12 Inventions Created by Mistake

At Diversified Spaces, we’re all about hands-on learning. From whipping up a cake in FACE class, building a wood bench in the workshop or conducting science experiments in the lab, it’s important to encourage students to think like an inventor, and experiment and try new things – even if they make mistakes! After all, many life-changing inventions were accidentally created by everyday people. Just take a look at some of our favorites:

1. The Slinky

Who knew the slinky was accidentally invented by a naval engineer? (We definitely didn’t!). The idea came to naval engineer Richard James while he was trying to develop a spring that would support and stabilize sensitive equipment on ships. While he was working on his project, one of the springs fell off a shelf and kept moving. As James watched the spring continue to move, a light bulb went off in his head. After he decided it would make a great toy and his wife came up with the name, the Slinky was first sold in late 1945. 

2. Chocolate Chip Cookies

Could you imagine a world without chocolate chip cookies? Us either. Luckily, we can all thank Ruth Graves Wakefield, co-owner of the Toll House Inn, when she decided to bake some chocolate cookies for her guests. To make the cookies chocolate, Wakefield decided to chop up a block of semi-sweet chocolate from Nestle, hoping that the chunks of chocolate would melt and spread evenly. Instead of spreading evenly as she had hoped, out came what are now known as chocolate chip cookies! 

3. Microwave Oven

If it wasn’t for a candy bar melting in Percy Spencer’s pocket in 1945, the microwave oven may have never been invented! An engineer at Raytheon, Spencer was experimenting with a radar-related vacuum tube when he noticed the candy bar was melting in his pocket. Using his newfound knowledge, he later patented the microwave. 

4. Potato Chips

Crispy, salty and savory … what more could you want in a snack? Thanks to a New York restaurant customer complaining about the fried potatoes being too soggy and thick, Chef George Crum got so upset that he cut the potatoes into extremely thin slices, fried them and then sprinkled on some salt. I bet Crum would have never thought in a million years that he would invent one of the world’s most popular snacks – potato chips! 

5. Post-It Notes

Spencer Silver, a chemist for 3M, failed to make heavy-duty adhesive for the aerospace industry. The only thing he could make was a temporary adhesive, not strong enough to hold much weight. Low and behold, the temporary adhesive was good for something – holding bookmarks in place! Thus, removable notes were born, now known as Post-it notes. 

6. X-Rays

Did you know? X-rays were accidentally invented after trying to create lightbulbs. (Who knew?) In 1895, German scientist Wilhelm Conrad Roentgen was trying to create lightbulbs by experimenting with cathode-ray tubes. But then he noticed something interesting: when the cathode tubes were placed inside a cardboard box, they continued to emit light even though the cardboard should have stopped it. He then realized that the tubes were not only emitting light, but were also passing invisible rays that could penetrate solid matter. Soon after human experiments proved successful, X-rays became available in the medical field to check for broken bones. 

7. Penicillin

It's sometimes good to be messy – just ask scientist Alexander Fleming! In 1928, he left his lab a mess, including leaving petri dishes with bacteria in them, because he was in a rush to go on vacation. When he got back from vacation two weeks later, some of the petri dishes that he hadn't cleaned were moldy. But while he was cleaning the mold off the dishes, he noticed the bacteria had been killed. After studying the mold, he saw that one particular substance, penicillin, was responsible for getting rid of the mold. Since then, penicillin has been used to save millions of people!

8. Matches

Stirring a pot of chemicals in 1826, John Walker pulled his wooden stir stick out of the pot and tried to wipe the glob of chemicals stuck on the table. Instead of wiping off, the chemicals ignited. As a result, matches were born! 

9. Safety Glass

While working in the lab in 1903, French chemist Edouard Benedictus dropped a glass flask. Instead of shattering into a million pieces, it surprisingly shattered but didn’t fall apart. Later, he discovered that the flask had recently been filled with cellulose nitrate, which provided a protective layer. Today, safety glass is used in many applications using a similar solution to the cellulose nitrate to make it shatterproof.

10. Super Glue

During World War II, Harry Coover, a chemist for Eastman Kodak, was tasked with creating a suitable plastic for gun sights. Instead of succeeding with his task, he instead accidentally created cyanoacrylate, now known as superglue. But its potential wasn’t realized until almost nine years later when Coover was working to develop heat-resistant polymers for jet planes. Believe it or not, cyanoacrylate was the perfect solution!

11. Implantable Pacemaker

In the late 1950s, Wilson Greatbatch grabbed the wrong type of resistor out of a box while trying to build an oscillator to record the heartbeat sounds of animals. When he turned it on, he noticed that it produced a signal that mimicked the human heartbeat. As a result, the implantable pacemaker was created!

12. Velcro

While Swiss engineer George de Mestral was hiking with his dog, he noticed little burrs sticking to both his pants and dog. After looking at the burrs a little more closely, he noticed there were small hooks on the burrs that would cling to anything that was loop-shaped. With this new discovery, Mestral recognized the potential for a practical new fastener – now known as Velcro!