17 Everyday Things That Were Invented by Accident (From Corn Flakes to Dynamite to the Guillotine)

Many iconic inventions emerged not from careful design, but from unexpected discoveries and happy accidents. This list explores 20 household staples and world-changing devices that originated from unexpected mistakes, mishaps, or serendipitous events — from breakfast cereals and sticky notes to lifesaving drugs and powerful explosives.

1. Corn Flakes

In 1894, Dr. John Harvey Kellogg and his brother Will Keith Kellogg were experimenting with boiled wheat to create a healthy, easily digestible bread substitute for patients at the Battle Creek Sanitarium in Michigan. They accidentally left a batch of boiled wheat sitting out overnight, causing it to become stale. When they passed the stale wheat through rollers, it separated into thin flakes. They toasted these flakes, resulting in a crispy, nutritious food that became known as “Granose.” Later, they applied the same process to corn, creating the first corn flakes. This innovation revolutionized breakfast and led to the founding of the Kellogg Company. (inventionandtech.com)

2. Dynamite

In 1864, Alfred Nobel’s nitroglycerin factory exploded, resulting in the tragic death of his brother Emil and several others. Determined to make nitroglycerin safer, Nobel experimented with various substances to stabilize it. He discovered that mixing nitroglycerin with kieselguhr, a porous siliceous earth, transformed the liquid into a paste that could be safely handled and shaped into rods. In 1867, he patented this invention, naming it “dynamite,” derived from the Greek word “dynamis,” meaning “power” (nobelprize.org). Dynamite revolutionized construction and mining by enabling efficient blasting of tunnels, canals, and roads. However, its potential for destruction led Nobel to establish the Nobel Peace Prize, aiming to offset the harmful uses of his invention. (history.com)

3. The Guillotine

In 1789, Dr. Joseph-Ignace Guillotin, a French physician and politician, proposed a more humane method of execution to replace the often botched beheadings by sword or axe. He advocated for a device that would decapitate swiftly and painlessly, ensuring equality in death for all classes. Although he did not invent the guillotine, his name became associated with it. The actual design was developed by physician Antoine Louis and engineer Tobias Schmidt, resulting in the efficient execution device known as the guillotine (history.com).

4. Penicillin

In 1928, Dr. Alexander Fleming returned from a vacation to find that a mold had contaminated a petri dish containing colonies of Staphylococcus bacteria in his laboratory at St. Mary’s Hospital in London. Upon closer examination, he observed that the bacteria surrounding the mold were destroyed, while those farther away remained unaffected. Recognizing the potential significance of this observation, Fleming identified the mold as belonging to the genus Penicillium. He named the antibacterial substance it produced “penicillin.” This serendipitous discovery marked the beginning of the antibiotic era, revolutionizing medicine and saving countless lives (sciencehistory.org).

5. Sticky Notes (Post-it Notes)

In 1968, Dr. Spencer Silver, a scientist at 3M, was attempting to develop a super-strong adhesive. Instead, he accidentally created a low-tack, reusable adhesive that stuck lightly to surfaces but didn’t bond tightly. For years, Silver struggled to find a practical application for his invention. In 1974, his colleague Art Fry, frustrated by bookmarks falling out of his church hymnal, remembered Silver’s adhesive. Fry applied it to paper, creating a repositionable bookmark. Recognizing its potential, they developed the Post-it Note, revolutionizing office communication (post-it.com).

6. Microwave Oven

In 1945, while working on radar technology at Raytheon, engineer Percy Spencer noticed that a chocolate bar in his pocket had melted. Curious, he experimented by placing popcorn kernels near the radar equipment, observing them popping. Further testing with an egg resulted in it exploding, confirming that microwaves could cook food rapidly. Spencer and his team developed the first microwave oven, the “Radarange,” which was introduced commercially in 1947. This innovation revolutionized cooking by providing a quick and convenient method to heat food (popularmechanics.com).

