Pseudoscope, made by C. D. Ahrens, London, England, c. 1850. Consists of brass supporting stand with small leather case containing two stamped metal discs and cylindrical eyepiece unit Pseudoscope, made by C. D. Ahrens 1845-1855
Pseudoscope viewer. Wooden panel bearing two brass eyepieces fitted with lenses and reversing prisms. Lever adjusts prism separation. Each eyepiece rotates. Slot in panel and marks on front indicate handle or stand fitted. Gives pseudoscopic effect on standard stereocards. Inscription partially illegible "Brevete ..." Pseudoscope Viewer