Maps

I am interested in references that describe the technology used to
create maps in pre-civil war America.  The map generating my query
was drafted by J.P. Ayres and engraved by Doolittle and Munson of
Cincinnati, Ohio in 1833. My specific question is whether a varnish
was employed as part of the original manufacture.  Any information
would be appreciated.


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                  Conservation DistList Instance 18:10
                 Distributed: Thursday, August 5, 2004
                       Message Id: cdl-18-10-030
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