Wired Through Time — From Amber to Qubits

Rosa: Welcome to Wired Through Time, the Hard To Find Code history series. I'm Rosa Delgado, journeyman wireman.

Marcus: I'm Marcus Hale, city electrical inspector. Your friendly neighborhood AHJ.

Jaden: And I'm Jaden, second-year apprentice. I'm the one asking the questions.

Rosa: Good, because that's the job. Jaden, where does the word electric come from?

Jaden: Some guy named Electric?

Marcus: Close. It comes from amber. Rub a piece of amber and it picks up bits of straw. The Greek word for amber was elektron.

Rosa: The man who turned that party trick into science was William Gilbert, an English physician. In 1600 he published De Magnete. On the Magnet.

Jaden: So he was a magnet guy.

Rosa: Magnet guy first. He argued the whole Earth is one giant magnet, which is why a compass points north. But he also tested dozens of materials to see which ones attract the way rubbed amber does, and he coined a Latin word for them. Electricus. Like amber.

Marcus: Then in 1646 Sir Thomas Browne put the word electricity into English, built right on Gilbert's Latin.

Jaden: So before anybody made a spark on purpose, they had to name it.

Rosa: Exactly. And look at his method. He didn't trust old stories. He tested, wrote it down, and let other people check his work.

Marcus: Which is all an inspection really is. I'm not taking your word for it. I'm checking your install against a written standard anybody can verify. Gilbert would've made a decent inspector.

Jaden: So how did he tell electric from magnetic?

Rosa: A magnet only grabs iron. Rubbed amber grabs almost anything light. Paper, straw, hair. He figured they were two different forces. It took more than two centuries to prove they're two faces of the same thing.

Marcus: Hold that thought. That's episode four.

Jaden: Okay. Jobsite takeaway?

Rosa: Static isn't just history. A static discharge can still kill a circuit board or ignite fuel vapor. That's why we bond at fuel dispensers and why techs wear wrist straps.

Marcus: Timeline marker. 1600, De Magnete. 1646, the word electricity enters English.

Rosa: Next time, a glass jar that knocked grown men off their feet, and a kite over Philadelphia. I'm Rosa.

Marcus: Marcus.

Jaden: Jaden. Stay grounded.

Rosa: Wired Through Time. I'm Rosa, with Inspector Marcus and apprentice Jaden. Today, storing a spark.

Jaden: Like a battery?

Rosa: Closer to a capacitor. In 1745 a German cleric, Ewald von Kleist, and in 1746 a physics professor at Leiden, Pieter van Musschenbroek, each found you could store static charge in a glass jar of water with a conductor inside.

Marcus: Two people, working separately, same discovery. That happens a lot in this series.

Jaden: Why a jar?

Rosa: Glass is the insulator. Conductor inside, conductor outside, glass between. That's a capacitor. They called it the Leyden jar, and when you touched it, it let go all at once.

Marcus: Which is why I still tell crews, a de-energized circuit isn't a safe circuit until stored energy is discharged. Capacitor banks, drives, long cable runs. Verify before you touch.

Jaden: Okay, so where does Ben Franklin come in?

Rosa: Franklin was playing with Leyden jars in Philadelphia, and he suspected lightning was the same stuff, just enormous. His own description of the kite experiment ran in the Pennsylvania Gazette on October 19, 1752.

Jaden: The newspaper ran how-to instructions for flying a kite in a thunderstorm?

Marcus: They did. Silk kite, pointed wire on top, a key near your hand. He wrote that the electric fire would stream out plentifully from the key on the approach of your knuckle.

Rosa: And the key could charge a Leyden jar. That was the proof. Lightning and the spark in the jar were the same thing.

Jaden: Please tell me nobody does that today.

Rosa: Please don't. The practical win was the lightning rod. A pointed conductor up high, bonded down to earth, gives that strike a path that isn't your roof.

Marcus: That's still in play. Lightning protection has its own standard, NFPA 780, and the NEC requires that lightning protection system ground terminals be bonded to the building's grounding electrode system. Section 250.106.

Jaden: So Franklin's rod turned into a code section.

Rosa: Most of the code started as someone's bad day. Timeline marker, Marcus?

Marcus: 1745 to 1746, the Leyden jar. October 19, 1752, Franklin's kite account in the Pennsylvania Gazette.

Rosa: Next time, an Italian professor stacks metal discs and gets steady current. I'm Rosa.

Jaden: Jaden. Discharge before you touch.

Rosa: Wired Through Time. Rosa here, with Marcus and Jaden. Today, the first steady current.

Jaden: Up to now it's all sparks and jars.

Rosa: Right. A Leyden jar dumps everything at once. Nobody could get current to keep flowing. Then in 1800 Alessandro Volta, a professor at Pavia in Italy, wrote a letter to Sir Joseph Banks at the Royal Society in London.

Marcus: And the Royal Society published it in the Philosophical Transactions that same year. The title is a mouthful. On the Electricity Excited by the Mere Contact of Conducting Substances of Different Kinds.

Jaden: Different kinds of what?

Rosa: Metals. He stacked discs of two different metals with cardboard or cloth soaked in salt water between them. Metal, metal, wet layer, repeat. The taller the stack, the stronger the push.

Jaden: The voltaic pile.

Rosa: The first battery. And the unit on every meter you own, the volt, is named after him.

