File Name: experiments and observations on electricity benjamin franklin .zip
This short essay is not about electricity in the strict sense, but about the context in which Franklin presented some of his work in science and in politics in , and about the way that work was received in Britain. The aim of the essay is to suggest that Franklin was neither a child of the British or European Enlightenment nor one of its toys. And though he may have been touted very generally as an inspiration, he was closer to a foreign force with which, intellectually as well as a politically, it had to contend. This may help in explaining why he proved so considerable a foe to the British state. Obstinacy, obtuseness, complacency, poor judgment, bad luck?
The connection between electricity and lightning was known but not fully understood. By conducting the kite experiment Franklin proved that lighting was an electrical discharge and realized that it can be charged over a conductor into the ground providing a safe alternative path and eliminating the risk of deadly fires.
Franklin hypothesized that lightning was an electrical discharge. Before he thought of conducting his experiment by flying a kite, he proposed erecting iron rods into storm clouds to attract electricity from them.
He also suggested that the tips of the rods should be pointed instead rounded so that they could draw electrical fire out of a cloud silently. Philadelphia has a flat geography and at the time there were no tall structures, he was anxiously waiting for the construction of Christ Church that was being built on a steeple to conduct his experiment.
Franklin wrote his proposal for the iron rod experiment in a letter to Peter Collison who was a member of the Royal Society of London. Franklin was recognized by the Royal Society of London and in scientific circles all over Europe, becoming the most famous American in Europe. Franklin kept himself and the end of the string dry to protect himself from being electroshocked.
Franklin had not heard of the success of his experiment in Europe before he conducted the same experiment with a kite. One day in June , it occurred to him that he could test his hypothesis by flying a kite instead of waiting for the church to be built.
With the help of his son William he built the body of the kite with two crossed strips of cedar wood and a silk handkerchief instead of paper as it would not tear with wind and rain. They attached a foot long sharp and pointed wire to the top of the kite as a conductor and at the bottom end of the string where it is held they attached a silk ribbon and a metal key. A metal wire connected the key to the Leyden Jar.
Franklin kept dry by retreating into a barn; the end of the string was also kept dry to insulate himself. When the stormed passed over his kite the conductor drew electricity into his kite. The kite was not struck by lightning but the conductor drew negative charges from a charged cloud to the kite, string, metal key and Leyden jar.
It appears that he knew enough about grounding to protect himself from being electroshocked. When he moved his hand near the key he received a shock because the negative charge attracted the positive charge in his body. 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. It has pleased God and his goodness mankind, at length to discover to them the means of securing their habitations and other buildings from mischief by thunder and lightning.
The method is this: Provide a simall iron rod but of such a length that one end being three or four deet in the moist ground, the other may be six or eight feet above the highest part of the building. To the upper end of the rod fasten about a foot of brass wire, the size of a common knitting needle, sharpened to a fine point; the rod may be secured to the house by a few small staples.
If the house or barn be ling, there may be a rod and point at each end, and a middling wire along the ridge from one to the other. A house thus furnished will not be damaged by lightning, it being attracted by the points and passing thro the metal into the ground without hurting anything.
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Boston: Printed and Sold by S. Kneeland in Queen-Street. Yale University Library. Franklin wrote the essay in Franklin included it in the fourth edition of his Experiments and Observations on Electricity , Adam Smith is known to have had two copies of the essay in his library.
In Benjamin Franklin helped draft the Declaration of Independence and soon after set sail for Paris, sent by the Continental Congress to negotiate a treaty with the French. He was already one of the eight foreign associates of the French Academy of Sciences a century would pass before another American got this rare honor. As the "Newton of electricity" whose theories, experiments and lightning rods were known the length of Europe, Franklin was given a respectful hearing. He became perhaps the chief factor in winning the support of the French government and its fleet, support which proved decisive in the War for Independence. If Franklin the diplomat could achieve so much, it was largely because first he was Franklin the scientist.
Jump to navigation. On a June afternoon in , the sky began to darken over the city of Philadelphia. 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.
Experiments and Observations on Electricity is a mid-eighteenth century book consisting of letters from Benjamin Franklin. These letters concerned Franklin's discoveries about the behavior of electricity based on experimentation and scientific studies. The book came in pamphlet form for the first three English editions. The last two editions were in a book volume with hard covers and a book spine. There were eleven European editions of the book: five English editions, three French editions, and a German, Italian and Latin edition.
The connection between electricity and lightning was known but not fully understood. By conducting the kite experiment Franklin proved that lighting was an electrical discharge and realized that it can be charged over a conductor into the ground providing a safe alternative path and eliminating the risk of deadly fires. Franklin hypothesized that lightning was an electrical discharge. Before he thought of conducting his experiment by flying a kite, he proposed erecting iron rods into storm clouds to attract electricity from them. He also suggested that the tips of the rods should be pointed instead rounded so that they could draw electrical fire out of a cloud silently.
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Franklin began his experiments on electricity in the s and communicated his results to correspondents in Great Britain. In , these various letters were compiled into this book. Experiments and observations on electricity. Printed and sold by E. Cave, at St. John's Gate.
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