Benjamin Franklin's Lightning Rod
When Benjamin Franklin invented the lightning rod to save lives and buildings, he had no idea that he would also conquer Satan.
One dark stormy day in June of 1752, 46-year-old Benjamin Franklin took a walk with his 21-year-old son, William, into a field near the banks of the Schuylkill to fly a kite. Trusting in his father's scientific know-how, William probably had little idea that he was participating in a potentially life-threatening experiment
As part of his scientific research with electricity, Franklin was intrigued by electrical storms. So much so, that he designed an experiment to study the lightning generated by storms. In a fashion, we can probably dub Franklin as, "the world's first official storm chaser."
As the legendary story goes, Franklin attached a piece of metal wire to his homemade kite in order to help attract electrical charges flying across the overhead clouds. As the hemp string played out through Franklin's fingers, the kite twisted and turned in the turbulent winds as it soared higher and higher. After a considerable length of the string had played out, Franklin used a piece of silk ribbon to tie a key to the string. Then, with great apprehension, he waited with William patiently standing nearby to see what would happen.
Whether it was a collection of static electricity gathered along the moist hemp string or a "gentle" lightning strike, we may never know. Regardless, Ben Franklin reported that he received a jolt of electricity when he reached out and positioned his hand near the key.
"The rest," as is often said, "is history." And, even though Franklin and his son, William, survived this experiment. There have been others who have tried to duplicate this experiment, and have lost their lives, or, crippled their minds and/or bodies.
Long before his famous kite-flying experiment, Franklin believed that lightning and static electricity shared similarities. While living in Boston in 1746, Franklin set up a laboratory to conduct his "electrical amusements."
At the time, there were other scientists in Boston conducting electrical experiments. It was in 1746, during his first year of conducting electrical experiments, that Franklin suffered a not-too-amusing jolt of electricity. In a letter to a friend he expressed the shocking experience as, "... a universal blow throughout 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." As a result of this electrical shock, Franklin experienced numbness in his arms and the back of his neck for a few days.
As Franklin continued to conduct his electrical experiments, he wrote down his efforts and shared them in letters written to Peter Collinson in London. Collinson was a friend and scientist who shared an interest in Frankin's experiments. In 1749, Franklin sent a letter to Collinson describing the concept of a electrical battery that could hold a charge for a brief period of time. In the same letter, Franklin expressed doubts as to how such an invention could be of service to humankind.
During Franklin's experiments, he observed that when glass was rubbed, it became "filled" with an electrical charge, making it "positively charged." He also observed that when other objects, such as amber, were rubbed, electricity flowed out from them, and therefore they became "negatively charged." This designation by Franklin of "positive" and "negative" electrical charges established a new base language for understanding electricity that has remains with us to this day. Prior to Franklin's time the words "vitreous" and "resinous" were used to express the charges of electricity.
In his experiments, Franklin observed that when certain objects were "filled" with static electricity, they would discharge a "spark" of electricity when placed near a pointed metal needle. Franklin was not the first to speculate about a relationship between lightning and the harmless sparks created by static electricity. William Wall, a British scholar had suggested such a relationship in 1708.
However, Franklin was the first to propose an experiment of using a lightning rod on top of a building to capture the "fire" from the clouds. The first lightning rod described by Franklin was an iron rod 8 to 10 feet in length that came to a sharpened point on it uppermost tip.
Two years prior to his kite experiment, Franklin conducted experiments where he used a large sharp iron needle to draw electricity away from a charged metal sphere. Through his observations, Franklin extrapolated the results to his invention of the lightning rod to protect the tops of buildings. In 1750 he wrote to a friend, "May not the knowledge of this power of points be of use to mankind, in preserving houses, churches, ships, etc., from the stroke of lightning, by directing us to fix, on the highest parts of those edifices, upright rods of iron made sharp as a needle... Would not these pointed rods probably draw the electrical fire silently out of a cloud before it came nigh enough to strike, and thereby secure us from that most sudden and terrible mischief?"
Even though Franklin's lightning rod proposal was first published in England by the Royal Society of London in 1751, it was someone in France who had the nerve and wherewithal to attempt the experiment in the spring of 1752. When the French lightning rod experiment worked according to Franklin's theory, the King of France sent a message to Franklin expressing his compliments. However, due to the slow transit of mail in those days, Franklin did not receive the French King's message until August of 1752, two months after Franklin had already proved his theory by successfully using the dangerous kite and key rig.
In June of 1752, Franklin was in Philadelphia watching the progress of a steeple being built on top of the Christ Church. Franklin was going to use this steeple for his first lightning rod experiment.
From these "electrical amusements," Franklin speculated further that the placement of a pointed iron "rods" on top of buildings would prevent lightning from causing fires. He figured fires could be prevented because the pointed rod would capture the lightning's "fire sparks." On this note, Franklin was half right. Eventually, sometime in 1753, Franklin figured out that all lightning rods need to be "grounded." He accomplished this by using a metal wire or cable to draw the charge from the lightning rod, and to harmlessly guide the electric charge down into the ground away from the structure.
