Word Routes

Exploring the pathways of our lexicon

Mailbag Friday: "Mad Hatter"

Today's question for Mailbag Friday comes to us from Valerie P. of Ottawa, Ontario. Valerie writes: "I was visiting a heritage village in Nova Scotia when a guide in a traditional tailor's house told me the origin of the expression, mad hatter. He said that the beaver fur the popular top hats were made of was preserved with mercury. The workers gradually absorbed this mercury while making the hats and eventually became mad. The explanation seems a bit sketchy; can you fill in the details, or correct the explanation?"

One of my basic rules of thumb is that when it comes to etymology, never trust tour guides. The job of a tour guide, after all, is to entertain people with fanciful stories about a particular place, not to be a serious word historian. If you're visiting New York City, for instance, you might hear a tour guide tell you an apocryphal story about how 23 skidoo comes from police slang used to disperse crowds of ogling men in front of the Flatiron Building on 23rd Street, where high winds would blow up women's skirts. (See here for more on skidoo. We're not sure where the "23" comes from, but Barry Popik, master word sleuth and bane of the tour guides, points out that the number appeared in slang expressions well before the construction of the Flatiron Building.)

In her trip to Nova Scotia, Valerie has come across that special case of a tour guide who actually seems to care about etymological veracity. The explanation that the guide gave is pretty much on the money. We're all familiar with the famous tea party in Lewis Carroll's Alice's Adventures in Wonderland, presided over by the Mad Hatter. Carroll, who published the children's classic in 1865, came up with the character based on the expression as mad as a hatter, which the Oxford English Dictionary dates back to 1829. As the OED explains, "the allusion is to the effects of mercury poisoning sometimes formerly suffered by hat-makers as a result of the use of mercurous nitrate in the manufacture of felt hats."

Those felt hats were very often made of beaver pelts or other animal fur, as the tour guide suggested. In the heyday of hatmaking, one center of industry was Danbury, Connecticut, nicknamed "The Hat City." Peg Van Patten of the Connecticut Sea Grant writes about how mercury poisoning afflicted the hatmakers of Danbury:

At the peak of the industry, five million hats a year were produced in 56 different factories in Danbury. A process called "carroting" was used in the production, but it had nothing to do with vegetables. Carroting involved washing animal furs with an orange-colored solution containing a mercury compound, mercury nitrate.
The colorful solution facilitated the separation of the fur from the pelt and made it mat together smoothly. The fur was then shaped into large cones, then shrunk in boiling water and dried many times before final shaping, smoothing, and finishing. Workers would often be exposed to mercury vapors in the steamy air. Many hatters with long-term exposure, particularly those involved in carroting, got mercury poisoning.
Mercury poisoning attacks the nervous system, causing drooling, hair loss, uncontrollable muscle twitching, a lurching gait, and difficulties in talking and thinking clearly. Stumbling about in a confused state with slurred speech and trembling hands, affected hatters were sometimes mistaken for drunks. The ailment became known as "The Danbury Shakes." In very severe cases, they experienced hallucinations.

Outside of Danbury, the physical effects of mercury poisoning on hatmakers was simply called "hatter's shakes." Fortunately for the hatters, mercury nitrate stopped being used in the production of hats in the 1930s, when new processes involving hydrogen peroxide and acids were developed.

Clearly, being a hatmaker back in olden times was a tough job. But even those suffering "hatter's shakes" would rarely exhibit psychological disorders that we associate with "madness." That, as it turns out, was more of a popular perception than a medical reality. Despite the fact that there weren't many hatmakers actually going mad from exposure to mercury, common stereotypes about the occupation were enough to give rise to the phrase as mad as a hatter and ultimately inspire Lewis Carroll. Now, where Carroll got the idea for another mad creation, the March Hare, is a story for another day.

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Ben Zimmer is executive producer of the Visual Thesaurus and Vocabulary.com. He is language columnist for The Wall Street Journal and former language columnist for The Boston Globe and The New York Times Magazine. He has worked as editor for American dictionaries at Oxford University Press and as a consultant to the Oxford English Dictionary. In addition to his regular "Word Routes" column here, he contributes to the group weblog Language Log. He is also the chair of the New Words Committee of the American Dialect Society. Click here to read more articles by Ben Zimmer.

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Comments from our users:

Friday August 8th 2008, 10:25 AM
Comment by: Scott L. (Hamden, CT)
This derivation of "mad hatter" has always been known to Connecticut School children. I don't remeber ever NOT knowing its roots.
Saturday August 9th 2008, 12:39 PM
Comment by: Roger Dee (Haslett, MI)Top 10 Commenter
As a medical doctor I have always enjoyed studying the "occupational" diseases. So, when I read the explanation of the "mad as a hatter" and find it accurate and detailed I know I made a good choice subscribing to the Visual Thesaursus. I like to see excellence in publishing! Good job!!
Saturday August 9th 2008, 8:17 PM
Comment by: Christine H.
That was fascinating. It made me think about the number of expressions we take for granted without knowing about their derivation. It also made me think about how we are taught expressions in school without any explanation.

How much more interesting learning would be if our teachers would explain the context.

Could someone recommend a reference book for such expressions? I would love to have one.
Sunday August 10th 2008, 5:11 AM
Comment by: Gill F.
Brewers Dictionary of Phrase and Fable is a good one . Here's the blurb for it from Amazon:

"Product Description
'...there's never a dull moment to be had with this great, daft, pointless, wonderful brick of a book' - Amazon.co.uk 'John Ayto has done a brilliant job bringing our phrase and fable right up to date' - Daily Express First published in 1870, Ebenezer Bobham Brewer's treasury of 'words that tell a story' is one of the world's best-loved reference books. At the heart of the dictionary lie entries on the meaning and origin of a vast range of words and expressions, from everyday English phrases to Latin tags. For the 17th edition, new editor John Ayto has revised and updated the existing text and added 1500 new articles, including words and phrases (Al-Qaeda, 9/ll), characters, places (and monsters) from fantasy literature (including The Lord of the Rings and Harry Potter), famous political and sporting nicknames (Butcher of Baghdad, Goldenballs) and continuing the century-old Brewer's practice of recording unexpected and fascinating information not available in other reference books - 'list entries' as diverse as misattributed quotations, first lines of novels, 'etymologies of group names and French/Spanish/German/Italian idioms."
Sunday August 10th 2008, 3:55 PM
Comment by: Christine H.
Thank you, Gill. It sounds like fun.

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