Hatmakers over the past three centuries used mercury in their work, and some hatters experienced nervous disorders, odd behavior, and even symptoms of madness. But why were the hatters mad? Did the brim curlers sniff glue? No, what they sniffed was mercury.
But the story doesn't end there. Mercury left from the hat industry, before its use was banned in the 1940's, has left a legacy still with us today in some parts of Connecticut.