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Just a follow-on from the discussion on original labels: it's a axiom of conservation work that you should never use a glue if you don't have to. If there's a purely mechanical way to fasten two things together (like string or an attached Mylar envelope) that
should always be used. Even "reversible" glues like Paraloid (Acryloid) B-72 will bind fibers and cause distortions through differential shrink rates that can't be "reversed".</div>
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A glue story: I just spent several weeks detaching all the labels, letters, invoices and other bits of paper that had been glued into our collection ledgers over the 100-plus years of their use, before sending the books off for scanning. From the 1890s up until
about 1935, our folks used a remarkably "reversible" natural resin of some kind that still dissolves in water from a hard, glass-like state to a sticky solution; adding more water thins it further, allowing even tissue-thin notes to be safely peeled off the
underlying page.<br>
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Thereafter, however, we switched to some form of synthetic glue that is much harder to remove, requiring acetone and thus a fume hood. Not progress, then...</div>
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<div style="font-family:Tahoma; font-size:13px"><b>Paul Callomon</b><br>
<i>Collection Manager, Malacology and General Invertebrates</i><br>
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<font face="Verdana"><b>Academy of Natural Sciences of Drexel University, Philadelphia</b></font><br>
<i>callomon@ansp.org Tel 215-405-5096 - Fax 215-299-1170</i><br>
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