Who invented the light bulb? A long history 1705-1809
Imagine, you happened to fall back in time to November 1705 and imagine you happened to be admitted to the lecture hall of the Royal Academy in London, then you could have seen an incredible sight: Isaac Newton’s 45-year-old assistant named Francis Hauksbee (who was an expert in vacuum pumps) demonstrating a strange device, with a glass tube on a spindle that he could spin with a handle. Then the room would be dramatically darkened, and Hauksbee spun his glass and placed his hand on the spinning tube, and the tube glows with an eerie purple light that was, according to Hauksbee bright enough to read large print with and be seen from 10 feet away! Unfortunately, purple doesn’t film well, so the film of this demonstration looks weaker than in reality but it is still cool as you can see from this BBC film. How did this light bulb work, why did Hauksbee think of it and how did this evolve to create the battery and the first bright electric lamp? Let me be your time traveler guide, James Burke Connections style. Ready? Let’s go!
Back in 1705, Hauksbee explained his reasoning: in preparation for this lecture, he had read an article where a French scientist had noticed that the top of a barometer would glow when shaken. Since a barometer was just a vial of mercury upended so that the top of the tube was a vacuum, Hauksbee figured that dropping mercury in a vacuum would glow when shaken. He, therefore, put a few drops of mercury in a glass tube and pumped out the air, and found that he was correct: when he shook it, this combination glowed. Then, to make it easier to shake, he put his tube on a spindle, which is how he discovered that placing his hand on the spinning tube to stabilize it made a significantly brighter light. Finally, Hauksbee realized that by rubbing a spinning glass tube he was making a lot of static electricity, which he demonstrated in a separate spinning glass with threads in it that would become attracted to the outside of the sphere. Hauksbee just needed to add fluorescent crystals to his globe to absorb the UV and purple light and emit nice white light and then he would have made a fluorescent light bulb, a light bulb that he had powered with electricity! Static electricity. Back in the present day, you can even “light” a fluorescent bulb with the static electricity of cling wrap Like this.
Then, 26 years after Hauksbee’s bulb, when a rival of Hauksbee’s named Steven Gray accidentally discovered that electricity can travel when he rubbed a glass tube and a feather stuck to a cork in the tube instead of the tube. Soon, Gray was picking up objects at great distances and discovered that some objects conduct electricity (conductors) and some don’t (insulators) and if you want stuff to stay electrified you better hang it up with insulators like silk. To demonstrate this, Gray took a young boy and hung him up with silk thread, electrified him with a charged tube, and watched as small objects floated up to the child’s hand like magic. I would like to show you another clip from the BBC which was beautifully done but has some factual mistakes, including stating that Gray used a Hauksbee machine on his flying boy when he really just used a charged rod. See, worth watching. Gray then interested a French scientist named Charles Du Fay in electricity and Du Fay accidentally discovered that a feather can dance between two rubbed objects if they are made of different materials and decided that there are two types of electricity. In determining which category everything fell into, he determined that every solid object (even conductors) could stay electrified if it was on an insulating stand. Du Fay was read by a German man with a flair for the dramatic named Matthias Bose who got bored with rubbing tubes by hand and came up with the idea of charging objects on stands with a Hauksbee machine. After writing a bad poem about how great he was, Bose then decided to use people on stands that he electrified with a Hauksbee’s machine for human electrical experiments. For example, Bose would electrify women with a hauksbee machine and then have men give them “shocking” kisses, or electrify himself and then have a spark from his hand light alcohol on fire. Bose even created a light bulb that was in the form of a crown and would spark and glow when near an electrified plate. Meanwhile, the king of France was so fascinated with these kinds of demonstrations that he elevated his son’s tutor, Abbe Nollet (who had been Du Fay’s assistant), to be the resident “electricity demonstrator at Versailles” (although it wasn’t exactly an official title), and Nollet created globes filled with different gasses that would spark when touched in a beautiful manner. These experiments became even more shocking when a friend named Pieter von Musschenbroek from Leyden, Denmark sent him a story of how a jar full of water could store electricity from a Hauksbee machine and give it out in such a rush that he wrote: “I thought I was done for[i].” And that he only “survived by the grace of God, [I would not] do it again for all the kingdom of France”. Challenge accepted! Nollet immediately used these “Leyden jars” to shock everyone, including 200 monks at a time, and made a bit of money on the side selling Leyden jars to other electrical wizards!
Meanwhile, in America, young Benjamin Franklin became obsessed with electricity saying that “I never was before engaged in any study that so totally engrossed my attention and my time. my Friends… come continually in crowds to see them, I have, during some months past, had little leisure for anything else.[ii]” Franklin built his own “hauksbee” machine that used a brush to rub the glass instead of a person and found that a volunteer could get electrified by touching either the glass or the brush but not both, and, as brushes pick up dirt, decided that the brush picked up the electrical fire so it was positive, and the glass lost electrical fire which he called negative. Franklin also made a lot of unique “electricity devices” including a special frame that had gold foil that would spark and glow as the electricity flowing through it, one of the first examples of incandescence. Franklin then discovered that electrical sparks tended to come from and go to sharp points over smooth surfaces and wondered that if, as he thought, a lightning cloud was full of electricity, then maybe a sharp tall metal stick could silently drain storm clouds of their “electrical fire” and save humans from their “mischief”. But first, he had to prove that lightning was electric, which he theorized he could do with a large metal stick that wasn’t stuck on the ground with a little point or kink in it, if a person could get electricity from that pole during a thunderstorm, then the pole must be draining electricity from the clouds, and lightning must be the same as electric sparks they could get at home, just on a much bigger scale.