Marcus: Here's the part I want you to remember, Jaden. Volta proved that two different metals touching, with moisture around, make a voltage. On a jobsite we call that a problem.

Jaden: Galvanic corrosion.

Marcus: Right. Copper and aluminum in the same lug, with a little moisture, and you've built a tiny, slow battery that eats the connection. That's why NEC 110.14 says dissimilar conductors can't be intermixed in a terminal unless the device is identified for it.

Rosa: The AL-CU marking on a lug is Volta's ghost.

Jaden: So how did people use the pile?

Rosa: Within weeks, other scientists used it to split water into hydrogen and oxygen. Steady current opened up electrochemistry, and later, the telegraph.

Marcus: Code tie-in for storage, too. Batteries have their own article now, 480, and energy storage systems have 706. Ventilation, disconnects, working space. Volta's stack got a whole rulebook.

Jaden: Wild that it started with a letter.

Rosa: Peer-reviewed mail. Timeline marker?

Marcus: 1800. Volta's letter in Philosophical Transactions. The battery arrives.

Rosa: Next time, a Scottish woman gets published by the Royal Society, and Michael Faraday wraps wire around an iron ring. I'm Rosa.

Jaden: Jaden. Match your metals.

Rosa: Wired Through Time. Rosa, Marcus, Jaden. Today, three papers that tied electricity, magnetism, and light together.

Jaden: Episode one said they were two faces of the same thing.

Rosa: Here's the proof. Paper one, 1826. Mary Somerville, a self-taught Scottish mathematician, tests whether violet sunlight can magnetize a steel needle. Her paper is read to the Royal Society in February 1826 and published in the Philosophical Transactions.

Marcus: Communicated by her husband, because she couldn't present it herself. Historians describe it as the first paper by a woman to be read to the Royal Society and published in its journal.

Jaden: Did it work?

Rosa: Honestly, later experimenters couldn't reproduce the effect. But the question she asked, does light have something to do with magnetism, turned out to be exactly the right question.

Rosa: Paper two. August 29, 1831. Michael Faraday wraps two separate coils of wire around one iron ring. He switches a battery on and off in the first coil, and a current jumps in the second coil, which isn't connected to anything.

Jaden: Wait. That's a transformer.

Rosa: That's a transformer. And a moving magnet making current is a generator. Faraday published it in the Philosophical Transactions as the first series of his Experimental Researches in Electricity.

Marcus: Every pad mount, every dry type in an electrical room, every generator on a job. Article 450 exists because of that ring.

Jaden: And paper three?

Rosa: 1865. James Clerk Maxwell publishes A Dynamical Theory of the Electromagnetic Field, again in the Philosophical Transactions. He shows that light itself is an electromagnetic wave.

Rosa: So Somerville asked, Faraday demonstrated, Maxwell wrote the math.

Marcus: And every antenna, radio, and wireless meter reading goes back to Maxwell. Jobsite takeaway. Changing current makes fields, and fields induce voltage. That's why a de-energized conductor running next to a live one can still bite you.

Rosa: Timeline marker?

Marcus: 1826, Somerville. 1831, Faraday's ring. 1865, Maxwell's field theory.

Rosa: Next time, a cable across the Atlantic, a City Hall fire, and the women keeping the telegraph running. I'm Rosa.

Jaden: Jaden. Test before touch.

Rosa: Wired Through Time. Rosa, Marcus, Jaden. Today, the internet of 1858.

Jaden: The telegraph?

Rosa: The telegraph. And first, a name. Sarah Bagley, in Lowell, Massachusetts, is described as perhaps the first woman to work as a telegraph operator, in 1846. Women worked telegraph keys from the very beginning.

Marcus: Small-town stations needed operators, and women filled those seats for decades.

Jaden: So what happened in 1858?

Rosa: The Atlantic Telegraph Company laid a cable across the ocean floor. On August 16, 1858, Queen Victoria and President James Buchanan exchanged messages. Her greeting was ninety-eight words, and it took almost sixteen hours to get through.

Jaden: Sixteen hours? For a text?

Marcus: And people still went wild. On August 18, New York threw a celebration, and the fireworks set City Hall on fire. Harper's Weekly put the burning City Hall on its cover.

Rosa: Tiffany even sold souvenir pieces of leftover cable.

Jaden: So it was a hit.

Rosa: For a few weeks. The signals got weaker. The company's electrician, Wildman Whitehouse, decided the answer was more voltage, sometimes up to two thousand volts. The cable failed completely within weeks.

Marcus: An investigating commission blamed his high-voltage approach. Later analysis also pointed to poor manufacturing, an off-center copper core, and insulation that deteriorated after sitting in storage over the winter.

Jaden: So the celebration was selling something that was already dying.

Rosa: Marketing got ahead of the engineering. The cable that finally worked was laid in 1866.

Marcus: Jobsite lesson. Insulation has a voltage rating, and it has a storage life. Cable sitting out in the sun, water getting into reel ends. And when you do insulation resistance testing, you use the test voltage the manufacturer and the test standard call for, not whatever gets a reading.

Rosa: Whitehouse basically megged his own cable to death.

Jaden: That's going on my safety board.

Rosa: Timeline marker?

Marcus: 1846, Sarah Bagley at the key. August 1858, the first Atlantic cable, the City Hall fire, and the failure. 1866, a working cable.

Rosa: Next time, Edison flips a switch on Pearl Street, and a newspaper writes about the light. I'm Rosa.

