On June 10 1752, at the age of 47, Ben Franklin conducted his famous kite experiment. Rather than me [poorly] paraphrasing a brief article on it, I'll copy/paste it here for your enjoyment. Benjamin Franklin and the Kite Experiment From The Franklin Institute 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.”
Good piece John. Too bad they didn’t video tape it. Ben missed a good op for his YouTube channel. Seriously though, I didn’t even know Ben had a son and I’m glad that the article established the fact of what his experiment with a kite really discovered.
I recall all of the paintings of the event had his kid in it, and it always struck me that Ben was portrayed as looking elderly when he was only 47 years old. I found it interesting that Ben had enough of a concept of electricity to have the conductive hemp wound around an insulated silk string that he held on to.
At 47 in colonial days, he might have looked a little old especially with the long hair thing going on. That said, for a guy who only had a couple of years of formal education, he did show some genius on a few levels.
Only one problem with this write up but it also helps to understand why the information and his conclusions with the flow of electricity were wrong. Current does not flow ground to positive just the opposite. That was learned later by Ben. The problem was all the great write ups and books after his discoveries were already written it would have cost a fortune to reprint all the written material. He was a Printer by trade but to print in his time was extremely costly. The flow has nothing to do with the math and nothing changed but few people know about the mistake due to no corrections made.
I learned in the service that there is conventional current flow and electron current flow. In the end, it doesn't really matter what you use. "Current is flow of electrons, but current and electron flow in the opposite direction. Current flows from positive to negative and electron flows from negative to positive. Current is determined by the number of electrons passing through a cross-section of a conductor in one second."
I believe I already said the same, the math is the same ! The flow direction is not what Ben initially wrote in all his papers and even today it is not corrected in the teaching or instructions for electronics. Your battery in the car does not flow negative to positive but the opposite. Very few books actually mention this but there are a few out there that cover the facts and history. Negative electrons moving in the opposite direction make up current, but it makes no difference. Swap your volt meter leads pos to neg and you see that minus sign, but the voltage is the same. Before 55 all 6 volts systems in our cars were positive ground.
I like Ben Franklin. I saw the Ken Burns documentary recently. I enjoyed it. I remember going to Philadelphia decades ago. I seem to recall passing by his grave.
Hey, Sam. Welcome to the club. I spent many years in Virginia, right outside of DC, but never made the trip to Philly to see any of the Franklin stuff. I did spend a lot of time at the Smithsonian museums, where I'm sure there were some Franklin exhibits in the National Museum of American History and the National Museum of Science and Technology. He's buried in the Christ Church Burial Ground with 4 other signers of the Declaration of Independence. Franklin's grave:
yes, that does look familiar... grew up in Jersey. I've been in Philly a number of times. Been in DC less than ten times..but loved it every time. Smithsonian once or twice. But a long time ago. Mostly back in the 70s. I guess it is sad, but the first thing I remember about DC was this amazing soul food restaurant that my wife and I went to. Have only done soul food a few times and that time was amazing. We also went to a great steak place. A bunch of John McCain's staff members were there at the time. All very nice, very respectful people. Younger than I had imagined. A bunch were in their 20s. I think what they say in the news is different than what is the reality. Just absolutely normal, nice folks. When I grew up, I grew up around folks from both sides of the aisle. No fights, everyone respected each other. Different time. My block growing up was probably evenly split between conservatives and liberals. And everyone got along. No fights. I don't know what happened to change that, but I do know it is not good. And, of course, the Lincoln Memorial, Jefferson Memorial...so impressive. All of it really...the Supreme Court building...all that marble. The National Gallery, Library of Congress...