Glass slides

I am restoring some glass theatre slides for the American Museum of
the Moving Image and I'm wondering how the images were made. They do
not look like photo emulsions, nor do they look handpainted. Does
anyone know how they were made? It looks like they might be
lithographs but I'm not sure. I'm concerned that the images might be
soluble in Hextal and would rather not used solvents to test them.

Susan White
White Conservation Services, NYC

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                  Conservation DistList Instance 16:56
                  Distributed: Monday, March 31, 2003
                       Message Id: cdl-16-56-010
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