Jaden: Jaden. Respect the rating.

Rosa: Wired Through Time. Rosa, Marcus, Jaden. Today, the first central power station.

Jaden: Edison.

Rosa: Edison. September 4, 1882, around three in the afternoon, Edison is at J.P. Morgan's offices and his new generating station at 257 Pearl Street in lower Manhattan starts supplying customers.

Marcus: The service area was called the First District. About a quarter of a square mile.

Jaden: How many customers?

Rosa: On opening day, about eighty-five customers and about four hundred lamps. The station was built around six steam-driven dynamos the crews called Jumbos. Twenty-seven tons each, around a hundred kilowatts apiece.

Marcus: And the distribution was underground. About eighty thousand feet of conductors under the streets. At a hundred and ten volts DC.

Jaden: Underground in 1882? That's a trench job.

Rosa: That's a huge trench job. And here's our newspaper source. The New York Times was one of the first customers, and on September 5 it wrote about its own office being lit.

Marcus: The Times said the light was soft, mellow, and grateful to the eye, and it seemed almost like writing by daylight, without a particle of flicker.

Jaden: That's a good review.

Rosa: The Times had skin in the game. But it tells you what people were comparing against. Gas light flickered, it was hot, and it gave you a headache.

Marcus: It also added risk. Now there's current running into buildings full of wood and fabric, and nobody's inspecting it yet. That problem gets its own episode.

Jaden: Why only a quarter square mile?

Rosa: Because it was low-voltage DC. The farther you push it, the more voltage you lose in the wire. So Edison's plan meant a power station every mile or so.

Marcus: Voltage drop. Same math you do today when the informational note in 210.19 suggests keeping branch circuit drop around three percent. It's not a hard requirement, but Edison lived and died by it.

Jaden: So the weakness of DC is distance.

Rosa: And somebody with a better idea for distance is coming. Timeline marker?

Marcus: September 4, 1882, Pearl Street begins service. September 5, the Times reviews its own lights.

Rosa: Next time, the War of the Currents turns ugly. I'm Rosa.

Jaden: Jaden. Watch your voltage drop.

Rosa: Wired Through Time. Rosa, Marcus, Jaden. Fair warning, this one gets dark.

Jaden: The War of the Currents.

Rosa: Right. May 16, 1888, Nikola Tesla gives a lecture to the American Institute of Electrical Engineers in New York. The title was A New System of Alternate Current Motors and Transformers.

Marcus: A conference talk. The peer-review channel of its day.

Rosa: Tesla lays out polyphase AC. With transformers, you can step voltage up to travel long distances and step it back down at the building. That solves Edison's distance problem.

Jaden: And George Westinghouse bets on it.

Rosa: He does. And the Edison side goes on the attack, pushing the idea that alternating current is the deadly one.

Marcus: Which leads to the electric chair. New York adopted electrocution as supposedly a humane replacement for hanging, and the chair used alternating current.

Jaden: That's a marketing campaign?

Rosa: A smear campaign. Tie your competitor's product to death. In March 1890, the New York Court of Appeals ruled the method wasn't cruel punishment. Then on August 6, 1890, William Kemmler was executed at Auburn Prison.

Marcus: And it went badly. The first current, around a thousand volts for seventeen seconds, didn't kill him. They had to apply it again.

Jaden: Oh no.

Rosa: The New York Times ran the story the next day under the headline Far Worse Than Hanging. Witnesses were described as sick and shaken.

Marcus: So as marketing, it failed twice. It wasn't humane, and it didn't stop AC. Alternating current still won the grid.

Jaden: What's the takeaway for us?

Marcus: Respect for what current does to a body. Today we have real research on that, which we'll get to in the GFCI episode. And the NEC draws a line at a thousand volts for a lot of requirements. Over a thousand volts, the rules change.

Rosa: And don't let marketing tell you what's safe. Test it, list it, and inspect it.

Jaden: Did Edison ever come around on AC?

Rosa: His company did. In 1892 it merged into the new General Electric, and GE built plenty of AC equipment. Timeline marker, Marcus?

Marcus: May 16, 1888, Tesla's AC lecture. August 6, 1890, the first electrocution. August 7, the Times: Far Worse Than Hanging.

Rosa: Next time, a World's Fair lit by AC, a young engineer who founds UL, and Niagara Falls. I'm Rosa.

Marcus: Marcus.

Jaden: Jaden. Respect the current.

Rosa: Wired Through Time. Rosa, Marcus, Jaden. Today, AC goes public.

Jaden: After the chair, I'd want some good press.

Rosa: They got it. In May 1892, Westinghouse won the bid to power and light the 1893 World's Columbian Exposition in Chicago. The White City.

Marcus: The fair's Palace of Electricity was lit by more than a hundred thousand incandescent bulbs.

Jaden: A hundred thousand bulbs in 1893. What about fire?

Rosa: That's the right question, and one young engineer asked it. William Henry Merrill was sent from Boston to Chicago to assess the fire risks at the fair.

Marcus: In 1894 he founded the Underwriters' Electrical Bureau, a bureau of the National Board of Fire Underwriters. We know it as Underwriters Laboratories. UL.

Jaden: The UL on the back of every device.

Marcus: That mark is why NEC 110.3 matters to me. Listed and labeled equipment has to be installed and used according to its listing and labeling instructions. If you ignore the instructions, you've voided the testing.

Rosa: So Merrill starts with fire insurance and ends up shaping every product we install.

