Stereoscope ‚Le Corollaire‘

Gau­mon­t’s patent for the Stéréo­scope Corol­laire (French Patent FR319,-219) pro­vides sev­er­al details about the con­struc­tion of the instru­ment. It incor­po­rates a mov­able car­riage on which the eye­piece assem­blies are mount­ed. This car­riage is guid­ed with­in the body of the stere­o­scope by rack-and-pin­ion rods that engage with tubes locat­ed in the low­er part of the instru­ment. The car­riage is moved for­ward or back­ward by means of a knurled adjust­ment knob that dri­ves the rack-and-pin­ion mech­a­nism. The mounts of each objec­tive lens are inde­pen­dent­ly adjustable, allow­ing the inter­pupil­lary dis­tance to be set. This arrange­ment was specif­i­cal­ly designed to be par­tic­u­lar­ly well suit­ed for short-focus lenses.
(from: Moulin­ier et al. His­toires de vision­neuses stéréo­scopiques français­es. Limo­ges, 2025, p. 61. Author’s translation.)