Identifying electrical insulation material

I have an X-ray machine that dates to about 1917.  There is a metal
bar that carries electricity from the high voltage transformer coil
to the X-ray tube.  The insulation material appears to be multiple
layers of cellophane.  It is a thin clear plastic.

Any experts on early twentieth century electronics able to identify
the material used for insulation?

Alan Hawk
Collections Manager
Historical Collections National Museum of Health and Medicine
Armed Forces Institute of Pathology
Bldg. 54, Walter Reed Army Medical Center
Washington DC 20306-6000
202-782-2205, DSN 662-2205
Fax: 202-782-3573, DSN 662-3573


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                  Conservation DistList Instance 21:14
                   Distributed: Tuesday, July 3, 2007
                       Message Id: cdl-21-14-018
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