Jaden: And Niagara?

Rosa: At midnight on November 16, 1896, power from the Niagara Falls generating plant was sent to Buffalo, New York, using alternating current. Westinghouse built the equipment on Tesla's system.

Marcus: Newspaper source. The trade paper Electrical Review ran it under the headline Niagara Falls Power in Buffalo. A successful test at midnight, with one thousand horsepower sent to the Buffalo Railway Company.

Jaden: So the first customer was a streetcar line.

Rosa: Streetcars were big early loads. Power made far away, sent miles down a line, and used somewhere else. That's the modern grid, right there.

Marcus: And it made a new problem. High voltage on long lines means clearances, insulators, and working distances. The rules for utility lines and for over a thousand volts in a building come out of that.

Rosa: Timeline marker?

Marcus: 1893, the White City. 1894, Merrill founds what becomes UL. November 16, 1896, Niagara powers Buffalo.

Rosa: Next time, five different electrical codes, twenty-three people in a room, and the first NEC. I'm Rosa.

Jaden: Jaden. Read the listing.

Rosa: Wired Through Time. Rosa, Marcus, Jaden. Today, the birth of the code book in your truck.

Jaden: The NEC. My backpack weighs ten pounds because of it.

Marcus: Blame 1896. By then there were five different, incompatible electrical codes in use across the country.

Rosa: Imagine wiring a building one way in one city and failing inspection in the next town over.

Jaden: So who fixed it?

Marcus: Francis B. Crocker, a Columbia engineering professor, organized a meeting. March 18 and 19, 1896, twenty-three people met in New York City.

Rosa: They formed the Underwriters' National Electrical Association, and in 1897 the first National Electrical Code was finished.

Jaden: And NFPA?

Marcus: NFPA took shape in 1896 too, but over fire sprinklers. Insurance people found nine different sprinkler standards in use within a hundred miles of Boston. In 1911, NFPA became the sponsor of the NEC.

Rosa: And now there's a new edition every three years through the consensus process. Anybody can submit a public input.

Jaden: Even me?

Marcus: Even you. That's the point of consensus. Contractors, inspectors, manufacturers, and utilities all at the table.

Rosa: Now the wiring they were writing rules for. Knob-and-tube. From about the 1880s to the 1930s, two separate conductors run apart from each other on porcelain knobs, with porcelain tubes through the framing.

Jaden: I've pulled that out of old houses. Cloth insulation.

Marcus: And it was designed to shed heat into open air. Bury it in blown-in insulation, overload it, splice onto it badly, and you've got trouble. Today, Article 394 still covers concealed knob-and-tube, but mostly for extending existing installations under special permission.

Rosa: Then came armored cable, the BX a lot of old-timers still call it, and later nonmetallic sheathed cable. Each wiring method got its own article.

Jaden: So every article in the code is like a chapter of this history.

Rosa: That's the whole reason we're doing this series. Timeline marker?

Marcus: 1896, five competing codes and a twenty-three-person meeting. 1897, the first NEC. 1911, NFPA takes over sponsorship.

Rosa: Next time, an episode about spectacular product flops. A talking doll and an electric corset. I'm Rosa.

Jaden: Jaden. Submit that public input.

Rosa: Wired Through Time. Rosa, Marcus, Jaden. Today, two great flops.

Jaden: I love a good flop.

Rosa: Flop number one. An 1883 ad for Dr. Scott's Electric Corset. A fashionable undergarment that promised a list of health benefits.

Jaden: An electric corset? Was it wired?

Marcus: Not really. Historians say the electric part was probably a magnet sewn into the lining. Strong enough to move a compass needle, but no actual electricity.

Rosa: In the 1880s, electric was the hot new word. Stick it on a product and it sells, whether there's any current involved or not.

Jaden: Like putting AI on everything now.

Rosa: No comment. Flop number two is Edison himself. In April 1890 the Edison talking doll hits the market. Twenty-two and a half inches tall, four pounds, with a tiny phonograph inside playing a twenty-second nursery rhyme.

Marcus: Ten dollars undressed, twenty dressed. Serious money in 1890.

Jaden: Who did the voices?

Rosa: That's our women-in-history angle. The recordings were done by young women and girls, reportedly as many as eighteen of them, reciting Mary Had a Little Lamb, Jack and Jill, and other rhymes, one doll at a time.

Marcus: Every cylinder was recorded individually. No mass duplication yet. That's a production nightmare.

Jaden: So what went wrong?

Rosa: Everything. The crank was hard to turn, the stylus and wax records wore out, and the sound was poor. By May 1890, Edison pulled it. An estimated twenty-five hundred shipped, and maybe fewer than five hundred sold.

Marcus: And Edison reportedly called them little monsters.

Jaden: One month on the market.

Rosa: Lesson from both. The label said more than the product could deliver. And nobody tested it the way a real customer would use it.

Marcus: That's my job in one sentence. NEC 110.2 says equipment has to be approved, meaning acceptable to the AHJ. A catchy label doesn't get you there. A listing from a testing lab usually does.

Rosa: Timeline marker?

Marcus: 1883, the electric corset ad. April to May 1890, Edison's talking doll launches and gets pulled.

Rosa: Next time, Hertha Ayrton figures out why arc lights hiss, and walks into a men-only institution. I'm Rosa.

Jaden: Jaden. Read past the label.

