Sunday, April 5, 2026

Discovered by mistake

 

10 Great Innovations That Were Discovered by Mistake

From cornflakes to the pacemaker, some of our most beloved—and useful—products were born of blunders

 ET

Illustration of a yellow lightbulb emerging from a bullet casing.
Matt Chase for WSJ

“USA250: The Story of the World’s Greatest Economy” is a yearlong WSJ series examining America’s first 250 years. Read more about it from Editor in Chief Emma Tucker.

Mistakes are in the DNA of the U.S.A.: Christopher Columbus was trying to find a westward route from Europe to Asia when he discovered the New World.

Since then, the U.S. has repeatedly proved itself to be the land of luck. Harnessing happenstance has led to inventions that have changed the world—from extending the lives of cardiac patients to overhauling how humans eat. It even gave bored fingers little air bubbles to pop.

“People underestimate how improbable the improbable is,” says Christian Busch, a University of Southern California business-school professor and the author of “The Serendipity Mindset.”

Call it what you will: chances, providence, fluke, good fortune. For 250 years, it hasn’t been Archimedes in a bathtub, but tinkerers in workshops and scientists in labs, embracing—and capitalizing on—their blunders.

Here are 10 U.S. innovations born of mistakes:


Cornflakes

Vintage advertising for Kellogg's Corn Flakes showing a box of cereal, a bowl of cereal with bananas, a pitcher of milk and two bananas.
Who would have thought that a wheatberry-cooking experiment would change the trajectory of breakfast? Popperfoto/Getty Images

The Battle Creek Sanitarium, a world-renowned health spa in the eponymous Michigan city, drew fans of what today we’d call wellness culture. Dr. John Harvey Kellogg oversaw the facility, which preached exercise, fresh air and eating a healthy diet, which included dried and crumbled grains.

Kellogg and his younger brother, W.K. Kellogg, were experimenting with various ways to cook wheatberries. In 1894, the pair accidentally left a pot of boiled wheat to stand, and it dried out. When W.K. returned, he put the wheat through rollers. Each berry came out as a single large, flat flake that crisped when baked. 

The junior Kellogg later applied that to corn—and changed breakfast forever. In 1906, he launched the Battle Creek Toasted Corn Flake Co.; today you know it as the cereal giant Kellogg.


Implantable pacemaker

Black-and-white photo of Wilson Greatbatch with pacemaker batteries.
Wilson Greatbatch with pacemaker batteries. Division of Rare and Manuscript Collections/Cornell University Library

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Wilson Greatbatch saved millions of lives—without ever going to medical school. Once in the late 1950s, while building machinery to record sounds a heart makes, he accidentally used the wrong resistor, but its electrical pulse rate was steady, like a heartbeat.

“I stared at the thing in disbelief and then realized that this was exactly what was needed to drive a heart,” Greatbach wrote in his book “The Making of the Pacemaker.”

At the time, pacemakers existed but were external and huge. Previous ones had to be hand-cranked. His lightbulb moment? Put tiny versions into cardiac patients to regulate heartbeats. The first wholly implantable pacemaker was placed in a dog in 1958 and in a human two years later. 


Microwave

Black-and-white photo of Jackie Copeland demonstrating the Raytheon Radarange’s hamburger cooking abilities.
Jackie Copeland demonstrates the Raytheon Radarange's hamburger cooking abilities in 1946. Bettmann Archive/Getty Images

Maybe Percy Spencer was hungry. Shortly after World War II had ended, the Raytheon engineer had a candy bar in his pocket when he approached a magnetron—and realized his sweet treat was melting. He had discovered that electromagnetic energy could be used to heat food quickly. He tested it on popcorn and eggs.

Early models of what Raytheon called the Radarange were too large and pricey for at-home use. In 1967, a household countertop microwave made its debut; it cost less than $500. The following decade, food manufacturers expanded their product lines to include more microwavable dinners and snacks. Today, almost all U.S. households have at least one microwave, according to the most recent federal data.


Bubble Wrap

Rohn Shellenberger holding up a large sheet of Bubble Wrap.
Sealed Air’s Rohn Shellenberger talks about Bubble Wrap at the company’s plant in Saddle Brook, N.J., in 2010. Christopher Barth/AP

In 1957, Alfred W. Fielding and Marc Chavannes were trying to create a new kind of textured wallpaper by attaching two plastic sheets together, but pockets of air got stuck in between. The textured wall covering wasn’t a hit, but after bit of a do-si-do, they hit on cushioning for packages.

