claude lorraine glass

from The Collaborative International Dictionary of English v.0.48
Claude Lorraine glass \Claude" Lor*raine" glass`\ [Its name is
   supposed to be derived from the similarity of the effects it
   gives to those of a picture by Claude Lorrain (often written
   Lorraine).]
   A slightly convex mirror, commonly of black glass, used as a
   toy for viewing the reflected landscape.
   [1913 Webster]
    

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