Rosa: Wired Through Time. Rosa, Marcus, Jaden. Today, one of my heroes. Hertha Ayrton.

Jaden: Never heard of her.

Rosa: That's why she gets an episode. In the late 1800s, streets were lit by electric arc lamps. Current jumps a gap between two carbon rods and makes a blinding light.

Marcus: Great light. But arcs flickered, hissed, and were unstable. A real problem for the utilities selling them.

Rosa: Hertha Ayrton started out helping her husband with his arc research in the early 1890s. Then she took the research over herself.

Jaden: So what was causing the hiss?

Rosa: In 1895 and 1896 she published a series of articles in the trade journal The Electrician. She traced the hissing to oxygen reacting with the carbon rods.

Marcus: That's root-cause analysis. Not just, it hisses, replace it. Why does it hiss?

Rosa: Then in 1899, her paper The Hissing of the Electric Arc was presented to the Institution of Electrical Engineers and published in its journal. A paper written by a woman was a first for that institution.

Jaden: And they let her in?

Rosa: That same year, 1899, she was elected the first female member of the IEE. It's now the IET.

Marcus: Picture that room. Every seat in the meeting filled by a man, and the person who solved their lighting problem is a woman.

Jaden: So what does an arc lamp have to do with me?

Marcus: Everything. The arc she studied on purpose is the arc you're trying to avoid. An arc flash is that same plasma, except it's in your panel and you're standing in front of it.

Rosa: That's why we have NFPA 70E, arc flash labels, and PPE categories. And on the branch circuit side, arc-fault circuit interrupters, AFCIs, under NEC 210.12, are built to detect the signature of an arcing fault before it starts a fire.

Jaden: So she studied the thing that's now on our warning labels.

Rosa: She understood arcs better than almost anyone of her time. Timeline marker?

Marcus: 1895 to 1896, her Electrician articles. 1899, her IEE paper and her election as the first woman member.

Rosa: Next time, we meet the electron, and the quantum shows up. I'm Rosa.

Jaden: Jaden. Respect the arc.

Rosa: Wired Through Time. Rosa, Marcus, Jaden. Today, the particle we actually push through wire.

Jaden: The electron.

Rosa: The electron. On April 30, 1897, J.J. Thomson at Cambridge announced that cathode rays, those glowing beams in vacuum tubes, were made of tiny negatively charged particles. He called them corpuscles.

Marcus: He published the full work in the Philosophical Magazine in October 1897, under the title Cathode Rays.

Jaden: Corpuscles. Glad that name didn't stick.

Rosa: Me too. The point is that current is a flow of something real, and way smaller than an atom.

Marcus: Then comes a woman with a very sensitive meter. Marie Curie.

Jaden: I thought she was radiation, not electricity.

Rosa: Both. Uranium rays were known to make air conduct electricity. Marie's assignment was to measure how strongly different materials ionized the air.

Marcus: She used an electrometer Pierre Curie and his brother Jacques had designed, with a piezoelectric quartz crystal that measured incredibly small currents.

Rosa: So she made electrical measurements to rank how radioactive samples were. Good instruments led her to new elements.

Jaden: So a meter got her a Nobel Prize.

Marcus: Two Nobels, eventually. And it's a reminder that your meter is only as good as its rating and calibration. Use a meter with the right category rating for where you're working, and verify it works on a known source before and after.

Rosa: Then, December 14, 1900. Max Planck presents his derivation of black-body radiation to the German Physical Society in Berlin. To make the math work, he assumed energy comes in little packets. Quanta.

Jaden: So that's the birth of quantum?

Rosa: Many physicists date it right there. He treated it as a math trick. Five years later Einstein takes it seriously, and that's the solar episode.

Jaden: So where does Planck show up on a jobsite?

Marcus: Every LED, every solar cell, every transistor we cover later works because energy comes in those packets. Planck's math trick is inside half the equipment on a modern job.

Marcus: Timeline marker. 1897, Thomson's electron. 1898, the Curies' electrometer measurements. December 14, 1900, Planck's quanta.

Rosa: Next time, light turns into current. From a teenager in Paris to a rooftop in New York. I'm Rosa.

Jaden: Jaden. Live, dead, live.

Rosa: Wired Through Time. Rosa, Marcus, Jaden. Today, the prehistory of every PV system we install.

Jaden: Finally, solar.

Rosa: Start in 1839. Edmond Becquerel, nineteen years old, working in his father's lab in Paris, finds that light shining on certain materials produces an electric current. The photovoltaic effect.

Jaden: Nineteen?

Rosa: Nineteen. Then in 1883, a New York inventor named Charles Fritts coats selenium with a thin layer of gold and makes a working solar cell. By 1884 he'd put panels on a New York City rooftop.

Marcus: Efficiency was terrible, well under one percent. But it was a rooftop array a hundred and forty years ago.

Jaden: So why did it work at all?

Rosa: Nobody could really explain it until 1905, when Einstein, building on Planck, said light itself comes in packets. One packet can knock one electron loose. That's the photoelectric effect.

Marcus: And that's what his 1921 Nobel Prize was for. Not relativity. The law of the photoelectric effect.

Rosa: Now a woman. Mária Telkes, a Hungarian-American scientist her colleagues called the Sun Queen. In 1948 she helped create the Dover Sun House in Massachusetts, described as the first successfully solar-heated modern home.

Marcus: That was solar thermal, storing heat in chemical salts. But it proved people would live in a sun-powered house.

