completest manner possible, the sameness of the electric fluid with the matter of lightning, Dr. 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.”
Despite a common misconception, Benjamin Franklin did not discover electricity during this experiment—or at all, for that matter. Electrical forces had been recognized for more than a thousand years, and scientists had worked extensively with static electricity. Franklin’s experiment demonstrated the connection between lightning and electricity.
The Experiment To dispel another myth, Franklin’s kite was not struck by lightning. If it had been, he probably would have been electrocuted, experts say. Instead, the kite picked up the ambient electrical charge from the storm.
Here’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. To the bottom of the kite he attached a hemp string, and to that he attached a silk string. Why both? The hemp, wetted by the rain, would conduct an electrical charge quickly. The silk string, kept dry as it was held by Franklin in the doorway of a shed, wouldn’t.
The last piece of the puzzle was the metal key. Franklin attached it to the hemp string, and with his son’s help, got the kite aloft. Then they waited. Just as he was beginning to despair, Priestley wrote, Franklin noticed loose threads of the hemp string standing erect, “just as if they had been suspended on a common conductor.”
Franklin 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.
“Struck with this promising appearance, he immediately presented his knucle [sic] 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,” Priestley wrote.
Using the Leyden jar, Franklin “collected electric fire very copiously,” Priestley recounted. That “electric fire”—or electricity—could then be discharged at a later time.
Franklin’s own description of the event appeared in the Pennsylvania Gazette on October 19, 1752. In it he gave instructions for re-creating the experiment, finishing with:
As soon as any of the Thunder Clouds come over the Kite, the pointed Wire will draw the Electric Fire from them, and the Kite, with all the Twine, will be electrified, and the loose Filaments of the Twine will stand out every Way, and be attracted by an approaching Finger. And when the Rain has wet the Kite and Twine, so that it can conduct the Electric Fire freely, you will find it stream out plentifully from the Key on the Approach of your Knuckle. At this Key the Phial may be charg’d; and from Electric Fire thus obtain’d, Spirits may be kindled, and all the other Electric Experiments be perform’d, which are usually done by the Help of a rubbed Glass Globe or Tube; and thereby the Sameness of the Electric Matter with that of Lightning compleatly demonstrated.
Franklin wasn’t the first to demonstrate the electrical nature of lightning. A month earlier it was successfully done by Thomas-François Dalibard in northern France. And a year after Franklin’s kite experiment, Baltic physicist Georg Wilhelm Richmann attempted a similar trial but was killed when he was struck by ball lightning (a rare weather phenomenon).
After his successful demonstration, Franklin continued his work with electricity, going on to perfect his lightning rod invention. In 1753, he received the prestigious Copley Medal from the Royal Society, in recognition of his “curious experiments and observations on electricity.”
By Nancy Gupton. Published June 12, 2017.
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When Benjamin Franklin Shocked Himself While Attempting to Electrocute a Turkey
The statesman was embarrassed by the mishap—no doubt a murder most fowl
Timothy J. Jorgensen
Most everyone knows that Benjamin Franklin was not only a famous statesman but also a great inventor and scientist , particularly in the field of electricity. He actually introduced much of the electrical terminology still in use today, including battery, conductor, positive charge, negative charge, current and discharge.
Among his many electrical experiments, the one for which Franklin is most celebrated is his successful attempt to capture the electricity of thunderclouds in a jar. But this victory might never have happened if not for a painful lesson he’d learned from one of his lesser-known tests, an experiment performed two years earlier, in December 1750. During that failed endeavor , Franklin was traumatized and humbled by an unexpected foe: a turkey.
Spark: The Life of Electricity and the Electricity of Life
A fresh look at electricity and its powerful role in life on Earth
Franklin’s strategy for the June 1752 experiment —inspired, perhaps, by that avian accident—was to fly a kite with a wire pointing up from its top near a passing thundercloud. He reasoned that static electricity in the cloud would be attracted to the wire and flow down the wet kite string on its way to the ground. But he was concerned that if he were to hold the end of the kite string directly, he might very well be killed as the electricity passed through him. So, he decided to take precautions by tying the end of the kite string to a metal key and connecting the key to a silk ribbon. He would control the kite by holding the silk ribbon rather than the string.
Because dry silk is an excellent electrical insulator, Franklin felt it would provide him the needed protection against the electricity. To ensure the silk ribbon remained dry, he flew the kite while standing in a small rain shelter. Sure enough, when the kite was in the sky, static electricity moved down the wet string as far as the key—but not through the silk ribbon to his body. Franklin then touched the metal key to an electrode protruding from the top of a Leyden jar (an electricity-storing glass jar recently invented by Dutch physicist Pieter van Musschenbroek). He’d captured the thundercloud’s electricity in a glass jar, making history in the process. And, just as importantly, he’d live to tell about it.
Given the magnitude of electricity that Franklin was handling, his precautions may seem insufficient to modern observers; nevertheless, he did consider the dangers and had planned accordingly to protect his life. Precisely because he survived, his kite experiment is now world famous .
The reason why Franklin took such detailed precautions may very well have been due to his earlier encounter with a turkey. Besides electricity, Franklin had a vested interest in the birds. Popular lore suggests he wanted the wild turkey rather than the bald eagle—both animals native to North America—to be named the national bird of the United States. But the Franklin Institute , a Philadelphia-based science museum and education center that bears the politician’s name, deems this story a myth. In truth, the organization writes on its website, Franklin simply criticized the Great Seal’s original eagle design for too closely resembling a turkey, which he called “a much more respectable Bird, ... a little vain & silly, [but] a Bird of Courage.”