As years went by, the company Fielding and Chavannes founded expanded its wrap options to include a variety of bubble sizes. For those who really love popping the little buggers, you can say a word of thanks to the lucky inventors on Bubble Wrap Appreciation Day on the last Monday of January.


Vulcanized rubber

Black-and-white photo of workers stripping a tire from its mold in a factory in Akron, Ohio.
Workers stripping a tire from its mold in Akron, Ohio, around 1920-30. Gamma-Keystone/Getty Images

Rubber was popular in the early 19th century because it was waterproof and flexible. One problem, though: Untreated rubber becomes brittle when exposed to cold, and tacky and runny when hot. That limited its usefulness in the U.S.—and became Charles Goodyear’s obsession.

In 1839, after years of trying, he cracked the code for the uncrackable after rubber he had treated with sulfur somehow came in contact with a hot stove. When Goodyear examined the sample, he was stunned: Instead of melting, it became sturdy and durable without losing its flexibility and elasticity. Applying heat was counterintuitive, explained Charles Slack, author of “Noble Obsession: Charles Goodyear, Thomas Hancock, and the Race to Unlock the Greatest Industrial Secret of the Nineteenth Century.” The term “vulcanization” comes from Vulcan, the Roman god of fire.


Popsicles

Illustration of a Popsicle advertisement for 5 cents, with the slogan "A drink on a stick."
An 11-year-old’s invention. National Archives

Frank Epperson accidentally hit upon his innovation at the ripe old age of 11. In 1905, after a long day of playing, he left a stirrer in his cup of soda outside overnight. The next morning, with a quick flip upside down, Epperson had a sweet icicle with a built-in handle, which he dubbed the Epsicle.

His friends loved his portmanteaued frozen confection, which he patented in 1924. Epperson later changed the name, at his children’s suggestion, to a Pop’s ‘Sicle, or Popsicle. Later that decade, he sold his rights to Joe Lowe Co., which started to offer a two-stick version during the Great Depression. Popsicle passed through various corporate hands over the decades; Magnum Ice Cream, a Unilever spinoff, now owns it.


Saran Wrap

Packages of Saran Wrap on a grocery store shelf.
From a quirk at Dow Chemical to every kitchen. Alamy

Ralph Wiley was a Dow Chemical scientist for decades, but at the time of his best-known discovery, he was just a college student working there. One day in 1933, he and a colleague noticed that a dry-cleaning agent they were working with had turned the flask white. Researchers wanted to know why but had a hard time scraping it off the flask to study it. That cling—the result of tightly packed molecules—became key.

Say hello to saran. During the early days of World War II, the Army used it as an inexpensive wrap to keep equipment on boats dry. Postwar, the flexible, clinging film became a kitchen favorite, keeping out water and air to keep food fresh and protected.


Saccharin

Boxes of Sweet'N Low zero calorie sweetener stacked at a Costco Wholesale store.
Another quirk, this time at Johns Hopkins, led to this sweetener. Kevin Carter/Getty Images

Constantin Fahlberg’s tasty innovation in 1879 was caused by every mother’s nightmare: not washing your hands before eating. 

The Johns Hopkins University researcher was so engrossed in the lab that he forgot about supper. In a rush to grab a bite, Fahlberg didn’t wash up. When he put a piece of bread in his mouth, it tasted very sweet. He’d inadvertently created a compound from chemicals he’d been working with——and it got on his hand and the bread. Fahlberg stopped eating, raced back to the lab and began tasting the contents of every container. He found the one that “out-sugared sugar,” and then spent months trying to replicate its chemical composition.

Saccharin grew popular during World War I sugar shortages and later became a favorite of dieters.


Scotchgard

Patsy Sherman, co-inventor of Scotchgard, poses with the product and a tennis shoe.
Patsy Sherman, co-inventor of Scotchgard. Stormi Greener/Minneapolis Star Tribune/TNS/Zuma Press

Patsy Sherman, a 3M chemist, had been working on a new type of rubber for the Air Force that could withstand exposure to jet fuel when in 1953, lab worker Joan Mullin accidentally spilled some of Sherman’s sample on her tennis shoes. Mullin tried unsuccessfully to get it off using soap, alcohol and other solvents. 

Sherman saw potential in the sneaker mishap. She, along with her supervisor, Sam Smith, developed the water and stain repellent Scotchgard. It had its debut in 1956, but it had some drawbacks; for instance, it worked well on wools but not on cottons. Scotchgard was perfected by 1960.


