Interleaving

I am writing to ask advice on interleaving a very large and valuable
volume of 100 hand-colored engravings dating from the 1830s.
Particularly with some of the darker, larger images,  there is a
fair amount of offsetting onto the preceding plate.

The binding is the original, and no guard sheets were bound in.
Interleaving even with tissue distorts the volume so that there is a
gap of about an inch between the plates and the fore-edge of the top
board (the volume is stored flat due to its size), which seems to
put an unacceptable strain on the hinge, because the board is quite
heavy.

What is the best way to protect both the plates and the binding?
Should I go ahead and interleave, and then build a custom-made
triangular support from acid-free mat board to relieve the strain on
the binding?  Or would some other procedure be preferable?

Elaine Smyth
Curator of Rare Books & the E.A. McIlhenny Natural
    History Collection
LSU Libraries
Louisiana State University
Baton Rouge, LA 70803-3300

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                  Conservation DistList Instance 9:52
                  Distributed: Sunday, January 7, 1996
                        Message Id: cdl-9-52-015
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