Franklin’s love of turkeys stemmed primarily from his gastronomic interests . He was very fond of food, and turkey was one of his favorite dishes. For some reason, he believed a turkey killed with electricity would be tastier than one dispatched by conventional means: decapitation. As fellow scientist William Watson wrote in 1751, Franklin claimed that “birds kill’d in this manner eat uncommonly tender.”
The statesman set out to develop a standard procedure for preparing turkeys with static electricity collected in Leyden jars. One day, while performing a demonstration of the proper way to electrocute a turkey, he mistakenly touched the electrified wire intended for the turkey while his other hand was grounded , thereby diverting the full brunt of the turkey-killing charge into his own body. Writing to his brother John two days later, on Christmas Day in 1750, Franklin detailed what happened next:
The company present ... say that the flash was very great and the crack as loud as a pistol; yet my senses being instantly gone, I neither saw the one nor heard the other; nor did I feel the stroke on my hand, though I afterward found [that] it raised a round swelling where the fire entered as big as half a pistol bullet, by which you may judge of the quickness of the electrical fire, which by this instance seems to be greater than the sound, light or animal sensation.
Acknowledging the oversight that led to this shock (“I might safely enough had done if I had not held the chain in the other hand,” he wrote), Franklin attempted to describe the intense pain he’d experienced:
I then felt what I know not how well to describe—a universal blow through my whole body from head to foot, which seemed within as well as without; after which the first thing I took notice of was a violent, quick shaking of my body, which, gradually remitting, my sense as gradually returned, and I then thought the bottles must be discharged, but could not conceive how, till at last I perceived the chain in my hand, and recollected what I had been about to do. That part of my hand and fingers which held the chain was left white, as though the blood had been driven out, and remained so eight or ten minutes after, feeling like dead flesh; and I had a numbness in my arms and the back of my neck, which continued till the next morning, but wore off. Nothing remains now of this shock but a soreness in my breast bone, which feels as if I had been bruised. I did not fall but suppose I should have been knocked down if I had received the stroke in my head. The whole was over in less than a minute.
Franklin appears to have been very embarrassed by his foolish behavior with the turkey. In the letter to his brother, he ended by saying, “You may communicate this to Mr. Bowdoin [a friend who was also experimenting with electricity] as a caution to him, but do not make it more public, for I am ashamed to have been guilty of so notorious a blunder.”
It’s probably safe to say that all the turkey-eating enthusiasts who witnessed Franklin’s accident that day decided decapitation was still the best way to prepare turkeys for the table. After all, the kite experiment never would have happened if Franklin’s turkey experiment had killed him first.
Adapted from Spark: The Life of Electricity and the Electricity of Life by Timothy J. Jorgensen. Copyright © 2021 by Timothy J. Jorgensen. Reprinted by permission of Princeton University Press.
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Timothy J. Jorgensen | READ MORE
Timothy J. Jorgensen is a professor at the Georgetown University School of Medicine. He is author of the award-winning book Strange Glow: The Story of Radiation (Princeton, 2016), and the newly published Spark: The Life of Electricity and the Electricity of Life (Princeton, 2021). He lives in Rockville, MD.
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Experiments with electricity
Diagrams of various electrical phenomena in Experiments and Observations on Electricity. Library of Congress
Benjamin Franklin left an important legacy in electrical science and its useful application to mankind. The experiments published in “ Experiments and Observations on Electricity Made at Philadelphia in America” proved the existence of positive and negative charges as well as the concepts of insulators and conductors. His work led to the invention of the lightning rod which saved buildings from being struck by lightning.
The first time the word “electricity” was printed was in 1646 by Thomas Browne in Pseudodoxia Epidemica. In it he describes static electricity produced by rubbing two objects. Further studies were conducted by Boyle, Gilbert, Gray, von Guericke and du Fay in magnetism and electricity. The invention of the Leyden jar in 1745 was a most significant advance.
The Leyden Jar
The Leyden Jar was named after the city where it was invented, Leiden (Leyden), Netherlands.
In 1746, while visiting his family in Boston, Benjamin Franklin met Dr. Spence who had arrived from Scotland. He showed Franklin electric experiments with the Leyden Jar which caught his attention and curiosity. When Franklin returned to Philadelphia the Junto Club had received a glass tube sent by Peter Collison from the Royal Society of London . After much experimenting he wrote several letters to Collison about his findings and success using it.
One of his first experiments was to give electrical shocks in the limbs of paralyzed individuals. He placed Leyden jars in their limbs sending electric shocks. Though initially beneficial, most people relapsed after several days. In his autobiography he wrote after his experiments with patients that he: “never knew of any advantage from electricity in palsies that was permanent”. Today doctors use electric impulses to stimulate muscles and prevent atrophy.
Another experiment and perhaps his most famous was drawing electricity from clouds and storing it in the Leyden Jar.
Royal Society of London
One of the letters Franklin sent to Peter Collison was on the Sameness of Lightning with Electricity in which he hypothesized that lightning was an electrical discharge. His letter was read to the Royal Society of London. Connoisseurs of the society laughed and ridiculed his findings and thought it was not worth being printed in their Philosophical Transactions. However, a member of that society, Dr. Fothergill considered his ideas of too much value and advised Collison that the paper was worth publishing. Collison gave the papers to Cave for publication in his Gentleman’s Magazine. It was printed separately from the magazine in a pamphlet with the preface written by Dr. Fothergill.
Kite Experiment
The kite experiment uncovered unknown facts about lighting and electricity.
