Antique Manual Stereoscope with Various Stereoscopic Crystals from the 1920's. