The Mad Hatter was a real medical diagnosis. 🎩

The Mad Hatter was a real medical diagnosis. 🎩 . . . For generations, hat factories in Danbury, Connecticut treated felt with mercury nitrate. The fumes wrecked workers' nervous systems — tremors, slurred speech, paranoia, hallucinations. Locals called it the 'Danbury Shakes.' The US only banned mercury in hat-making in 1941. Lewis Carroll wasn't inventing anything.