Rosa: Then Bell Labs, 1954. A silicon solar cell with useful efficiency. The New York Times put it on the front page on April 26, 1954, about the vast power of the sun being harnessed by a battery using a sand ingredient.

Jaden: Sand. Silicon. Nice.

Marcus: And now it's my inspection list. NEC Article 690 covers PV systems. Rapid shutdown under 690.12, so firefighters aren't standing on energized arrays. Disconnects, labeling, conductor sizing for high DC current.

Rosa: From one teenager's experiment to a whole code article.

Rosa: Timeline marker?

Marcus: 1839, Becquerel. 1883 to 1884, Fritts's rooftop. 1905, Einstein. 1948, Telkes's Dover Sun House. April 1954, Bell Labs makes the front page.

Rosa: Next time, electric cars sold as ladies' cars, and a car that got crushed. I'm Rosa.

Jaden: Jaden. Label your rapid shutdown.

Rosa: Wired Through Time. Rosa, Marcus, Jaden. Today, the electric car. Twice.

Jaden: Twice?

Rosa: Round one, the early 1900s. Electric cars started instantly, no hand crank, and they ran clean and quiet. Advertisers called them elegant, comfortable, and easy to operate, and they aimed them squarely at well-to-do women.

Marcus: Baker Electric ads in 1910 called their cars The Aristocrats of Motordom.

Jaden: So was that good marketing or bad marketing?

Rosa: Both. It sold cars. Clara Ford, Henry Ford's wife, drove a 1914 Detroit Electric. The Detroit Electric company built about thirteen thousand cars between 1907 and 1939.

Marcus: First Ladies rode in a Baker Electric at the White House from 1912 into the late 1920s.

Rosa: But labeling it a ladies' car boxed it into a niche. When gas cars got electric starters and cheap fuel, the electric looked like a luxury toy. That's my read, anyway.

Jaden: And round two?

Rosa: General Motors, the EV1. Built from 1996 to 1999, and only leased, never sold, to drivers in California and Arizona.

Marcus: When the program ended, GM took them back and crushed most of them. Drivers who loved the car couldn't buy it.

Jaden: That's a strange way to end a product.

Rosa: Two failures, two lessons. Market to one narrow group and you cap your own growth. And if you never let customers own it, they can't fight for it.

Marcus: Now the code side, because the EV came back for real. Article 625 covers electric vehicle power transfer systems. Chargers, cord sets, ventilation. And load calculations matter, because a charger is a big continuous load.

Jaden: Continuous load. One twenty-five percent sizing.

Marcus: Good. And on existing services, energy management systems under Article 750 can let you add chargers without a service upgrade.

Rosa: The early electrics would've loved a Level 2 charger in the carriage house. Timeline marker?

Marcus: 1907 to 1939, Detroit Electric. 1910, the Aristocrats of Motordom ads. 1996 to 1999, the EV1 is built. Most get crushed after leases end.

Rosa: Next time, Edith Clarke, the woman who did the math for the power grid. I'm Rosa.

Jaden: Jaden. Size for continuous load.

Rosa: Wired Through Time. Rosa, Marcus, Jaden. Today, the woman who did the math that keeps the grid stable. Edith Clarke.

Jaden: Another one I never heard of.

Rosa: Born in Maryland in 1883. Graduated from Vassar in 1908 in math and astronomy. In 1912 she became a computer at AT&T.

Jaden: A computer?

Marcus: Back then a computer was a person. Someone who did long calculations by hand for engineers.

Rosa: She studied electrical engineering at night, then went to MIT. In 1919 she became the first woman to earn a master's degree in electrical engineering there.

Jaden: So then she got an engineering job.

Rosa: Not right away. She had trouble getting hired as an engineer, so she took a job at General Electric supervising the computers.

Marcus: And while she was doing that, she invented something. In 1921 she filed a patent for a graphical calculator, the Clarke calculator, granted in 1925. It solved equations for long electric power transmission lines far faster than doing them by hand.

Rosa: In 1922, GE made her an electrical engineer, which made her the first professionally employed female electrical engineer in the United States.

Jaden: What was she actually calculating?

Rosa: Power system stability. When a fault happens or a big load switches, will the grid ride through it or collapse? In 1943 she published a textbook, Circuit Analysis of A-C Power Systems.

Marcus: And in 1947 she joined the University of Texas at Austin, the first female professor of electrical engineering in the country.

Jaden: And now she's in the Inventors Hall of Fame?

Rosa: She is. And the tools she built fed the methods utilities still use for system studies.

Marcus: Jobsite version. When you do a fault current calculation for a service, or coordination so the right breaker trips first, you're doing a small piece of Edith Clarke's work. NEC 110.24 even requires the available fault current marked at service equipment in most buildings.

Jaden: So that sticker on the switchboard traces back to her.

Rosa: Her kind of math, anyway. Timeline marker?

Marcus: 1919, first woman with an MIT master's in EE. 1925, Clarke calculator patent granted. 1947, first female EE professor in the U.S.

Rosa: Next time, farm lines, an association for women, and the invention that saves lives in bathrooms. I'm Rosa.

Jaden: Jaden. Mark your fault current.

Rosa: Wired Through Time. Rosa, Marcus, Jaden. Today, electricity comes home, and gets safer.

Jaden: Starting where?