Before Franklin had the chance to conduct his own experiment, two scientists in France, Dalibard and Delor, had tested his hypothesis proving his theories correct. They reported to the King of France that the extraordinary American has shown that you can draw electricity from lightning. Franklin was about to become the most famous American in the world.
Consecutive letters were published and were assembled into a book “Experiments and Observations on Electricity Made at Philadelphia in America” with the permission of Franklin. The presentation of his experiments was in the form of correspondence which gives minute details of his experiments.
What gave this book its instant celebrity was one of its experiments, drawing electricity from clouds. Benjamin Franklin was later made member of the Royal Academy of London and presented with the Gold Medal of Sir Godfrey Copley in 1753.
Franklin’s letters about his experiments with electricity
These are Franklin’s letters about his electricity experiments written to Peter Collison, Cadwadaller Colden and Jared Eliot in a span of seven years. These and other letters were compiled into “Experiments and Observations on Electricity Made at Philadelphia in America”
» Letter from Benjamin Franklin to Peter Collison dated March 28, 1747
» Letter from Benjamin Franklin to Peter Collison dated May 25, 1747
» Letter from Benjamin Franklin to Peter Collison dated July 28, 1747
» Letter from Benjamin Franklin to Peter Collison dated April 29, 1749
» Letter from Benjamin Franklin to John Mitchel dated April 29, 1749
» Letter from Benjamin Franklin to Peter Collison dated July 29, 1750
» Letter 2 from Benjamin Franklin to Peter Collison dated July 29, 1750
» Letter from Benjamin Franklin to Peter Collison dated September 27, 1750
» Letter from Benjamin Franklin to Peter Collison dated June 29, 1751
» Letter from Benjamin Franklin to Cadwallader Colden dated October 31, 1751
» Letter from Benjamin Franklin to Peter Collison dated October 19, 1752
» Letter from Benjamin Franklin to Cadwallader Colden dated April 12, 1753
» Letter from Benjamin Franklin to Jared Eliot dated April 12, 1753
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Scientific observations and discoveries.
Benjamin Franklin & Static Electricity
Published May 17, 2018
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Understanding the basics of what electricity is can really help anybody learning about electronics, circuit design, power engineering, and so on. So, let’s start with a little history of electricity with a story about Benjamin Franklin and how he discovered static electricity. Not his kite, even though that is a much more popular story and has had many animated reenactments on YouTube. I’m going to talk about his strange obsession with rubbing glass and hard rubber with silk and fur.
Ben would rub a glass rod with silk and another rubber rod with fur while hanging those rods from string. To more easily emulate this experiment today, we can use a plastic rod and wool instead of rubber and fur. If he rubbed two glass rods with silk and brought them close together or two rubber rods with fur and did the same, they would repel each other. But if he rubbed a glass rod with silk and a rubber rod with fur, those two would attract.
He didn’t realize what he was doing, but he was actually removing electrons from the glass rod when he used silk and adding electrons to the rubber when he used fur. Though he didn’t know what was going on exactly, he figured out that there was a positive charge and a negative charge and like, or similar charges, repel each other, while opposite charges attract each other. He decided that the glass rod being rubbed with silk would be a positive charge while the rubber and fur would be a negative charge. So, with that convention, by removing electrons, the glass rod became positively charged and by adding electrons, the rubber rod became negatively charged.
All atoms are made up of a nucleus made up of protons and neutrons with electrons flying around them. For Franklin’s experiments, the rubbing motion was physically removing the electrons from the atoms making up the glass rod or physically adding electrons to the rubber rod. Now, one view of electricity is that it is the flow of electrons but since the electrical charge on these objects doesn’t go anywhere, it is considered static electricity. Though some may disagree, this is a bit of a misnomer as the electrons do move when the object comes in physical contact with something else at a different charge and everything equalizes, usually in the form of a painful zap or nocturnal light show.
In summary:
- Positive and negative charges
- How Benjamin Franklin discovered charges
- Electricity (14)
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Josh bishop.
Interested in embedded systems, hiking, cooking, and reading, Josh got his bachelor's degree in Electrical Engineering from Boise State University. After a few years as a CEC Officer (Seabee) in the US Navy, Josh separated and eventually started working on CircuitBread with a bunch of awesome people. Josh currently lives in southern Idaho with his wife and four kids.
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Benjamin Franklin’s Kite Experiment: What Do We Know?
By: Becky Little
Updated: June 14, 2023 | Original: June 6, 2022
On June 10, 1752, Benjamin Franklin took a kite out during a storm to see if a key attached to the string would draw an electrical charge. Or so the story goes. In fact, historians aren’t quite sure about the date of Franklin’s famous experiment, and some have questioned whether it took place at all.
Even if Franklin’s kite and key experiment did happen, it didn’t play out the way many people think it did. Contrary to popular myths, Franklin didn’t conduct the experiment to prove the existence of electricity. In addition, it’s very unlikely that lightning struck a key while Franklin was flying a kite—because if it had, Franklin probably would have died.
Franklin Didn't Write Much About the Experiment
Everything we know about Franklin’s kite and key experiment comes from two sources . The first is a letter Franklin wrote to his friend Peter Collinson in October 1752 that was published in the The Pennsylvania Gazette and read before the Royal Society. The second is a section of Joseph Priestley’s 1767 book History and Present Status of Electricity , in which Priestley recounted what Franklin had presumably told him about the experiment.