7. Potato Chips

In 1853, Chef George Crum, also known as George Speck, worked at Moon’s Lake House in Saratoga Springs, New York. A customer repeatedly sent back his French fries, complaining they were too thick and soggy. Frustrated, Crum sliced potatoes as thinly as possible, fried them until crisp, and salted them heavily, expecting the customer to be displeased. To his surprise, the customer loved them, and soon other patrons requested the same. These crispy slices became known as “Saratoga Chips,” marking the accidental creation of the potato chip (britannica.com).

8. X-Rays

In 1895, while experimenting with cathode rays in his laboratory at the University of Würzburg, German physicist Wilhelm Conrad Röntgen noticed that a fluorescent screen in his lab began to glow, even though it was shielded by heavy black paper. Curious, he investigated further and discovered that the cathode rays were producing a new form of radiation that could pass through various materials, including human tissue, but not bones or metals. He named this phenomenon “X-rays” to denote their unknown nature. Röntgen’s accidental discovery revolutionized medicine by providing a non-invasive method to view the interior of the human body, leading to the development of diagnostic imaging techniques (history.com).

9. Velcro

In 1941, Swiss engineer George de Mestral was hiking in the Alps with his dog when he noticed burrs from the burdock plant clinging to his clothing and his dog’s fur. Curious about how these burrs adhered so tenaciously, he examined them under a microscope and observed hundreds of tiny hooks on their surface. Inspired by this natural mechanism, de Mestral envisioned creating a two-sided fastener: one side with hooks and the other with loops. After years of experimentation, he patented the hook-and-loop fastener in 1955, naming it “Velcro,” a combination of the French words “velours” (velvet) and “crochet” (hook). Velcro revolutionized fastening systems and is now ubiquitous in products ranging from clothing and footwear to aerospace equipment (smithsonianmag.com).

10. Safety Glass

In 1903, French chemist Édouard Bénédictus was working in his laboratory when he accidentally dropped a glass flask that had previously contained cellulose nitrate, a flammable liquid. To his surprise, the flask shattered but the pieces remained largely intact, held together by a thin film of cellulose nitrate that had coated the interior. Intrigued by this phenomenon, Bénédictus realized that embedding a layer of cellulose nitrate between two sheets of glass could prevent shattering and enhance safety. He patented this innovation in 1909, naming it “Triplex” glass. This laminated safety glass was initially used in automobile windshields, significantly reducing injuries from glass shards in accidents. Over time, the cellulose nitrate was replaced by polyvinyl butyral (PVB) due to its superior strength and clarity, leading to the modern safety glass widely used today (britannica.com).

11. Vulcanized Rubber

In 1839, Charles Goodyear, an American inventor, was striving to make rubber more durable and less sticky. While experimenting with a mixture of rubber and sulfur, he accidentally dropped it onto a hot stove. To his surprise, the rubber didn’t melt; instead, it charred like leather. Recognizing the potential of this transformation, Goodyear refined the process, leading to the development of vulcanized rubber—a material that was elastic, durable, and weather-resistant. This innovation revolutionized industries, particularly in the manufacturing of tires and various rubber products. Goodyear patented his process in 1844, but despite his significant contribution, he faced financial difficulties and died in debt. The Goodyear Tire & Rubber Company, established in 1898, was named in his honor (britannica.com).

12. Pacemaker

In 1956, while working on an oscillator to record heart sounds, engineer Wilson Greatbatch mistakenly installed a 1 MΩ resistor instead of the intended 10 KΩ resistor. This error caused the circuit to emit a steady electrical pulse, mimicking the rhythm of a heartbeat. Recognizing the potential, Greatbatch collaborated with Dr. William Chardack to develop the first implantable cardiac pacemaker. In 1960, they successfully implanted the device in a human patient, marking a significant advancement in medical technology (lemelson.mit.edu).