Rosa: England, 1924. Caroline Haslett, an electrical engineer, becomes the first director of the Electrical Association for Women, which she co-founded. Its goal was to promote the benefits of electricity in the home.

Marcus: Women were running the households, so the association taught women how to use and choose electric appliances. That was smart.

Rosa: Now America. In 1934, only about eleven percent of U.S. farms had electric power.

Jaden: Eleven percent? In the thirties?

Marcus: Utilities didn't want to run miles of line for a few customers. So on May 11, 1935, President Roosevelt created the Rural Electrification Administration, the REA.

Rosa: It made loans to build lines to rural areas. By 1950, more than ninety percent of farms had power.

Jaden: That's a massive line construction job.

Rosa: Huge. And more electricity in kitchens, bathrooms, and yards meant more people getting shocked around water. Enter Charles Dalziel, an engineering professor at UC Berkeley.

Marcus: He studied what current does to the human body. His research found the let-go threshold, the current where you can't release a conductor, averaged about sixteen milliamps for men and about ten and a half for women.

Jaden: So that's where the numbers come from.

Rosa: Right. He's credited as the father of the ground-fault circuit interrupter. A GFCI compares the current going out and coming back. If some is leaking through a person, it trips.

Marcus: A Class A GFCI trips at around six milliamps. Code history, and this is my favorite list. 1968, the NEC introduces GFCI for underwater pool lights. 1971, receptacles near pools, construction sites, and outdoors. 1975, bathrooms. 1978, garages. 1987, kitchen receptacles near sinks.

Jaden: So every GFCI I install is from somebody's tragedy.

Rosa: And today 210.8 keeps growing every cycle. Timeline marker?

Marcus: 1924, Haslett's Electrical Association for Women. May 11, 1935, the REA. 1961, Dalziel's shock research paper. 1968 onward, GFCI in the NEC.

Rosa: Next time, the transistor gets buried on page forty-six, and a movie star patents frequency hopping. I'm Rosa.

Jaden: Jaden. Push the test button.

Rosa: Wired Through Time. Rosa, Marcus, Jaden. Today, the quantum device inside everything. The transistor.

Jaden: Why is a transistor quantum?

Rosa: Because you can't explain it without quantum mechanics. In 1928, Felix Bloch, Heisenberg's first doctoral student, wrote his thesis on the quantum mechanics of electrons in crystal lattices.

Marcus: That work helped lay the groundwork for band theory. Why copper conducts, why glass doesn't, and why some materials sit in between.

Jaden: Semiconductors.

Rosa: Semiconductors. Now a detour, and a great story. In 1942, the actress Hedy Lamarr and the composer George Antheil were granted U.S. Patent 2,292,387, for a secret communication system.

Jaden: A movie star has a patent?

Marcus: She was an inventor. The idea was frequency hopping. The transmitter and receiver jump between frequencies in sync, so an enemy can't jam the signal.

Rosa: It was meant to guide torpedoes. Spread-spectrum ideas like it now show up in wireless technology. She was inducted into the National Inventors Hall of Fame in 2014.

Jaden: Okay, the transistor.

Rosa: Bell Labs, late 1947. A working transistor. On June 30, 1948, Bell Labs announced it at a press conference.

Marcus: And our newspaper source. The New York Times gave it a few paragraphs on page forty-six, in a column called The News of Radio.

Jaden: Page forty-six? For the transistor?

Rosa: One of the great underestimated stories of the century. Nobody knew they were looking at the future.

Marcus: Today it's everywhere I inspect. Electronic trip units in breakers, AFCIs, GFCIs, inverters, drives, smart meters. All solid-state.

Jaden: And all of it is sensitive to surges.

Marcus: Right, which is why surge protection keeps expanding in the code. Article 242 covers surge protective devices, and dwelling services now need one under 230.67.

Rosa: Timeline marker?

Marcus: 1928, Bloch's thesis. August 1942, the Lamarr and Antheil patent. June 30, 1948, the transistor announcement. July 1, page forty-six.

Rosa: Next time, the first laser gets called a death ray, and a GE scientist makes glass disappear. I'm Rosa.

Jaden: Jaden. Protect the electronics.

Rosa: Wired Through Time. Rosa, Marcus, Jaden. Today, quantum light.

Jaden: Lasers and LEDs?

Rosa: Both. They trace back to 1916, when Einstein worked out the theory of stimulated emission. Hit an excited atom with the right light and it releases matching light.

Marcus: Theory in 1916. Hardware in 1960.

Rosa: May 16, 1960. Theodore Maiman at Hughes Research Laboratories fires the first working laser, a ruby crystal. Then on July 7, 1960, there's a press conference.

Jaden: Let me guess. Bad headline.

Marcus: Headlines like L.A. Man Builds Death Ray. It was a scientific instrument, and the press sold it as a weapon.

Rosa: A marketing lesson in reverse. The inventor didn't control the story. Now, a woman. Katharine Burr Blodgett, the first female scientist hired by General Electric's research laboratory, back in 1917.

Jaden: What did she invent?

Rosa: In 1938, invisible or nonreflective glass. She built up coatings a single molecule thick, until reflected light waves cancelled each other out.

Marcus: Thin films. The same idea is in the anti-reflective coating on camera lenses and eyeglasses, and a similar idea helps solar glass let more light in.

Rosa: Now LEDs. October 1962, Nick Holonyak Jr. and colleagues at General Electric demonstrate the first practical visible light-emitting diode. Red light, reported in Applied Physics Letters.