In the letter, Franklin wrote that an “Experiment has succeeded in Philadelphia” using a kite and key, and detailed how one could go about reproducing the experiment. He didn’t specify when the experiment took place or whether he had actually conducted it. Fifteen years later, Priestley provided some more details, writing that 46-year-old Franklin and his 22-year-old son William had conducted the experiment sometime in June 1752.
Scholars of Franklin have speculated that the experiment occurred around June 10, though no one really knows what date it happened on. Some have theorized that it occurred later in 1752, while others have questioned whether it happened at all, or at least acknowledged that there is room for doubt.
“The episode of the kite, so firm and fixed in legend, turns out to be dim and mystifying in fact,” wrote Carl Van Doren in his 1939 Pulitzer Prize-winning biography, Benjamin Franklin . The legendary aspect of the kite and key experiment has led many people believe, incorrectly, that it marked the discovery of electricity.
Ben Franklin Didn't Discover Electricity
Electricity was already a known phenomenon during the mid-18th century. There were, however, debates about the nature of this phenomenon, and Franklin was one of a group of philosophers and scientists who theorized that lightning was a form of electricity.
In March 1750, Franklin wrote a letter to his friend Collinson about his idea for a lightning rod. That July, he published an idea for an experiment using a lightning rod to try and catch an electrical charge in a “leyden jar,” a storage container for electrical charges, thus demonstrating that lightning was a form of electricity.
Franklin’s ideas circulated in Europe, and in May 1752, two French scientists—Thomas Dalibard and M. Delor—separately carried out successful versions of Franklin’s experiment. According to Priestley, Franklin hadn’t yet heard of these successes in June 1752, when he was waiting on the construction of a spire to conduct his own lightning rod experiment.
Apparently, Franklin decided that instead of waiting for the spire, he could test his theory by flying a kite with a key attached to its string when he sensed an approaching thunderstorm. “[D]reading the ridicule which too commonly attends unsuccessful attempts in science, he communicated his intended experiment to noone but his son, who assisted him in raising the kite,” Priestley wrote.
Ben Franklin Didn't Get Struck By Lightning
So what would this experiment have actually looked like? Although many artists have tried to depict it, “most of the pictures and drawings that you see depicting Franklin in this experiment are inaccurate,” says Harold D. Wallace Jr. , a curator in the division of work and industry at the Smithsonian National Museum of American History.
“They show Franklin standing out in the middle of a field,” he says, “whereas most likely he and William were inside some kind of shed or lean-to or something to keep them from getting rained on, in case the rain did start.” (Franklin likely started the experiment after sensing lightning in the air, but before any rain began to fall, says Wallace.)
Franklin’s goal probably wasn’t for the kite and key to get struck by lightning; and indeed, Priestley never claimed that they were struck by lightning. If they had been , Franklin would’ve almost certainly died or at least been seriously injured (in 1753, the German scientist Georg Wilhelm Reichmann died while trying to conduct Franklin’s lightning rod experiment).
What probably happened is that the key picked up some ambient electrical charge from the storm. Priestley wrote that Franklin touched the key and felt the charge, confirming he had caught some electricity from the lightning.
Even if Franklin never actually performed the kite and key experiment, he did come up with the lightning rod idea that others tested. Together, these experiments helped prove that lightning was a form of electricity that people could harness, both to protect tall buildings from damage and to perform more experiments.
“The idea of mitigating natural dangers is such a big game changer,” says Michael Madeja , head of education programs at the American Philosophical Society Library and Museum. “The lightning rod also helped provide a decent source of charge for things like leyden jars or other electrical experiments.”
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The kite experiment, 19 october 1752, the kite experiment.
I. Printed in The Pennsylvania Gazette , October 19, 1752; also copy: The Royal Society. II. Printed in Joseph Priestley, The History and Present State of Electricity, with Original Experiments (London, 1767), pp. 179–81.
Franklin was the first scientist to propose that the identity of lightning and electricity could be proved experimentally, but he was not the first to suggest that identity, nor even the first to perform the experiment. 4 For many years pioneer electricians had noted the similarity between electrical discharges and lightning, and in 1746 John Freke in England and Johann Heinrich Winkler in Germany separately advanced the idea of identity and suggested theories to account for it. Franklin’s later adversary the Abbé Nollet wrote to the same effect in 1748. 5 Franklin and his Philadelphia collaborators, working independently, also observed the similarities, and in his letter of April 29, 1749, to John Mitchell on thundergusts he took as the basis for his entire discussion the hypothesis that clouds are electrically charged. 6 In the “minutes” he kept of his experiments he listed under the date of November 7, 1749, twelve particulars in which “electrical fluid agrees with lightning,” and noted further that “the electrical fluid is attracted by points,” but that it was not yet known whether this property was also in lightning. “But since they agree in all other particulars wherein we can already compare them, is it not probable they agree likewise in this? Let the experiment be made.” 7
However obvious the suggestion of such an experiment may now seem, no one had made it before. Herein lies Franklin’s principal claim to priority in this great discovery. A test of lightning required the prior discoveries embodied in the “doctrine of points,” of which he was the undisputed author, and the knowledge he had gained of the role of grounding in electrical experiments. It was the pointed metal rod, with its peculiar effectiveness in electrical discharge, which both led to the suggestion and facilitated the experiment.
