Watermarks

We are trying to find and record any watermarks present on a large
(7 foot) 16th century cartoon.  There are no watermarks or chain
lines visible using transmitted light because the paper support is
varnished and then mounted onto paper and canvas secondary supports.
Now we are looking into other methods of examination.

I would like to hear about other people's experiences using a low
rad portable x-ray machine to record watermarks on paper.  Is this
useful, and do you have any tips to share?  Does anyone have any
other favorite techniques to detect and record elusive watermarks?

As well, has anyone had experience looking for watermarks on papers
that are mounted to paper and canvas?


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                  Conservation DistList Instance 16:8
                 Distributed: Wednesday, July 24, 2002
                        Message Id: cdl-16-8-013
                                  ***