1888, 10 February
Patent No: 362,390: Morgan's Improved Multiplex Photographic Background Frame (detail)

Magazine illustration
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G.W. Morgan had patents in Great Britain, France and America. Patent No: 362,390, Patented May 3, 1887.
 
It is described in a letter to the editor in "Background Arrangements" by G.W. Morgan in "The Photographic News", Volume XXXII, February 10, 1888, p.92
 
For the original patent Multiplex Photographic Background, (US362390A)
 
LL/34554