Prismatic-square-type

Period: 1850–1890 / 1890–1930    Tag: Glossary

The prismatic-square-type stereoscope is an unofficial term for a box-type stereoscope that emerged in the 1850s and was made with almost identical characteristics by several manufacturers in the United Kingdom and France. In the Negretti & Zambra catalogue, the type is called a Cosmoramic stereoscope; other sources use a more general designation, such as box pattern.

The main characteristic is the use of prismatic lenses. The stereoscope contains two square prismatic lenses mounted in a lens panel. The lenses are surrounded by square openings with rounded corners. The lens panel can sometimes be opened to clean the lenses. The form of the stereoscope’s body corresponds to that of Brewster-type stereoscopes from the 1850s.

Related items:
Box-type stereoscope  Brewster-type stereoscope  Negretti & Zambra  Prismatic lens