Before Franklin's invention, lightning destroyed or damaged many buildings. The invention of the lightning rod immediately reduced the number of buildings being struck by lightning across the colonies and Europe. The rapid and widespread use of lightning rods quickly reduced the number of fires. This fact alone helped governments and the public to better appreciate the practical applications of Franklin's scientific research into electricity. Especially, when one considers the antiquated firefighting apparatus available in the 1700s. In Franklin's time, entire towns were known to burn down as the result of fires ignited by lightning strikes.
Buildings, such as those with tall spires or constructed on promontory points - like churches; lighthouses; mansions, and commercial buildings - were all susceptible to lightning strikes. Once outfitted with lightning rods, these tall structures were less likely to be struck and damaged by lightning. The tangible reality of Franklin's invention saving lives, homes and buildings made him an international celebrity and a respected scientific genius.
Prior to Franklin's studies of electricity and his lightning rod invention, most European and American people associated lightning strikes to be associated with selective punishment by God. Thunderstorms and lightning were considered as "evil" and sourced from "Satan." Terms identified with Satan include in the Book of John 12:31, 14:30; "the prince of the power of the air" also called Merriam.
One popular belief held by many early church leaders was that the ringing of consecrated holy bells was a way to use God's power to ward off Satan's approaching thunderstorms and lightning bolts. The irony of this belief is that the metal bells in the bell towers actually attracted lightning, which often killed or maimed the bell-ringers. The high death toll of bell-ringers from thunderstorms became so high, that In 1786, the Parliament of Paris passed a law making "... the custom of ringing church bells during storms illegal on account of the many deaths it caused to those pulling the ropes."
Peter Ahlwardts, the author of, "Reasonable and Theological Considerations about Thunder and Lightning" (1745), published information based on anecdotal stories and his personal observations. Ahlwardts' book advised people to stay away from buildings with tall steeples, such as churches, during thunderstorms, in order to avoid being struck by lightning. At the time, Ahlwardt's book was considered somewhat heretical.
On another note, many religious leaders found displeasure with Franklin's invention, and considered it as an affront to their belief systems. So much so, that Franklin's lightning rods installed on spires in Boston was blamed for the earthquake of 1755. At the time, Reverend Thomas Prince, who was pastor of Boston's Old South Church, made a note in his sermon intimating the frequency of Boston earthquakes may be the direct result of "iron points invented by the sagacious Mr. Franklin." Reverend Prince's statement was based on his opinion that "... in Boston are more erected [lightning rods] than anywhere else in New England, and Boston seems to be more dreadfully shaken. Oh! there is no getting out of the mighty hand of God.''
The invention of the lightning rod was helpful in educating people about the scientific basis of lightning relative to storm clouds and thunder. Once understood, people became aware of lightning as a natural phenomenon generated by storms through the action of churning water molecules within clouds. On similar note, this new understanding removed the stigma that being struck by lightning as a sign of God's selective punishment. Franklin's experiments proved that being struck by lightning was the unfortunate result of a random act in nature.
Franklin believed that his creation of the lightning rod was his greatest and most useful invention for the benefit of humankind. In spite of Franklin's apparent habit of keeping records and sharing his experiments through his letters, it is of historic interest that he never documented his kite experiment or wrote letters about the event. The only witness to the kite experiment was his son, William. And, the only written account of the kite and key experiment was by another person some 15 years after the event took place.
Franklin's lightning rod design was of an iron rod honed to a sharp point on its skyward tip. This design probably originated from his laboratory experiments using an oversized needle with a sharpened point. When pointed lightning 8 rods began being installed in parts of Europe and America, King George III had his palace in England protected with a blunt lightning rod, which he believed to be superior to Franklin's. Also, it was a matter of national pride, whereby the king was trying to demonstrate England's superiority.
Since 1752, there have been many opinions put forth as to which lightning rod design was superior - King George's blunt rod or Franklin's pointed rod. In 2003, the controversy as to which lightning rod was most effective was put to the test. When it came to capturing and safely routing a lightning strike to the ground, it was determined that the blunt lightning rod was more effective. Even though Franklin's design did not win this competition, Franklin still deserves credit for bringing this invention to the service of humankind.
Today, over 250 years after Franklin's invention, only a minority of industrial and commercial buildings use lightning rods, and less than 10% of American homes are effectively protected. According to C. Andrew Larsen, executive director of the Lightning Protection Institute, Arlington Heights, Illinois, "... about "80% to 90% of lightning rod installations are ordered after a catastrophe... scores of lives and billions of dollars in property could be saved each year if buildings were properly protected against lightning."
Considering that the average lightning strike carries a whopping 30-million volts, we are fortunate for the blessings bestowed by Benjamin Franklin's lightning rod invention.
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