Deterioration of glass negatives

Eli Echols <eaechols [at] newchurch__edu> writes

>At the Raymond and Mildred Pitcairn Archives in Bryn Athyn,
>Pennsylvania, we have a collection of about 4000 Glass Negatives. We
>are only just beginning to address their preservation appropriately,
>and in doing so I have noticed that many of them smell pretty
>strongly of vinegar.

I have come across "glass" slides before that had the vinegar smell.
On investigation it became clear that an acetate transparency was
sandwiched between two sheets of glass with tape around the edges to
hold it all together.

Carolyn Murphy
Conservator (Works on paper)


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                  Conservation DistList Instance 14:27
                 Distributed: Friday, November 10, 2000
                       Message Id: cdl-14-27-005
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