In the following March Franklin, writing to Collinson, suggested that pointed rods, instead of the usual round balls of wood or metal, be placed on the tops of weathervanes and masts, and that they would draw the electrical fire “out of a cloud silently,” thereby preserving buildings and ships from being struck by lightning. 8 He repeated the suggestion in July 1750 in his “Opinions and Conjectures,” with the important addition that a wire be run down from the rod to the ground or water, and he then proposed the “sentry-box” experiment. This was the first public suggestion of an experiment to prove the identity of lightning and electricity. 9
According to Joseph Priestley, who almost certainly received his information directly from Franklin about fifteen years later, he did not perform the experiment himself at once because he believed a tower or spire would be needed to reach high enough to attract the electrical charge from a thunder cloud, and there was no structure in Philadelphia he deemed adequate for the purpose. Presumably he was waiting until Christ Church steeple, then in the early discussion stage, should be erected. 1 English scientists, who could have read Franklin’s proposal when it was published in Experiments and Observations in April 1751, apparently failed to recognize its significance. But about a year later, in the spring of 1752, when a translation had been published in Paris, the French reaction was very different. Delor, “master of experimental philosophy,” repeated most of Franklin’s experiments before the King, and then in May Dalibard, Franklin’s translator, and Delor each set up apparatus which performed successfully the “Philadelphia experiment” of drawing electricity from a thunder cloud. 2 Word of these achievements awoke the English electricians, and during the summer of 1752 the experiment was repeated several times in England as well as in France and Germany. 3
At some time during 1751 or 1752 Franklin got the idea that he could send his conductor high enough by means of a kite, and that if it were flown during a thunder shower, the wet string might serve to bring the electrical charge down within reach. When the idea first came to him and just when he carried it out cannot be established with absolute certainty. Priestley wrote that the famous experiment with kite and key took place during June 1752, and the present editors believe there is no good reason to doubt the correctness of this date. If so, then Franklin performed his experiment before he learned of what Dalibard and Delor had done in France.
Almost never during these years did Franklin report a particular electrical experiment until some time had elapsed and this affair seems to have been no exception. Word of Dalibard’s and Delor’s successes reached Philadelphia toward the end of August and the Pennsylvania Gazette of August 27 carried a short account reprinted from the May issue of the London Magazine . During September Franklin erected a lightning rod on his own house, ingeniously equipping it with bells that would ring when the wire became charged and thus notify him when the atmosphere above the house was electrified. 4 Then at last, on October 19, he printed in the Gazette a brief statement about the kite experiment with instructions for repeating it. The text of this statement, transmitted to Collinson, was read to the Royal Society on December 21. Neither in this paper nor at any later time did Franklin—or Priestley on his behalf—ever claim priority in carrying out the experiment he had been the first to propose. 5
The same October 19 issue of the Gazette also announced that Poor Richard for 1753 was then “In the Press, and speedily will be published”; in that almanac Franklin printed for the first time precise instructions for the erection of lightning rods for the protection of buildings. 6 The sequence of events in this somewhat complicated chain may be clarified by the following chronology:
Unfortunately, Franklin’s statement of the kite experiment has not been found in his own handwriting. Two text versions survive: that printed in the Pennsylvania Gazette of October 19, 1752, reprinted below; and a copy in the hand of Peter Collinson, now in the Royal Society. 7 Aside from unimportant variations in paragraphing, spelling, capitalization, and punctuation, the Collinson copy differs from the Gazette version in several respects: (1) It is headed “From Benn: Franklin Esqr To P Collinson” and is dated “Philadelphia Octo: 1: 1752.” (2) At the end, following the words “compleatly demonstrated,” Collinson skipped the equivalent of about three lines, then added in two lines: “See his Kite Experiment” and “to be printed with the rest.” These lines were later struck out. (3) In the intervening space and running on to the right of the two canceled lines appears the following insertion not in Collinson’s hand, but in one which is strikingly like that of William Watson: “I was pleased to hear of the Success of my experiments in France, and that they there begin to Erect points on their buildings. Wee had before placed them upon our Academy and Statehouse Spires.” (4) The paper is endorsed in the hand of a Royal Society clerk: “Letter of Benjamin Franklin Esq to Mr. Peter Collinson F.R.S. concerning an Electrical Kite. Read at R.S. 21 Decemb. 1752. Ph. Trans. XLVII . p. 565.”
These text differences present several puzzles. The heading and date (item 1) have led several writers 8 to believe that the text which follows is an extract of a letter from Franklin to Collinson of October 1, written more than two weeks before the statement was printed in the Gazette . In that case the Gazette text would be an extract from this earlier letter to Collinson. This is possible, but it leaves unexplained Franklin’s undated letter to Collinson, assigned below (p. 376) to the latter part of October, in which he wrote that he was sending, among other items, “my kite experiment in the Pennsylvania Gazette .” If what he had printed in the Gazette was indeed a passage from a letter already sent to Collinson, there would seem to have been no need to send him another copy of it. Conceivably, Collinson’s pen slipped when he wrote “Octo: 1,” as it occasionally did in referring to other Franklin letters, and he should have written “19,” “21,” or “31,” in which case he might have been copying the Gazette statement enclosed in Franklin’s later letter. Subsequent correspondence between the two men does not clarify the point.
The canceled addendum at the bottom (item 2) seems to have been intended as an instruction to a printer. Possibly Collinson first meant this paper for the printer of the 1753 Supplement of Experiments and Observations , and then decided to submit this copy to the Royal Society instead. But the question remains unexplained why he should have written “See his Kite Experiment,” when this document itself is the kite experiment, and is the only account of it we have in Franklin’s own words. The endorsement (item 4) presents no problem. The fact that the paper is lodged in the Royal Society makes it clear that this endorsement was added later for filing purposes after it had been printed in the Philosophical Transactions .
