What Accident Most Changed the Course of History?

A big question

Graham Roumieu

Debbie Sterling, founder and CEO, GoldieBlox

Patsy Sherman, along with her colleague Sam Smith, discovered Scotchgard more than 50 years ago during a spill while developing a new kind of rubber for jet fuel lines. Her accident revolutionized cleaning and reminded inventors everywhere not to be disappointed if something doesn’t come out the way you expect it to.

Nancy Tomes, author, Remaking the American Patient

In 1848, the chemist Louis Pasteur got a job at a university in French wine country, where he started wondering why wine goes sour. He followed a hunch—it’s because of a microbe—and leapt from there to the hypothesis that microbes make us “sour,” too. Voilà, the germ theory of disease. We get much longer lives, plus better wine (and beer and milk!) in the bargain.

Jonathan Kay, editor in chief, The Walrus

In 1536, Henry VIII fell from his horse during a joust and was badly injured. A shocked Anne Boleyn miscarried a male fetus, sealing her fate. The onetime athlete-king would grow crippled, fat, reclusive, tyrannical, and intolerant. How would the Protestant Reformation have ended if he’d remained on that horse?

Laurence Gonzales, journalist and author

In 1928, a dish of Staphylococcus bacteria in the lab of Alexander Fleming was accidentally contaminated with Penicillium notatum mold. Ernst Boris Chain and Howard Walter Florey took up the development of penicillin in the 1930s, and the three shared a Nobel Prize for their work in 1945. The number of lives that have been saved by the drug is impossible to know.

Graham Roumieu

J. Kenji López-Alt, author, The Food Lab

In 1872, the photographer Eadweard Muybridge set up cameras to take photos in quick succession, in an attempt to settle a debate on whether all four hooves of a horse leave the ground during a gallop. This spurred the development of the motion picture, without which the incomparable deliciousness of movie-theater-style popcorn would not exist today.

Bill Nye, the Science Guy

In the early 1880s, the railroad engineer Beauchamp Tower was studying train-car axles. He drilled a hole in a metal bearing to add some oil, but the cork kept popping out. So did a stiff wooden peg. He discovered that oils get squeezed to surprisingly high pressures, which any machine has to contain. It’s how our modern world rolls.

Sara Seager, professor of planetary sciences and physics, MIT

The glow from a gas in a tube with electric current was persistent. Even when the tube was covered, “invisible rays” lit up a nearby screen with a faint fluorescent light. Wilhelm Roentgen investigated—and in 1895 discovered X-rays, revolutionizing medical diagnostics.

Shazad Latif, actor, Penny Dreadful

The discovery of fire as a cooking tool. The ability to cook our food radically changed the course of human nature. Less time needed for chewing gave more time for thinking, though perhaps not for the better. Thought separating us so clearly from other species has brought us a lot of problems spiritually. Damn that barbecue.

Graham Roumieu

Reader Responses

Eric Hanson, Germantown, Wis.

My vote is a combination of two accidents: Three Mile Island and Chernobyl. Imagine how different our energy landscape would be today without the reflexive fear of nuclear power thanks to those two events.

T. S. Folke, Skokie, Ill.

June 28, 1914: Archduke Franz Ferdinand’s driver turned down the wrong street in Sarajevo. Gavrilo Princip, a Serbian nationalist who happened to be on that street, seized the opportunity and assassinated the archduke and his wife, triggering World War I.

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