In France, Abbe Nollet, the king’s electrician, was also a priest (Abbe means friar), thought Franklin’s theory of electricity was rubbish, sparks were sparks and lightning was a judgment from God. So, some enemies of Nollet’s decided to take up the challenge and try to steal electricity from the clouds, to try to humiliate France’s premier electrician with the theory from a yokel from the English colonies. And on May 10th, 1752, in Marley France, that is what they did. In October, Franklin wrote to the paper about how he had heard, “from Europe of the success of the Philadelphia experiment for drawing the electrical fire from clouds by means of pointed rods” but that he had done it in “a different and more easy manner” with a kite. [Side note: they didn’t actually drain the clouds, the bars were charged with inductance, as the electrons in the top of the spikes were repelled by the charges in the cloud – but it still worked, if it was hit by lightning, they would have been killed]. Abbe Nollet was still upset, and he and other religious leaders railed against lightning rods.
In Bologna, Italy, scientist Laura Bassi who had the town’s only Hauksbee machine, also became the first in town to recreate the “Marley Experiment” of getting lightning from the clouds. However, when she and her husband tried to install lightning rods there were riots, and they had to take them down! Bassi, who was allowed to earn her Ph.D. to attract attention to the town, wasn’t allowed to actually teach at the university so she instructed her students at home where she was free to teach about Franklin’s theories with her electricity machine and an outdoor atmospheric electricity setup, which is how her student Luigi Galvani, who was a biologist, learned about electricity. Twenty years later, Luigi Galvani and his wife, Laura (who was also a biologist) bought their own Hauksbee machines to electrify animals. One day, they had placed a dead dissected frog on the table for an anatomy lecture when an assistant accidentally (or as a lark) touched the dead frog leg with an electrified prong and he was shocked to find the dead frog jump! They were therefore galvanized (which is the origin of the term) to electrify every dead animal they could find and decided that all life is electric. Then, they took the dead frogs outside to make them jump in a storm when one day, it jumped on a calm day, and they realized that it was the combination of two metals (the iron in the fence and the copper wires holding the leg) that caused the frog to jump. When Italy’s premier electrician, Alessandro Volta, heard about it, he thought that it was the metal that electrified the frog (especially after he got two metals to make a live frog jump), and after spending a few years playing with it decided that it only worked when wet. In 1800, Volta proved his theory by making a pile of metals with wet cardboard between them that would give continual shocks. Volta gave his device an odd name (artificial electric torpedo) so most people called it a galvanic pile, or, sometimes, after Franklin’s term for Leyden jars, a battery. Volta published his paper in England as well as Italy and France and the secretary of the Royal Society of London let his friend Anthony Carlistle read it first, and when Carlistle and his friend made a pile, they accidentally found that the ends of the battery would bubble where one end was hydrogen and one was oxygen! Batteries could do more than shock, they could also electrically separate chemicals!
Volta’s discovery happened just weeks before a handsome Chemist and poet named Humphry Davy was given a lectureship at the newly made Royal Society of London. Davy then impressed everyone with his galvanic experiments and then proved that Volta’s pile worked due to chemistry as the water was salty, and therefore it would work better with a stronger acid, which it did, making Davy into a scientific superstar. (Davy was also an excellent speaker and the poet Samuel Coleridge said he went to his science lectures to, “increase my stock of metaphors”). Anyway, Davy heard that another scientist used a battery to make gold and silver foil glow and, in 1801, he also found that, “a thin slip of platinum” glows with “a vivid light[iii]”(which is why he is often credited with discovering incandescence). The next year, in Scotland, a surgeon named William Cruickshank was using a battery for biological experiments and found that his pile kept on falling down, so he placed the pile on its side called a trough battery. This gave Davy an idea to make a huge, giant, big battery with 2,000 plates of copper and zinc and gallons of acid in the basement of the Royal Institute, with wires to the lecture hall and laboratory (He kept it in the basement because it smelled really bad). In 1806 and 1807, Davy used his battery to increase the number of known elements by 62%! With this giant battery on November 16th, 1809, Davy demonstrated something that was amazing, see he had found that if he connected his battery to two carbon rods, the space between the rods would glow, very, very brightly, which was called an arc lamp possibly because the light would arc between the electrodes. An audience member wrote that the light, “was so intense as to resemble that of the sun … [it was] a dazzling splendor[iv]” Suddenly, the 100-year-old electric light bulb was powerful enough and long-lasting enough to be useful. Still, it took another 55 years for anyone to actually make money from this “arc-lamp” of Davy’s, and a further 20 years before Edison made a profit off of the incandescent lamp. Why did it take so long and how did this all occur? That’s next time on the lightning tamers.
Davy electrified a vacuum tube with a bit of mercury in it, Hauksbee style, (in what was called a Torricellian vacuum, as the barometer was invented by Torricelli),
Hired a bookbinder’s apprentice who had learned science from reading the books in the store and who desired, “to escape from trade, which I thought vicious and selfish, and to enter into the service of Science, which I imagined made its pursuers amiable and liberal”
Coleridge the poet said that he attended Davy’s lectures, “to increase my stock of metaphors”
[i] Heilbron, J. Electricity in the 17th and 18th Centuries (1979) p. 313
[ii] (pg 2 – Experiments). Franklin
[iii] Humphry Davy to Davies Giddy (Nov 14, 1801) Paris, J The Life of Sir Humphry Davy: Volume 1 (1831) P 87
[iv] Notes Philosophical Magazine of London vol. xxxv (Jan – June 1810) p. 463