Electricity is basically subatomic particles being either attracted to or repulsed from each other, depending on whether they have a positive or negative charge. What's a positive/negative charge? All about how many positively charged protons there are versus negatively charged electrons. In each atom. If the atoms happen to be metal atoms in the shape of a wire, a change in negative/positive charge sends electrons all along the wire. That wire can be fed to a light bulb. Or a computer. But what starts the process of repulsing or attracting electrons?
Magnets. And Faraday figured it out. Born in 1791 in a tenement in what was then a suburb of London, he left school early due to a speech impediment, and never returned. He eventually was apprenticed to a local bookbinder, where he could spend nights reading the books he literally made during the day. He discovered an interest in scientific books. Working at a bookbinder had its perks: he received tickets, from a friend he met through work, to lectures at the Royal Institution, given by the Royal Society. Covered before, in the episode on Isaac Newton and Edmond Halley (episode 3) , the Royal Society was Britain's collection of the most eminent scientists.
It included Humphry Davy, a man who had already discovered calcium and sodium, who liked to enliven his lectures on chemistry and electricity. Back then, electricity was produced with chemical batteries. Basically, buckets of positively charged or negatively charged fluids connected by a conductive substance, so electrons can flow between them. Over time, the chemicals transfer enough material (positively or negatively charged) so that the buckets have an even distribution of electrical charge. Then the transfers stop, the power runs down, and you have to go get another battery. Humphry Davy would use a basement of huge chemical batteries to power the show at his lectures, all so he could demonstrate a small light of electric arc current between two wires. London was spellbound. Faraday took notes.
Faraday, using his skills as a book binder, literally turned his notes into a book on Davy's lectures, and impressed him enough to hire Faraday as a temporary assistant when Davy injured his own eyes in a chemical experiment. Faraday was so useful, Davy kept him on. Faraday excelled at experiments to solve problems. When William Wollaston and Davy couldn't figure out how to get an electrically charged wire to spin a magnet, Faraday went to work and built what is now called a homopolar motor: a wire, extended into a pool of mercury that already had a magnet in the center. If the magnet received an electrical charge, the wire would start to stir the mercury around the magnet, stirring the mercury in an unending circle for as long as the battery could charge the magnet. Faraday created the world's first motor. Every motor is essentially this, converting an electrical charge into some sort of circular motion that then drives another machine.
Build your own!
When Faraday published his work, Davy was furious for not getting the recognition he felt he deserved. Davy punished/buried Faraday, by assigning him the task of making optical glass that could compete with Bavaria's (episode 5). Faraday spent four years failing at this, until Davy died. Four years of effort, and all Faraday had to show for it was a glass block of a failed optical glass recipe. He kept it as a souvenir of his fruitless efforts.
After returning to the Royal Society's good graces in the 1820s, Faraday spent most of the rest of his career experimenting with the relationship between magnets, electric charges, and even light. Faraday discovered that if he set up a spiral wire, and move a magnet in the center of the spiral, that creates an electrical charge. In other words, Faraday created an electrcomagnetic generator.
Ta Da!
So, not only did Faraday discover that electricity could produce movement, but that movement (of a magnet) can produce electricity. The two (electricity and magnetism) were even more linked than previously thought. Most of what we do now is figure out new ways to create some sort of movement with a charged material that produces electricity. It's usually a turbine, which is any rotatable device, that has to be turned. It can be turned with pressure from steam, gas, or water. Producing the steam or gas is where fossil fuels have come in (from episode 9).
But Faraday wasn't done. Despite memory problems that brought on bouts of depression, he decided to see whether light waves were effected by magnets. By setting up a lantern with a mirror, he reflected candlelight through just about any chemical he wanted, set on top of a horseshoe magnet. Reflecting the light off a mirror transformed the light (which scientists already described as a wave) waves from diffuse rays going everywhere to specific rays in one direction, which is polarized light. This light then traveled into a lens (a Nicol eyepiece) from which Faraday could examine the light. This meant that not only did light pass through a transparent chemical, so did a magnetic charge.
Faraday creating polarized light
But that's not all. When Faraday took down his useless glass block sample from his souvenir shelf, he found that when light passed through the glass block when the magnet was charged from a battery, he got a perfect light wave through the Nicol eye-piece. As long as the eyepiece faced him. When it didn't, the light wave disappeared. In other words, Faraday had discovered how to make oscillations of light waves. We call it the Faraday Effect. In other words, Faraday invented the signal that would one day be used for all telecommunications. The magnetic charges had to be parallel to the direction of the light, leading Faraday to conclude that magnetic charges were really invisible lines.
The idea of magnetic charges as lines was as revolutionary as the technology that would later make cellphones possible. No one at the time believed him, mostly because these lines are invisible to humans. But we can know they exist for several reasons. One, birds can detect them naturally, using them to differentiate between North and South for migration. Two, birds can also detect, naturally, variations in these lines of magnetic force, and use those variations in place-finding, which is how carrier pigeons were used as communication devices until we had phones. Three, that's how your compass works. The magnetic pole doesn't "point north", it literally aligns itself with the lines of magnetic force that connect Earth's Poles. This is because the middle of our planet is liquid iron. That moves. And what do we know about moving, negatively charged materials? Why, they create magnetic fields.
Yes, we are surrounded by invisible circles.
Faraday eventually had help. A man from a totally different background, raised by wealthy, doting parents as an only child, James Clerk Maxwell was determined to prove mathematically, what Faraday could only infer from experiments. Using 20 variables and 20 equations, Maxwell used math to describe Faraday's lines of magnetic forces. It was Maxwell, solving electromagnetism with math, who realized electricity and electromagnetic waves move at the speed of light, which is why we perceive it to be instantaneous. Or, in the case of your satellite phone conversations, almost instantaneous. The waves have to travel, literally, thousands of miles. So, be patient.
Faraday, raised poor with almost no formal education, wasn't done innovating. In 1825, while working for the Royal Society, he started a yearly tradition that continues to this day: The Royal Society's Christmas Lecture, a showcase of the Royal Society and science worldwide. Faraday gave many of the early ones, until his death in 1867. But the tradition lives on, with lectures by John Tyndall, David Attenborough, Carl Sagan, Richard Dawkins, Susan Greenfield, and Bruce Hood. They lecture on their areas of expertise, from sound to light to biology to the search for other worlds. And the kids get up close and personal.
Tyson ends with our world's oldest and best light show: the Auroras over both the North and South poles. Our sun emits more particles than just light protons. These particles carry their own positive or negative charges, and hit the Earth's magnetic lines of force, where they ride the line to either Pole and release their energy as light photons. How fitting that Earth's best show combines light, magnetism, and electrically charged particles to demonstrate one of Faraday's most famous quotes:
"Nothing is too wonderful to be true, if it be consistent with the laws of Nature."
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