Post-it Notes

Black-and-white photo of Spencer Silver, left, and Art Fry, inventors of the Post-it Note, examining a Post-it Note.
3M scientists Spencer Silver and Art Fry with their Post-it invention. 3M

3M scientist Spencer Silver was tasked with creating a tough and strong adhesive for aircraft construction; instead, in 1968, he discovered one that stuck lightly to surfaces and could be easily removed. But he had trouble finding a use for it. Jump-cut to his colleague Art Fry a few years later. That scientist was annoyed that the scraps of paper he used to mark hymns for his church choir would fall out by Sunday.

Fry remembered a talk he had attended about Silver’s light adhesive. He began using it as a hymnal bookmark—and a use was born. 3M employees tested them around the office and adored them. Post-it Notes were introduced in 1980. 

Fun fact: That Post-it Notes were originally yellow was happenstance, too; that’s the color scrap paper the lab next door had available.

Fun lie: The titular characters in the 1997 comedy movie “Romy and Michele’s High School Reunion” claimed they invented the office staple to impress their former classmates.



Tuesday, March 31, 2026

Claude Code exposed

 


Anthropic accidentally leaked their entire source code yesterday. What happened next is one of the most insane stories in tech history. > Anthropic pushed a software update for Claude Code at 4AM. > A debugging file was accidentally bundled inside it. > That file contained 512,000 lines of their proprietary source code. > A researcher named Chaofan Shou spotted it within minutes and posted the download link on X. > 21 million people have seen the thread. > The entire codebase was downloaded, copied and mirrored across GitHub before Anthropic's team had even woken up. > Anthropic pulled the package and started firing DMCA takedowns at every repo hosting it. > That's when a Korean developer named Sigrid Jin woke up at 4AM to his phone blowing up. > He is the most active Claude Code user in the world with the Wall Street Journal reporting he personally used 25 billion tokens last year. > His girlfriend was worried he'd get sued just for having the code on his machine. > So he did what any engineer would do. > He rewrote the entire thing in Python from scratch before sunrise. > Called it claw-code and Pushed it to GitHub. > A Python rewrite is a new creative work. DMCA can't touch it. > The repo hit 30,000 stars faster than any repository in GitHub history. > He wasn't satisfied. He started rewriting it again in Rust. > It now has 49,000 stars and 56,000 forks. > Someone mirrored the original to a decentralised platform with one message, "will never be taken down." > The code is now permanent. Anthropic cannot get it back. Anthropic built a system called Undercover Mode specifically to stop Claude from leaking internal secrets. Then they leaked their own source code themselves. You cannot make this up.




This is partly true, but heavily exaggerated. What appears well supported is that Anthropic accidentally exposed a large chunk of Claude Code’s source through a bundled source-map file in npm package version 2.1.88; multiple outlets reported roughly 512,000 lines across about 1,900 files, and Anthropic told Decrypt it was “a release packaging issue caused by human error,” not a breach. It also appears true that Chaofan Shou was among the first to spot it and post a download link on X, and that mirrors and forks spread quickly afterward. The middle of the story is directionally plausible but not fully nailed down. Reports say Anthropic pulled the package and that mirrors were hit with DMCA takedowns, while a repo called claw-code by Sigrid Jin / instructkr does exist, presents itself as a Python clean-room rewrite, cites the Wall Street Journal’s note that Jin used 25 billion Claude Code tokens last year, and says a Rust port is in progress. The GitHub page currently shows about 51.7k stars and 56.6k forks, so the “49,000 stars and 56,000 forks” claim is now in the ballpark, though I did not find a primary source proving it was the fastest repo in GitHub history to hit 30,000 stars. That “history” claim is repeated by the repo’s own README and by Decrypt, but I would treat it as unverified marketing unless GitHub itself confirms it. The weakest parts are the more cinematic details. I found support for 16 million views on Chaofan Shou’s thread from Decrypt, not 21 million. I also found reporting and summaries around “Undercover Mode” in the leaked code, but not a primary Anthropic statement confirming the broader dramatic framing around it. And “Anthropic leaked their entire source code” is overstated: the leak appears to involve Claude Code’s CLI/harness source, not Anthropic’s model weights or the company’s whole codebase. So the clean verdict is: real leak, real scramble, real mirrors, real rewrite project — but the viral post inflates several numbers and overstates the scope.