This feature was first published in August 2024 in My Mensa Weekly, our exclusive newsletter for Mensa members. Find out more about becoming a Mensa member here.
Words: Joanna Cummings
Discover how a little bit of luck and a whole lot of curiosity turned accidents into accomplishments
Some of the world’s greatest inventions weren’t born out of meticulous planning or careful design – they happened entirely by accident. From sticky notes to chocolate chip cookies, these serendipitous discoveries remind us that sometimes the best ideas come from happy mistakes. Here’s a list of accidental inventions that have shaped our lives in ways their creators never imagined…
Sequins: These colourful spangles are now a fundamental element of our annual festive outfits. They were discovered in the 1930s by costume designer Herbert Lieberman, while he was trying to make metallic paint. The gelatin he was using for a shiny finish melted unexpectedly, creating tiny, reflective discs. As these were fragile – they could melt in the rain – he worked with the Kodak company to create sequins that were more substantial.
Smoke alarms: In 1951, Walter Jaeger, a Swiss physicist, accidentally discovered the smoke alarm while developing a sensor for detecting poisonous gas. It wasn’t successful for that – but it did detect and react to his cigarette smoke. This led him to develop the first ionisation smoke detector, and it’s hard to put a figure to how many lives he’s saved as a result.
Post-its: In 1968 Spencer Silver, a scientist at the company 3M, was trying to create a super-strong adhesive but accidentally created a weak, repositionable one. Six years later, his colleague, Art Fry, made a bookmark using this glue and placed it in his hymn book. When Fry noticed that it didn’t damage the fragile pages, it led to the invention of the ‘Press n’ Peel’ – what we now know as the indispensable Post-it note.
Microwaves: This useful kitchen device derived from an accidental discovery in 1945 by Percy Spencer, an engineer working with radar technology. While standing near a magnetron, he noticed a chocolate bar in his pocket – a Mr Goodbar, if you’re interested – had melted. This led Spencer to investigate further, ultimately developing the first microwave oven and transforming cooking with electromagnetic radiation.
Velcro: We have a certain Swiss engineer, George de Mestral, to thank for Velcro (the name comes from the French words ‘velour’ and ‘crochet’, meaning velvet and hook, respectively). After noticing cockle-burrs attaching themselves to the coat of his dog during a 1941 hiking trip, he examined them under the microscope and discovered the ‘hook and loop’ mechanism – this inspired the genuinely revolutionary product we use today on everything from sports shoes to kitchen blinds.
X-rays: This indispensable medical procedure was accidentally discovered in 1895 by German physicist Wilhelm Conrad Roentgen while he was testing whether cathode rays (streams of electrons) could pass through glass. He noticed a fluorescent glow on a nearby screen, despite it being covered. Roentgen realised the invisible rays could pass through objects, including human tissue, leading to the development of life-changing medical imaging.
Anaesthesia: Victorians may have a bad rap as our dull and restrictive ancestors, but even they could let their hair down. It was during ‘laughing gas parties’, prevalent in certain echelons of society, that it was discovered that nitrous oxide (laughing gas) also numbed pain, helping with the development of painless surgery.
Pacemakers: One of the first implantable pacemakers was accidentally invented in 1956 by Wilson Greatbatch, an engineer working on a heart rhythm recording device – though many decades of research preceded this discovery. Greatbatch mistakenly used the wrong resistor, causing the circuit to emit a rhythmic electrical pulse. Realising its potential to regulate heartbeats, Greatbatch refined the device, and 1960 saw its first human recipient.
The Slinky: Back in 1943 when Naval engineer Richard James was developing springs to stabilise ship instruments, one of them fell off a shelf and ‘walked’ across the floor. Intrigued by its motion, James adjusted the spring’s design and the Slinky became a classic toy beloved by generations…as well as a trip hazard for unwary house guests.
Matches: In 1826, an English pharmacist called John Walker was using a stick to stir a mixture of chemicals, which coated the wood. When he scraped it against the hearth of his home, it burst into flame, thus creating the first ever ‘friction match’.
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