Photo-fluorography Stereoscope
Ref. J7
Of unknown make, this stereoscope was donated to me in the sixties when its previous owner, a local hospital, had no use for it.
The table-top stereoscope is strongly built, with a tilting body. The lighting, behind the blue tinted ground glass, is by two small size 40 Watt incandescent light bulbs, with an adjusting knob on the metal base for the light intensity. Heat dissipation is through the eight small openings on the rear of the body.
The optical viewing system for each eye consists of a low power convex lens, combined to a very low grade prism in order to ease the strain on the eye muscles from the effort of convergence while viewing.