13. Artificial Sweeteners (Saccharin)

In 1879, while researching coal tar derivatives at Johns Hopkins University, chemist Constantin Fahlberg accidentally discovered saccharin, the first artificial sweetener. After a day in the lab, he sat down to dinner without washing his hands and noticed that his bread tasted unusually sweet. Realizing that the sweetness was due to a chemical he had been working with, Fahlberg identified it as benzoic sulfimide, which he later named saccharin. This discovery led to the development of a sugar substitute that is approximately 300 times sweeter than sucrose, revolutionizing the food industry by providing a low-calorie alternative to sugar (acs.org).

14. Teflon

In 1938, while working at DuPont’s Jackson Laboratory in New Jersey, chemist Roy J. Plunkett was researching gases related to refrigerants. He and his assistant, Jack Rebok, were testing tetrafluoroethylene (TFE) gas when they found that a pressurized cylinder, which should have been empty, was unexpectedly heavy. Upon opening it, they discovered that the TFE had polymerized into a white, waxy solid. This substance, later named polytetrafluoroethylene (PTFE), exhibited remarkable properties: it was chemically inert, had a high melting point, and was extremely slippery. Recognizing its potential, DuPont patented PTFE in 1941 and registered the Teflon trademark in 1944. Initially used in military applications, Teflon’s non-stick properties later made it popular in cookware, revolutionizing the kitchen industry. Today, Teflon is utilized in various industries, including aerospace, electronics, and pharmaceuticals (teflon.com).

15. Play-Doh

In the 1930s, Noah McVicker, a compound designer for the Cincinnati-based company Kutol Products, developed a putty-like substance intended to clean soot from wallpaper. This product effectively removed grime without damaging surfaces. However, as coal heating became less common in the 1950s, the demand for wallpaper cleaner declined, threatening the company’s viability. In 1955, McVicker’s nephew, Joe McVicker, learned from his sister-in-law, Kay Zufall, a schoolteacher, that children enjoyed using the cleaner as a modeling compound. Recognizing its potential as a children’s toy, Joe McVicker rebranded the product as Play-Doh. In 1956, Play-Doh was introduced to the market, and its popularity soared, becoming a staple in classrooms and homes worldwide (smithsonianmag.com).

16. Ice Cream Cones

The origins of the ice cream cone are somewhat ambiguous, with multiple claims to its invention. One widely recognized story dates back to the 1904 St. Louis World’s Fair. During the fair, an ice cream vendor ran out of serving dishes. Nearby, Ernest Hamwi, a Syrian concessionaire selling a crisp, waffle-like pastry called zalabia, noticed the shortage. He rolled one of his warm pastries into a cone shape and offered it to the ice cream vendor, who filled it with ice cream. This innovation delighted fairgoers and popularized the ice cream cone as a convenient and edible serving vessel. However, other accounts suggest that the ice cream cone was independently invented by Italo Marchiony, an Italian immigrant in New York City, who patented a design for an edible ice cream cup in 1903. Despite these competing claims, the 1904 World’s Fair incident is often credited with popularizing the ice cream cone, making it a beloved treat enjoyed worldwide (time.com).

17. Super Glue

In 1942, while working for Eastman Kodak, chemist Harry Coover was tasked with developing clear plastic gun sights for military use during World War II. During this research, he encountered cyanoacrylate, a compound that was extremely adhesive but initially dismissed due to its tendency to bond to unintended surfaces. In 1951, Coover revisited cyanoacrylate while overseeing a team investigating heat-resistant polymers for jet canopies. Recognizing its potential as a strong adhesive, he patented the substance in 1958, marketing it as “Eastman 910.” This product, later known as Super Glue, revolutionized bonding applications in both consumer and industrial markets. Coover’s invention also found significant medical applications, including use as a hemostatic agent during the Vietnam War to control bleeding in soldiers’ wounds (invent.org).

Conclusion

These accidental discoveries highlight how unexpected events can lead to groundbreaking innovations. From life-saving antibiotics to everyday conveniences like Post-it Notes and microwave ovens, these inventions have profoundly impacted our daily lives, often in ways their creators never anticipated. They serve as a testament to the serendipitous nature of innovation, reminding us that breakthroughs can emerge from the most unforeseen circumstances (history.com).