This leaves for consideration item 3, the short paragraph added to Collinson’s paper which mentions the French experiments and the erection of “points” in France and Philadelphia. The facts that it is written in a different hand from Collinson’s and that it is clearly an addition have not been considered by previous commentators. The paragraph has been taken as evidence that lightning rods were erected on the Academy building and the State House (Independence Hall) before October 1, 1752. The words are doubtless Franklin’s, though they have not been traced with certainty to any surviving document of his. If they were in fact part of a letter of October 1 to Collinson which also contained the original text of the statement on the kite experiment, then they must have been added to Collinson’s copy by someone else, probably Watson, who saw the original letter and thought this passage more important than Collinson had done. Or the paragraph may have been part of the later undated letter, probably of late October (the full text of which may not have been printed in the 1753 Supplement), with which Franklin enclosed the item on the kite experiment from the Gazette . Whatever the source, the paragraph must have been written by about November 1, 1752, in order for it to be read to the Royal Society as part of the report on the kite experiment on December 21 and printed as such in the Philosophical Transactions . 9 The probable date for the erection of the two Philadelphia lightning rods is not materially affected in any case. The problem of the source of this added paragraph is not resolved by any printed version of Franklin’s account. The Philosophical Transactions printed the text from Collinson’s copy. The Gentleman’s Magazine and London Magazine and the 1753 Supplement to Experiments and Observations also printed the report, but all three followed the dating and text of the Gazette version, not the Collinson copy. 1
It will be noticed that Franklin’s paper is not really an account of the kite experiment, but rather a brief statement that the experiment had taken place, followed by instructions as to how it could be successfully repeated. Franklin never, so far as is known, wrote out a narrative of his experience. The most detailed account that has survived is that which Joseph Priestley inserted in 1767 in his History of Electricity . There is every reason to believe that he learned the details directly from Franklin, who was in London at the time Priestley wrote the book. Franklin encouraged him to undertake the work and Priestley acknowledged in his preface the information Watson, Franklin, and Canton had supplied him. The account of the kite experiment, as Priestley wrote it about fifteen years after the event, may err in some details through faulty memory on Franklin’s part or misunderstanding on the Englishman’s, but it is probably correct in all major respects. In any case, since it is the nearest thing we have to a contemporary, first-hand account of one of the most famous episodes in Franklin’s career, it is reprinted here directly following Franklin’s statement.
I. Franklin’s Statement
Philadelphia, October 19
As frequent Mention is made in the News Papers from Europe, of the Success of the Philadelphia Experiment for drawing the Electric Fire from Clouds by Means of pointed Rods of Iron erected on high Buildings, &c. it may be agreeable to the Curious to be inform’d, that the same Experiment has succeeded in Philadelphia, tho’ made in a different and more easy Manner, which any one may try, as follows. 2
Make a small Cross of two light Strips of Cedar, the Arms so long as to reach to the four Corners of a large thin Silk Handkerchief when extended; tie the Corners of the Handkerchief to the Extremities of the Cross, so you have the Body of a Kite; which being properly accommodated with a Tail, Loop and String, will rise in the Air, like those made of Paper; but this being of Silk is fitter to bear the Wet and Wind of a Thunder Gust without tearing. To the Top of the upright Stick of the Cross is to be fixed a very sharp pointed Wire, rising a Foot or more above the Wood. To the End of the Twine, next the Hand, is to be tied a silk Ribbon, and where the Twine and the silk join, a Key may be fastened. This Kite is to be raised when a Thunder Gust appears to be coming on, and the Person who holds the String must stand within a Door, or Window, or under some Cover, so that the Silk Ribbon may not be wet; and Care must be taken that the Twine does not touch the Frame of the Door or Window. As soon as any of the Thunder Clouds come over the Kite, the pointed Wire will draw the Electric Fire from them, and the Kite, with all the Twine, will be electrified, and the loose Filaments of the Twine will stand out every Way, and be attracted by an approaching Finger. And when the Rain has wet the Kite and Twine, so that it can conduct the Electric Fire freely, you will find it stream out plentifully from the Key on the Approach of your Knuckle. At this Key the Phial may be charg’d; and from Electric Fire thus obtain’d, Spirits may be kindled, and all the other Electric Experiments be perform’d, which are usually done by the Help of a rubbed Glass Globe or Tube; and thereby the Sameness of the Electric Matter with that of Lightning compleatly demonstrated.
II. Priestley’s Account
To demonstrate, in the completest manner possible, the sameness of the electric fluid with the matter of lightning, Dr. 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. This kite had a pointed wire fixed upon it, by which it drew the lightning from the clouds. This lightning descended by the hempen string, and was received by a key tied to the extremity of it; that part of the string which was held in the hand being of silk, that the electric virtue might stop when it came to the key. He found that the string would conduct electricity even when nearly dry, but that when it was wet, it would conduct it quite freely; so that it would stream out plentifully from the key, at the approach of a person’s finger. 3
At this key he charged phials, and from electric fire thus obtained, he kindled spirits, and performed all other electrical experiments which are usually exhibited by an excited globe or tube.
As every circumstance relating to so capital a discovery as this (the greatest, perhaps, that has been made in the whole compass of philosophy, since the time of Sir Isaac Newton) cannot but give pleasure to all my readers, I shall endeavour to gratify them with the communication of a few particulars which I have from the best authority.
