Stereoscopes 'Gaumont' (various)

a great compilation of three fine Gaumont stereoscopes from the 1920's, (1) very rare hand viewer for transparencies known as 'La Corollaire Gaumont', made of leather covered wood, cast aluminium eyepieces, adjustable eye base and rack and pinion focus, in good condition, (2,3) two ‘Stérédrome Métallique’ table-top viewers for 45x107 slides, one in simulated mahogany and the other one in black paint finish, the paint is original but shows some wear, the ground glass in the rear of the black viewer is missing,only one slide tray for both viewers, both in good working order. (3)