Polygraphy, or the  "art of multiplying paintings by chemical and mechanical
means" was practiced at the end of the 18th century in England and the United
States (and elsewhere?) prior to the invention of lithography.
 
This process is the subject of my research.  Information about the
proceedures used; paintings known or believed to have been manufactured by
this "secret" process; and information about any modern scholarship on this
subject would be greatly appreciated.
 
Thanks for your help,
 
Paul D. Schweizer
Munson-Williams-Proctor Institute
310 Genesee Street
Utica, New York 13502
U.S.A.
 
(315) 797-0000 ext. 140
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