Humidifying maps

We possess several folded Civil War battlefield maps produced by the
"Margedant Quick Map Method" and would like advice on how to
humidify and flatten them for microfilming.  Some are printed on
cloth and some on paper.

The Margedant Method involved treating the paper with a
photo-sensitive chemical, overlaying the paper with a tracing of the
battlefield view and placing them out in the sun.  This resulted in
a map that appears something like a brown-colored paper negative.
The maps were usually colored to highlight troop positions and
terrain features.  I assume that a similar process was used for
cloth maps, but have seen any literature on it.

If anyone has any suggestions on how we might proceed--other than
testing the colors with Q-tips dipped in distilled water--we would
appreciate hearing from you.  Thank you.

Bill Barrow, Cartographic Specialist
The Western Reserve Historical Society Library
Cleveland, Ohio

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                  Conservation DistList Instance 9:17
                 Distributed: Thursday, August 17, 1995
                        Message Id: cdl-9-17-015
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