Most excellent and interesting thread.
Not to hijack - rather in case someone is interested in a simple and effective preservation technique:
Here in New England there are many old, lost cemeteries/burial grounds. Many can be found thru local libraries. Often there is an Historian at your local library and/or historical society who can help find/locate these hallowed grounds, and many of these folks are desperate for folks to find and help preserve the history/information on these old stones.
My son did his Eagle Scout project in response to this need; in the oldest section of a local cemetery where many of the stones were deteriorating and difficult to read, and, he devised a way to capture the info on the stones w/out touching them, simply by taking pictures of the stones - at night, w/ hand-held lighting.
Of course requires getting out at night.

Then he catalogued the information and created a web site(FREE space avail off ancestry dot com) hopefully to preserve the info in perpetuity. If someone would like to do a similar preservation project to help your town/county or your very own family:
http://freepages.genealogy.rootsweb....l/default.html
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nighttime:
Thanks for the work and sharing a Wonderful, Thoughtful RR !
All the Best, dean