I don't have any particular expertise on the topic of mercury, but a review article on mercury toxicity starts with the following relevant statement:

"Mercury is ubiquitous in the environment and therefore every human being, irrespective of age and location, is exposed to one form of mercury or another."

I also played with a nice wad of liquid mercury when I was a kid, and it gradually disappeared with usage, but it was one of my favorite playthings for a while.

My understanding is the same as Sharon's: it was the elemental liquid form - "quicksilver" - that was used in mining. It is not well-absorbed by the skin or by the GI tract. Or by the lungs [unless you boil it or aerosolize it, apparently]. For followers of 21st century culture, there is a new thing out there. There are also case reports of IV drug users shooting up liquid mercury to see if they can experience a new experience. They do. Death. 

The medical profession used to inject various mercury compounds into human beings; in medical school, last century, I was taught about "mercurial" diuretics that were going out of favor because of newer, safer agents. Mercury compounds are toxic to the neurologic system, appearing as ataxia [incoordination], paresthesias [numb, tingling extremities], and cognitive impairment with a dementia/delirium picture that would not be conducive to creative writing or quick wit. Or to walking across the street.[Being "mad as a hatter" may be related to the use of mercury in felt hat production. Or not.]

So I don't see any sign that Twain had excessive mercury exposure, or any consequences to the exposure he had. The people on this list who breathed lead fumes are the ones I would watch.

And that doesn't give away anything about my current project. [You have to come to Hannibal next month for that!]

Pat

-----Original Message-----
From: Mark Twain Forum [mailto:[log in to unmask]] On Behalf Of Sharon McCoy
Sent: Wednesday, July 06, 2011 11:02 AM
To: [log in to unmask]
Subject: Re: Mark's exposure to mercury

Pat, if you're online, interested, and it wouldn't give away too much of 
your new work, maybe you'd weigh in?


Cheers,
Sharon