Usage conditions apply
The zogroscope was designed to magnify prints so they could be seen more easily. It has a convex lens mounted in a square wooden frame that, in turn, is supported on a pedestal. A second frame, hinged at the top, holds a mirror that can be held out at any desired angle. The form came into use in the eighteenth century and remained popular throughout the nineteenth century. It was also known as an optical diagonal machine or cosmorama.
Ref: J. A. Caldecott, “The Zogroscope or Optical Diagonal Machine,” Annals of Science 9 (1953): 315-322.
Currently not on view
Object Name
optical diagonal machine
Physical Description
wood (overall material)
glass (overall material)
overall: 63 cm x 31.3 cm x 22 cm; 24 13/16 in x 12 5/16 in x 8 11/16 in
overall: 25 in x 12 in x 8 in; 63.5 cm x 30.48 cm x 20.32 cm
ID Number
catalog number
accession number
Credit Line
University of Virginia
Science & Scientific Instruments
See more items in
Medicine and Science: Physical Sciences
Science & Mathematics
Data Source
National Museum of American History
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