Theft detection devices

We are looking for theft detection devices (devices/products that will
trigger an alarm if someone attempts to steal something) that can be
used for materials with artifactual value.  We use tattle tape on our
circulating collections, but this is not appropriate for our special
materials.  We have found that even if we lay pieces of tattle tape
inside books (without sticking them into the books) the adhesive tends
to ooze out over time.

The literature is full of ways to apply ownership marks to materials
with artifactual value, but I haven't found much about theft detection
devices.

I have heard about an invisible spray that will set off an alarm.  I
would imagine that something in the spray is magnetically sensitive and
therefore I am very concerned about using it on our materials.  Does
anyone know about or use this spray?

Finally, if you are not currently using theft detection devices on your
materials with artifactual value, I am interested in finding out about
other theft detection measures that you are taking for these materials.

Caroline Gilderson-Duwe
Preservation Dept.
Golda Meir Library
University of Wisconsin-Milwaukee
414-229-6726
Fax: 414-229-6791

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                  Conservation DistList Instance 8:38
                 Distributed: Sunday, November 20, 1994
                        Message Id: cdl-8-38-015
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