Jaden: But not white?

Rosa: White needs blue, and blue was brutally hard. In 2014, the Nobel Prize in Physics went to Isamu Akasaki, Hiroshi Amano, and Shuji Nakamura for efficient blue LEDs, which made bright, energy-saving white light possible.

Marcus: And that's half my lighting inspections now. LED retrofits in existing fixtures. Use a retrofit kit that's listed for the job, follow its instructions, and mark the fixture as modified.

Rosa: Timeline marker?

Marcus: 1916, stimulated emission. 1938, Blodgett's glass. 1960, the laser and the death ray headlines. 1962, the visible LED. 2014, the blue LED Nobel.

Rosa: Next time, zero resistance, the Woodstock of Physics, and a hype cycle. I'm Rosa.

Jaden: Jaden. Use listed retrofit kits.

Rosa: Wired Through Time. Rosa, Marcus, Jaden. Today, the dream of every electrician. A wire with no resistance.

Jaden: No voltage drop?

Rosa: None. April 8, 1911, in Leiden, Heike Kamerlingh Onnes and his team cool mercury with liquid helium, and its electrical resistance disappears. In a notebook, he wrote, mercury practically zero.

Marcus: Superconductivity. The catch was the temperature. A few degrees above absolute zero.

Jaden: So not in my conduit.

Rosa: Not in your conduit. For decades it was a lab effect. The quantum explanation came much later. Then in 1986 and 1987, researchers found ceramics that superconduct at much higher temperatures.

Marcus: Still very cold, but you could cool them with liquid nitrogen, which is cheap. Physicists lost their minds.

Rosa: March 18, 1987, the American Physical Society meeting in New York. A marathon session with fifty-one presentations, and the press nicknamed it the Woodstock of Physics. Reporters followed physicists around the city.

Jaden: So were there power lines with no resistance by the nineties?

Rosa: That's the hype part. Some demonstration cables and magnets, yes. But brittle ceramics and cooling costs slowed everything down. The headlines ran way ahead of the construction.

Marcus: And then 2023. On July 23, two preprints claimed a material called LK-99 superconducted at room temperature and normal pressure.

Jaden: I remember that. Videos of little rocks floating.

Rosa: Social media went wild. But labs tried to replicate it, and the consensus was that it had no zero-resistance state. And that November, the journal Nature retracted a different room-temperature superconductor paper.

Marcus: So preprint isn't peer review, and peer review isn't replication. Same as my world. The manufacturer's brochure isn't a listing, and a listing isn't a field test.

Jaden: Where do real superconductors show up now?

Rosa: MRI magnets are the big one. And they're about to matter a lot in our last episode.

Marcus: Timeline marker. April 8, 1911, Onnes. March 18, 1987, the Woodstock of Physics. July 2023, LK-99 and the hype cycle.

Rosa: Next time, the finale. A Nobel Prize for quantum physics you can build on a chip, and we come full circle to amber. I'm Rosa.

Jaden: Jaden. Wait for replication.

Rosa: Wired Through Time. Rosa, Marcus, Jaden. Our last episode. Quantum mechanics you can build.

Jaden: I thought quantum was only for tiny particles.

Rosa: That's what most people thought. In 1984 and 1985, at UC Berkeley, John Clarke, Michel Devoret, and John Martinis built an electric circuit out of superconductors, separated by a very thin insulating layer.

Marcus: And they showed the whole circuit behaving like a single quantum object. It could tunnel through an energy barrier it shouldn't have been able to cross, and it absorbed energy only in fixed steps.

Jaden: A whole circuit? Big enough to hold?

Rosa: Big enough to see on a chip. In October 2025 they were awarded the Nobel Prize in Physics for the discovery of macroscopic quantum mechanical tunnelling and energy quantisation in an electric circuit.

Marcus: And Martinis later used those fixed energy steps as quantum bits. Lowest state is zero, next step up is one. That's a qubit, the basic building block of a superconducting quantum computer.

Jaden: So Onnes's frozen mercury ends up in quantum computers.

Rosa: Exactly. Now our last woman of the series. Mildred Dresselhaus, called the Queen of Carbon Science. She spent decades on the electrical and thermal properties of carbon and helped lay the foundation for carbon nanotechnology. Graphite, nanotubes, and materials just one atom thick.

Rosa: Let's run it back. Rubbed amber and a Latin word in 1600. A jar that bit back. Volta's stack. Somerville's question, Faraday's ring, Maxwell's math. A cable that cooked, a street that lit up, a chair that shamed an industry.

Marcus: Then the code. UL, twenty-three people in a room, knob-and-tube, GFCIs. Every rule is somebody's hard lesson.

Jaden: And Ayrton's arcs, Curie's meter, Clarke's calculator, Telkes's sun house, Lamarr's patent, Blodgett's glass.

Rosa: Right up to a Nobel for quantum behavior in an electric circuit. Same electrons Gilbert was pulling off amber. We just learned to count them.

Marcus: And my final inspector note. The physics keeps getting stranger, but my checklist doesn't. Is it listed, is it installed per instructions, is it grounded and bonded, and did you verify it's de-energized?

Jaden: Test before touch.

Rosa: That's Wired Through Time. Sources for every episode are at hardtofindcode.com. I'm Rosa Delgado.

Marcus: Marcus Hale.

Jaden: Jaden. Stay grounded, everybody.