Jul 29, 2020
Cosmos Recap: Finally, How The Motherf***ing Magnets Work
The title of this week’s Cosmos, “The Electric Boy,” isn’t a Spielberg movie. It just sounds like one. Our electric boy is Michael Faraday (1791-1867), who puzzled out electricity and magnetism. Without his discoveries, says Tyson, we might not be using electricity, watching TV and computing. Blame Faraday for Twitter and 19 Kids and Counting.
Unlike the thematic episodes, this one is pretty much straight biography, and mostly animation: we start with a very young Michael Faraday getting punished for not pronouncing his r’s correctly, and dropping out of school. By age 13 he was working in a book bindery and reading voraciously; at 21, he went to a lecture and demonstration on electricity by chemist and science popularize Humphry Davy at the Royal Institution, and was so taken by the topic that he bound his handwritten notes on Davy’s lecture into a book, which he presented to the great man (And Tyson, every bit the showman as Davy, lets us see the very book). Faraday’s gift made enough of an impression that Davy hired him as a secretary after temporarily blinding himself in an explosive experiment. And yes, I did find myself saying “The goggles, they do nothing!” We cut from a bloodied Davy screaming “My eyes! My eyes!” to an ad for the new Dodge Dart, another thing you should not stick in your eye.
After the break, Davy hires Faraday, who dreams of a life in science, since “men of science are amiable and morally superior.” Davy replies, “I take it I’m the first man of science you’ve ever met.” That is what you call the ironical foreshadowing! Faraday gets a full time job, and comes to live in an apartment at the Royal Institution with his blushing animated bride Sarah. One day, Davy poses a stumper for Faraday — why would an electrified wire near a compass cause the needle to move away, as if the wire were a magnet? What if you could get the magnetized needle to turn continuously? And how are electricity and magnetism related? Faraday gets mega-excited, and throws himself into designing an experiment that turns out to be the first electric motor, using a bowl of mercury, some stiff copper wire, and a magnet. Add current, and the wire’s resulting magnetic field made it circle the upright magnet. (There’s a nice updated version, using salt water instead of mercury, on the YouTubes) It doesn’t look like much, but as Tyson puts it, it was the first time anyone had put an “army of electrons at the command of human whim.” More practical, useful applications for electricity soon followed, of course, and Faraday became instantly famous and rich!
Haha, that is a joke! Because while Faraday did become well-known among sciencey types, Davy, living up to that foreshadowing from just minutes ago (and perhaps peeved that Faraday neglected to acknowledge Davy’s earlier work with him in his published results — a slight Tyson doesn’t mention but the wiki does), shunted him off into a fruitless attempt to discover the secrets of Bavarian optical glassmakers, who kept their secrets carefully hidden. If only Faraday could have seen episode 5, he’d have known that. Instead, he toiled for four years in a hopeless attempt to learn something about glass manufacturing, and eventually gave up, keeping only a block of glass that was of little use other than as a paperweight and as more foreshadowing.
Davy died in 1831, and Faraday became the director of the laboratory at the Royal Institution, where in 1825 he instituted a series of Christmas Day lectures for young people, which have continued up through the present. And there’s Carl Sagan with his mock-up of the Viking Mars lander in 1977, so we can all go “squee!” (as of course one does).
More animation, a recreation of Faraday’s Christmas lecture, showing off the wonders of electricity — including a “don’t try this at home” as he holds a wire in one hand and lights a gas jet using nothing but the electrons flowing from the fingertip of the other. And then, more inventions: the first generator, just a magnet moving between copper coils, moving those electrons.
And then in 1840, at the age of 49, Faraday had a mental breakdown, suffering memory loss and depression — he never quite recovered, but went on discovering. He conducted an experiment proving that an electromagnetic field could affect polarized light waves — Tyson acknowledges that “it’s hard to understand” and that we shouldn’t feel too terribly bad if we don’t grasp it, and so we will happily just refer you, Gentle Reader, to the wiki entry on the Faraday effect, and cut straight to the why-it-matters part: Faraday proved that light, electricity, and magnetism are all related — light can be bent by electromagnetism (longread explanation here). This is the sort of thing that got Einstein all hot and bothered years later. And as it happened, the substance Faraday used as a medium to help bend light with his electromagnet turned out to be that block of glass from his failed glassmaking years. (Cue Paul Harvey telling us that now we know the rest of the story.)
After a commercial, it’s time for Faraday’s discovery of magnetic fields, his recognition that the patterns made by iron filings around a magnet weren’t just pretty pictures, but revealed a patterns of magnetic force — and we get a brief tutorial on birds’ ability to sense the Earth’s magnetic field, which is generated by the layer of molten iron that surrounds its solid iron core. There’s a brief shout-out to the Van Allen belts, held in place by Earth’s magnetic field, and the fine job those charged particles do of shielding us from cosmic rays, which would otherwise, in scientific parlance, mess us up something fierce.
We also get some lovely time-lapse film of the Auroras, that light show caused by charged particles from the Sun — the solar wind — interacting with Earth’s magnetic fields. It’s nice, frankly, too see some photography for a change, instead of all that CGI and animation.
The week’s final segment looks at the boost Faraday’s ideas received when coupled with the mathematical genius of James Clerk Maxwell, who converted Faraday’s concepts into equations. (But first, there’s a short animation of Maxwell as a child, riding a tricycle through the halls of his parents’ mansion. It’s pretty much a gratuitous visual nod to The Shining, for no apparent reason.) In a nice parallel, we get a scene of Faraday opening Maxwell’s treatise, thinking back to his own gift to Davy. Tyson reminds us that in physics, an equation is just mathematical shorthand for something that can be represented in space and time — like the math showing that a pendulum can never swing higher than its original height. And Maxwell’s equations, turning Faraday’s observations into numbers, and in the process discovered that one part of the theory was inadequate — and realized that Faraday’s model of magnetic fields as static was wrong — rather than being fixed, they’re waves, spreading outward at the speed of light. That’s a good thing for electronic communication, although suddenly we reach the end of the episode before there’s enough time to go into exactly how all that works. But we get lovely images of people communicating at the speed of light, and that’s really the point anyway.
One thing that struck me as a bit odd — for all the talk of electricity and magnetism, there’s not a heck of a lot of discussion of electrons themselves in this episode. I was expecting a lot of CGI animation of the little boogers zapping around in a circuit, but for some reason, the producers chose to leave that particular visual model out. Seems an odd choice, but one that only feels like it’s missing because of all the other science films thrown at us throughout public school.
Also worth noting: This appears to be the only episode of Cosmos, so far, that the creationist loons at Answers in Genesis haven’t accused of being full of affronts to God’s Truth. Nice to know they’re good with electrons at least.
Cosmos: A Spacetime Odyssey airs on Fox 9:00 Sundays Eastern/Pacific, 8:00 Central/Mountain. Reruns Monday on National Geographic Channel 10:00 Eastern. Episode 10, “The Electric Boy,” online at CosmosOnTV.com