Removing photograph from glass

A note of caution on removing photographs from glass by immersion in
water--the damage is almost always caused by moisture (liquid water or
high humidity) in the first place.  In photographs with gelatin
emulsions, which are the contemporary black-and-white prints mentioned
in the previous submission, it is common for the gelatin to have
deteriorated in the area of adhesion or overall.  As a consequence, the
swelling and solubility of the gelatin in water will have increased,
often so much that it will dissolve with immersion. The presence of mold
compounds this problem.  The condition of the photograph and spot
testing will give clues to the conservator about whether removal from
the glass can be safely undertaken and/or is likely to succeed.  I have
found that separation of the glass and gelatin emulsion is most easily
and safely done with the local application of moisture, rather than
immersion.

Barbara Lemmen
Photograph Conservator
13 Farman Avenue
W. Lebanon, N.H.  03784
603-298-6071

                                  ***
                  Conservation DistList Instance 8:63
                 Distributed: Sunday, February 12, 1995
                        Message Id: cdl-8-63-006
                                  ***