Stereoscope, Box-sliding with Eyecups

This stere­o­scope is attrib­uted to Mat­tey, although the attri­bu­tion can­not be con­firmed with cer­tain­ty. While its over­all design close­ly resem­bles known Mat­tey prod­ucts, the focus­ing knobs are made entire­ly of nick­el-plat­ed met­al rather than the Bake­lite knobs more com­mon­ly found on the com­pa­ny’s stere­o­scopes. This unusu­al fea­ture makes a pre­cise dat­ing difficult.
Unlike most Mat­tey hand-held stere­o­scopes, which focus by extend­ing the lens tubes, this mod­el employs a box-slid­ing mech­a­nism described in the com­pa­ny’s cat­a­logues as mise au point à tiroir. The unusu­al con­struc­tion results in a com­par­a­tive­ly large body for a hand-held stere­o­scope (see last image).

Fur­ther read­ing: Stere­oscopy His­to­ry Series — Mat­tey (A. Ruiter)