Sometimes the better the craftsman, the more nuts he was. It became an intriguing medical mystery.

It is probably not a coincidence that Lewis Carroll made one of his famous characters a Mad Hatter. There was a time when most of these fine craftsmen, hatters, were thought to have a touch of madness.

What an unusual medical mystery. Why was this? They mixed up their words, stammered, trembled, and shook. They were excitable and irritable. Hatter’s Shakes—this was the name given to the contortions they often made.

Sometimes the better the craftsman, the more nuts he was. The craft of hat making involved molding and training the felt over molds to get the desired shape. Down through the ages, various chemicals were tried to make a solution that would help the molding part of the craft along.

The chemicals were strong, often permeating the surrounding air. Hatters chewed huge plugs of tobacco to counteract effects of the floating chemicals. They chewed so much tobacco, that not only was the solution toxic, the tobacco was toxic in their systems.

What was poisoning the hatters? Mercury has been known to be poisonous for a long, long time—since the days of ancient Rome. The Romans would only allow their convicts to mine it. An early Yugoslavian labor law, in 1665, forbade mercury miners to work around the stuff for more than six hours a day.

Mercury can be toxic to all life forms. At room temperature, it can fly through the air invisibly, then, it can be breathed in. In the body, after inhaled, it can make itself soluble in blood and travel to vital organs, causing chronic mercury poisoning. Symptoms of this are a metallic taste in mouth, sore gums, loose teeth, twitching tongue and eyelids, stomach pains, muscle tremors in extremities, sweating and anemia.

So many hatters exhibited these symptoms that the expression mad as a hatter was bound to come into being, and it did. This horrible affliction was permanently cured at the beginning of the 20th Century when mercury was removed from the hat-processing recipe.
Sara Marie Hogg is the author of It Rises From the Pee Dee. Click HERE to find the book on Amazon.