George III Inlaid Mahogany Zograscope Circa. 1790. 62 cms. High.
The Zograscope is an optical device for magnifying flat pictures that also has the property of enhancing the sense of the depth shown in the picture. It consists of a magnifying lens through which the picture is viewed. This example has the lens mounted on a stand in front of an angled mirror which allows the viewer to sit at a table and to look through the lens at the picture flat on the table. An engraving made for this purpose, typically with extensive graphical perspective is called a vue d'optique or "perspective view".