19th century prints on vellum

The curator of our Gallery here at Leeds University recently
discovered we had a large group of prints on vellum in the
collection. All have paper secondary supports and original mounts.
Some are on wooden strainers. The vellum seems to be in good
condition but the paper elements of the prints are deteriorating
rapidly.The vellum is also detaching and cockling in some instances.

It's been proposed that the vellum and paper be separated since,
clearly, they are incompatible. The vellum will then be hinged onto
a new backboard (the curator's not concerned with keeping it under
tension and therefore flat) and the original decorative window
mounts retained.

What we'd like to know is: does anyone have experience of these
objects?  If so, did they reach similar conclusions as to their
treatment. In addition, references to historical and conservation
literature would be very welcome.

Sharon Connell
Assistant Conservation Officer
Brotherton Library
Leeds University
England

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                  Conservation DistList Instance 9:66
                  Distributed: Monday, March 25, 1996
                        Message Id: cdl-9-66-009
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