The Mistakes That Made Us

In the 1920s, chemists searching for a solution to engine knock helped create one of the most widespread public health disasters in history. Leaded gasoline promised smoother-running cars and bigger profits, but at a cost that would not be fully understood for decades. In this episode of  The Mistakes That Made Us , Stephanie Einstein Tashiro traces the rise of tetraethyl lead from a celebrated te...

A naval engineer trying to stabilize equipment during World War II accidentally knocked a spring off a shelf and watched it “walk.” That mistake became the Slinky, one of the most recognizable toys in American history. But the real story goes far beyond the invention itself. In this episode, we explore the physics behind the Slinky’s strange motion, the rise of the toy as a cultural icon, and the...

In 1945, a melted chocolate bar in an engineer’s pocket set off a chain reaction that would transform kitchens around the world. This episode tells the surprising story of Percy Spencer and the invention of the microwave oven—from its origins in military radar technology to its role in reshaping how (and what) we eat. Along the way, we clear up common misconceptions about microwave radiation, expl...

In 1968, 3M chemist Dr. Spencer Silver set out to create a powerful new adhesive for aircraft. What he ended up with was… not that. Instead, he developed a glue so weak it could be peeled off and reused without leaving a trace. For years, no one knew what to do with it—until a frustrated choir singer named Art Fry needed a bookmark that wouldn’t fall out of his hymnal. In this episode of The Mista...

A happenstance lab mistake in 1928 leads to millions of lives saved.