Associated with the hat making business, how do felt and mercury produce mad hatters?
Felt hats have been produced from small animal pelts since about the 14th century. During the 19th century, fur was removed from the skin using camel urine. Some hatters used their own urine, instead. The active ingredient in urine was nitrogen-rich urea.
Those who used their own urine and were being treated for syphillis produced superior felt! This was due to the mercurous chloride (HgCl) they’d taken as medicine. Urine was replaced by orange-colored mercuric nitrate Hg(NO₃)₂.
The vats of solution and the drying process generated dangerous levels of mercury fumes. They were a source of chronic poisoning. Chronic mercury poisoning leads to tremors, mood disorders, and dementia.
Victims were called “mad hatters.” A mad hatter is one of the best known characters in Lewis Carroll’s Alice in Wonderland. The term mad hatter has become a synonym for a crazy person.
Note: You might also enjoy What Drove Russian Tsar Ivan the Terrible Mad?
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6 thoughts on “Mad Hatters, Felt, and Mercury”
[…] toxic, even in small doses. In humans, large doses cause lethargy and depression. Smaller amounts result in dementia. But what does low-dose mercury poisoning do to a bird? John P. Swaddle of the College of William […]
[…] V. Summers (2012). Mad Hatters, Felt and Mercury (online). USA, https://www.quirkyscience.com/mad-hatters-felt-and-mercury/, accessed 23rd November […]
I always felt the character of The Mad Hatter was too extreme until I was old enough to learn about mercury poisoning.
[…] new. Here’s someone you might remember from 150 years ago. The expression “mad as a hatter” came from the mercury absorbed by people making felt hats. Did I mention that two years ago the Trump administration ordered a rollback of mercury […]
[…] new. Here’s someone you might remember from 150 years ago. The expression “mad as a hatter” came from the mercury absorbed by people making felt hats. Did I mention that one year ago the Trump administration ordered a rollback of mercury […]
[…] https://www.quirkyscience.com/mad-hatters-felt-and-mercury/ […]