The Smith, Beck & Beck book stereoscope is based on Joseph Beck’s patent of 1859. It’s designed for viewing stereocards and stereoscopic images that are mounted in a book. The stereoscope was very successful and around 3000 devices were produced until c.1890. It’s probably the most complete book stereoscope ever produced.
The two prismatic achromatic lenses can be focussed and may be rotated to adjust for stereoscopic images of various sizes. The left lens of my viewer has the inscription R & J Beck, which indicates that it’s manufactured between 1865 and 1890. There is a frosted glass between the lenses and the baseplate has a mirror to reflect light.
The end of the viewer has two small clamps that can be used to mount a stereocard. The clamps can be turned away when the viewer is used to rest directly upon a stereoscopic image that’s mounted in a book. The bottom contains a handgrip with the text Patent Mirror 2026.
David Starkman has written an excellent article on the history of books with stereoscopic images and book stereoscopes: An Abbreviated History of Stereo-Pair Illustrated books.
- Wing, Paul. Stereoscopes, the first one hundred years, 1996