The Doctor, after having published his method of verifying his hypothesis concerning the sameness of electricity with the matter of lightning, was waiting for the erection of a spire in Philadelphia to carry his views into execution; not imagining that a pointed rod, of a moderate height, could answer the purpose; when it occurred to him, that, by means of a common kite, he could have a readier and better access to the regions of thunder than by any spire whatever. Preparing, therefore, a large silk handkerchief, and two cross sticks, of a proper length, on which to extend it; he took the opportunity of the first approaching thunder storm to take a walk into a field, in which there was a shed convenient for his purpose. But dreading the ridicule which too commonly attends unsuccessful attempts in science, he communicated his intended experiment to no body but his son, who assisted him in raising the kite. 4
The kite being raised, a considerable time elapsed before there was any appearance of its being electrified. One very promising cloud had passed over it without any effect; when, 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 knucle 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. This happened in June 1752, a month after the electricians in France had verified the same theory, but before he heard of any thing they had done.
4 . The best discussion of this entire topic is I. Bernard Cohen, “The Two Hundredth Anniversary of Benjamin Franklin’s Two Lightning Experiments and the Introduction of the Lightning Rod,” APS Proc , XCVI (1952), 331–66. The present editors are in full agreement with Cohen’s conclusions except, as this headnote will show, those derived specifically from consideration of the Collinson copy of BF ’s statement on the kite experiment.
5 . Cohen, BF’s Experiments , pp. 104–9, discusses the matter with citations and quotations from various writers.
6 . See above, III , 365–76.
7 . Quoted by BF in his letter to John Lining, March 18, 1755 , Exper. and Obser. 1769, p. 323. The originals of BF ’s minutes have not survived.
8 . See above, III , 472–3
9 . See above, pp. 19–20.
1 . See above, p. 116.
2 . See above, pp. 302–10, 315–17.
3 . See below, 390–2.
4 . BF to Collinson, September 1753.
5 . Writing in 1788 in his autobiography, BF mentions the Dalibard and Delor successes with the “Philadelphia experiments” and then adds simply and with disappointing brevity: “I will not swell this Narrative with an Account of that capital Experiment, nor of the infinite Pleasure I receiv’d in the Success of a similar one I made soon after with a Kite at Philadelphia, as both are to be found in the Histories of Electricity.” Par. Text edit., p. 386.
6 . See below, p. 408.
7 . The Collinson copy is reproduced in facsimile in APS Proc. , XCVI , pp. 334–5.
8 . Notably Cohen in the works cited in the first two footnotes to this headnote, and Carl Van Doren in Franklin , p. 169, and Autobiographical Writings , p. 76.
9 . The paragraph could be from some now missing letter of later date than about Nov. 1, 1752, only in the unlikely circumstance that it was added to the Collinson copy between the reading of the paper on December 21 and the transmission of this number of Phil. Trans. to the printer sometime in 1753.
1 . Gent. Mag. , XXII (1752), 560–1; London Mag. , XXI (1752), 607–8; Supplemental Experiments and Observations on Electricity, Part II (London, 1753), pp. 106–8. Gent. Mag. and the 1753 Supplement both add the initials “B.F.” at the end; London Mag. omits the first paragraph and begins “Make a small cross, …” but otherwise follows the Gazette version.
2 . In 1760 and later printed editions: “which is as follows:”
3 . At this point Priestley inserted a footnote reference to Exper. and Obser ., p. 106, where BF ’s statement is printed.
4 . At this time William Franklin was at least 21 years old (see above, III , 474), not the child shown in the well-known Currier and Ives print depicting the scene. There are a number of other errors in the picture.
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Did Benjamin Franklin really discover electricity with a kite and key?
Did the founding father really discover electricity?
On a dark, stormy summer night in 1752, Benjamin Franklin flew a kite with a key attached to the string waiting in anticipation for lightning to strike. The dramatic bolt would harken the discovery of electricity (or as Franklin called it "electrical fire") … or so the story goes.
But is there any truth to this tale? Did Franklin really discover electricity by getting zapped by a lightning bolt during this experiment?
Though most people know Benjamin Franklin — an American founding father, legendary statesman and the face of the U.S. $100 bill — for his political contributions, Franklin was well known in his time as a scientist and an inventor: a true polymath. He was a member of several scientific societies and was a founding member of the American Philosophical Society. As a result, he stayed informed on the most pressing scientific questions that occupied learned people of his time, one of which was the nature of lightning.
As for the kite-and-key experiment, most people are aware of the version in which the metal key acted as a lightning rod, and Franklin subsequently "discovered" electricity when lightning struck his kite. However, several details about this experiment are unknown, including when and where it happened. Some historians even doubt that it took place.
Related: Did Benjamin Franklin really want the turkey to be the US national bird?
For starters, it's a common myth that Franklin discovered electricity. Electricity had already been discovered and used for centuries before Franklin's experiment. Franklin lived from 1709 to 1790, and during his time, electricity was understood as the interaction between two different fluids , which Franklin later referred to as "plus" and "minus." According to French chemist Charles François de Cisternay du Fay, materials that possessed the same type of fluid would repel, while opposite fluids attracted one another. We now understand that these "fluids" are electrical charges generated by atoms. Atoms are made up of negatively charged electrons orbiting a positively charged nucleus (made up of protons and neutrons).
