Image on reverse of painting support

I am currently researching the possible causes of a recently
observed phenomena. Three textile supported paintings have come into
the conservation department recently which display transfer images
on the reverse--something my colleagues and I have never observed
before.

The images are monotone but have positive correlation and are direct
transfers from the images on the front. They are all late 19th/early
20th century and are portraits. Has anyone observed this?

I am considering that it may have something to do with techniques
developed at this time to photosensitize textiles, any information
anyone has on these techniques (apart form the very useful article
by Mervyn Ruggles from JAIC 1985) would also be gratefully received

Anne Bacon


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                  Conservation DistList Instance 18:53
                  Distributed: Saturday, May 14, 2005
                       Message Id: cdl-18-53-026
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