Spider web as painting support

Recently I received a 19th-century watercolor (Germany,Tyrolia) for
conservation. The painting support is a spider web. This web layer
is a product of the silk spider, scientific name "Araingee nephila".
The painter's name is Burgmann Johann (circa 1825). This information
I received from Dr. Helmut Bansa (Thieme-Becker Lexikon), the editor
of Restaurator.  Does anyone have more information concerning this
type of painting on spider web or about the techniques of it? I will
appreciate any relevant information,

Michael Maggen
Senior Paper conservator
Israel museum

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                  Conservation DistList Instance 10:51
               Distributed: Wednesday, November 27, 1996
                       Message Id: cdl-10-51-007
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