It was unknown prior to Franklin's experiment whether lightning was electrical in nature, though some scientists, including Franklin, had speculated just that . Page Talbott, author and editor of " Benjamin Franklin: In Search of a Better World " (Yale University Press, 2005) and the former president and CEO of the Historical Society of Pennsylvania in Philadelphia, said that Franklin was particularly interested in this question because lightning strikes had caused disastrous fires in cities and towns where houses were made of wood, which many homes in the U.S. were at the time. "By attaching a key to the string of a kite, thus creating a conductor for the electrical charge , he was demonstrating that a pointed metal object placed at a high point on a building — connected to a conductor that would carry the electricity away from the building and into the ground — could make a huge difference to the long-term safety of the inhabitants," Talbott told Live Science in an email. In other words, by creating a lightning rod, Franklin was helping to protect wooden homes and buildings from being directly struck by lightning.
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Lightning rods are metal rods placed at the top of structures, connected to the ground with a wire. If lightning strikes the building, it will likely strike the electrically conductive rod instead of the building itself and safely run through the wire to the ground.
Here's how the experiment worked; standing in a shed, Franklin flew a kite, made of a simple silk handkerchief stretched across a cross made of two cedar strips, during a lightning storm. The tail of the kite was made of two materials — the upper end attached to the kite was made of hemp string and attached to a small metal key, while the lower end, held by Franklin, was made of silk. The hemp would get soaked by the rain and conduct electrical charge, while the silk string would remain dry because it is held under cover.
As Franklin observed his flying kite, he saw that the hemp strands stood on end as they began to accumulate electrical charge from the ambient air. When he placed his finger near the metal key, he reportedly felt a sharp spark as the negative charges that had accumulated on the key were attracted to the positive charges in his hand.
A few publications at the time reported on the experiment. "[Franklin] published a statement about the experiment in the Pennsylvania Gazette , the newspaper he published, on October 19, 1752," Talbott said. He then sent the text of this statement to a patron of the American Philosophical Society named Louis Collinson; Franklin had spent the last few years communicating his theories and proposing his experiments concerning lightning to him.
Franklin referred to the experiment in his autobiography, and other colleagues in Europe wrote about it as well, Talbott said. Notably, the experiment appeared in the 1767 book " History and Present Status of Electricity " by Joseph Priestley, an English chemist. Priestley heard about the kite-and-key experiment from Franklin himself around 15 years after the fact, and in his book, he wrote that it occurred during June 1752. However, exactly when the experiment came to Franklin and when he did it is a matter of debate.
There are some historians who doubt whether Franklin actually did the experiment himself, or merely outlined its possibility. In his book " Bolt of Fate: Benjamin Franklin and His Electric Kite Hoax " (PublicAffairs, 2003), author Tom Tucker stated that Franklin wanted to thwart William Watson, a member of the Royal Society of London and a preeminent electrical experimenter. Watson had sabotaged the publication of some of Franklin's previous reports and had ridiculed his experiments in the Royal Society, Tucker wrote. Could Franklin have felt pressured to invent the kite story to get back at Watson?
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Tucker also noted that Franklin's description of his experiment in the Pennsylvania Gazette was phrased in the future conditional tense: "As soon as any of the Thunder Clouds come over the Kite, the pointed Wire will draw the Electric Fire from them..." Franklin could have simply been saying that the experiment could, in theory, be performed. Given that his statement has a few missing details — Franklin didn't list a date, time or location, for example — it's possible that the American diplomat did not perform the experiment himself.
However, some historians remain unconvinced that the experiment wasn't carried out, pointing to Franklin's great respect for scientific pursuits . Franklin experts, such as the late American critic and biographer Carl Van Doren, also point to the fact that Priestley specified the month in which Franklin performed his experiment, suggesting that Franklin must have given him precise details directly.
Originally published on Live Science.
Jacklin Kwan is a freelance journalist based in the United Kingdom who primarily covers science and technology stories. She graduated with a master's degree in physics from the University of Manchester, and received a Gold-Standard NCTJ diploma in Multimedia Journalism in 2021. Jacklin has written for Wired UK, Current Affairs and Science for the People.
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Franklin's electrostatic machine is a high-voltage static electricity-generating device used by Benjamin Franklin in the mid-18th century for research into electrical phenomena.
The kite experiment is a scientific experiment in which a kite with a pointed conductive wire attached to its apex is flown near thunder clouds to collect static electricity from the air and conduct it down the wet kite string to the ground.
Electrical forces had been recognized for more than a thousand years, and scientists had worked extensively with static electricity. Franklin’s experiment demonstrated the connection between lightning and electricity.
In this video, we talk about how Benjamin Franklin contributed to the understanding of static electricity through his weird experiments with glass and rubber rods. The discovery of different...
Franklin’s strategy for the June 1752 experiment —inspired, perhaps, by that avian accident—was to fly a kite with a wire pointing up from its top near a passing thundercloud. He reasoned that...
Benjamin Franklin left an important legacy in electrical science and its useful application to mankind. The experiments published in “ Experiments and Observations on Electricity Made at Philadelphia in America” proved the existence of positive and negative charges as well as the concepts of insulators and conductors.
Get a bit of the history of electricity with a story about Benjamin Franklin and how he discovered static electricity through his strange obsession with rubbing glass and hard rubber with silk and fur.
On June 10, 1752, Benjamin Franklin took a kite out during a storm to see if a key attached to the string would draw an electrical charge. Or so the story goes. In fact, historians aren’t...
Franklin was the first scientist to propose that the identity of lightning and electricity could be proved experimentally, but he was not the first to suggest that identity, nor even the first to perform the experiment. 4 For many years pioneer electricians had noted the similarity between electrical discharges and lightning, and in 1746 John Fr...
On a dark, stormy summer night in 1752, Benjamin Franklin flew a kite with a key attached to the string waiting in anticipation for lightning to strike. The dramatic bolt would harken the...