Hi, Susan -

I'd suggest NOT doing any enhancing of any kinds.  When I worked at
the Library of Congress (Geography and Map Division, what else?), I
got in a lengthy discussion with Mrs. LeGear and Mr. Pillsbury about
people who "clean things up"  if they are old and dirty/dusty.  One of
the observations I had was that it seemed to me "fixing" ought not to
be done to anything old unless it was the "regular" way it had been
maintained.

For example, if the "old thing" had been leather and it had been
regularly "cleaned", continuing to use the same way of cleaning
probably makes sense, but a very bad thing to do if it had NOT been
regularly cleaned.  My thinking was that two or three hundred years of
grit and grime is part of the object and I made that point to them
(keeping in mind that I was rising junior at GWU at that particular
time and that my major was geography, not conservatorship!).

In the case of the plates, it seems to me that the way to go might be
to mount them such that you could show the engraving work by shining a
not-colored light in a way that the "art" would be visible to the
viewer, perhaps by shining a light across the surface of the plate.

Having scans of the three plates to be able to make illustrations
digitally for display might be a really excellent idea as well.  I can
see, in my mind's eye, an exhibit I saw someplace in Europe (but
wasn't allowed to photograph) where the exhibit used the scan(s) to
create part of a display which showed how engraving was different from
lithography and how the engraving would almost be more of an art work
than lithography is in many folks' minds.  I concluded that their
choice of words reflected a wrong conclusion on the part of the
designers/creators of that exhibit.  ;~(

But, I still believe, probably based on my very early decision at age
9 or 10 not to use stamp hinges, that things we save because they're
old or made by an historic figure (Ben Franklin's Almanacs?) or just
because they're historic documents on their own (the Plan of
Washington DC that used to be available at the old Coast and Geodetic
Survey, ought not to be damaged!

In a used bookstore in DC in 1964, I came on a book that purported to
be a printing of Captain Cook's journal at the time when he apparently
sailed in the North Pacific.  I bought it for $4.50 that summer and
the only thing I've done since, because its binding was not in the
finest shape,is to use a hand blower that lives in my very old
photography kit to gently remove dust once or twice a year.  I talked
to a conservator at the Huntington Library about what kinds of
precautions he'd take and he said that he'd probably keep it in place
with well-maintained temperature and humidity controls, which I do
except when reading it (which I also do a couple of times a year).

You might contact the Geography and Map Division and find out who
keeps track of the powder horn maps and other raries (my name for old
stuff).  Certainly, nobody was applying cleaners of any kind to the
powder horns when I worked there.  And, as for things like the WWII
maps captured from Germany and Japan, they were mostly preserved in
that, when I worked at LC by being well-organized so that they didn't
wind up being accidentally dinged when somebody was looking for
something else and didn't know which drawer(s ) it/they might be in.
Given that most of the operational maps used by the military were
printed on relatively inexpensive (cheep might be a better word)
paper, I wonder what state they're in today?

Finally, if somebody at LC can't suggest how to display/maintain the
plates, I'm reasonably certain somebody on this list will have ideas.
Also, I have a couple of friends who work at the Getty Conservation
Institute here in LA and could ask them what they suggest as a way to
display the copper plates without damaging them, if you like.

Congrats on your acquisition.  The thought crossed my mind when I
first heard about the sale of the plates, but since I'm retired now,
I'm downsizing not upsizing.  And, in any case, I'm certainly not
nearly as persistent as you have been!

Hope this helps.

virginia
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Virginia R. Hetrick, here in sunny California
Email:  [log in to unmask]
"There is always hope."
My fave:  http://www.washington.edu/cambots/camera1_l.jpg
There's no place like:  34N 8' 25.40", 117W 58' 5.36"
if you can't be at:  48N 7' 4.54" 122W 45' 50.95"
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