Early internal combustion engines were subject to “knocking,” a metallic rattle that indicated something wasn’t right. GM engineer Thomas Midgley was assigned the task of identifying the cause and the cure. It turned out that knocking was caused by premature combustion in the engine, and the solution Midgley and GM hit upon was a fuel additive: tetraethyl lead. Soon car and airplane engines everywhere were fueled by leaded gasoline. Midgley went on to a second triumph: the development of chlorofluorocarbons as refrigerants.
By the time of his death in 1944, Midgley was being hailed as one of the eras great inventors. But by the last quarter of the twentieth century, a great effort would be undertaken to undo his inventions.
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When I was growing up in Philadelphia in the 50s and 60s I remember a device on public display near City Hall that recorded the amount of lead in the air.
Veritasium put out a video today about this exact subject: https://youtu.be/IV3dnLzthDA
Although I recall leaded gasoline and the effort to remove lead from gas, I was not aware of the origin story until a few months ago. This topic was discussed in the History of Chemistry podcast. That podcaster was much harsher on Mr. Midgely than you, Mark.
I was aware of Claire Patterson from my academic reading as a grad student. In 1989, as a post-doc at Cal Tech, I was in Lee Silver’s research lab (for more about Silver, see Episode 10 of HBO’s From the Earth to the Moon). One afternoon, an elderly man stopped by and asked if Lee was around. I said no, and the man asked me to tell Lee that Claire Patterson had dropped by. When I got home, I told my wife that I had just met the man who had calculated the age of the Earth. For an academic geochemist, it was quite a day!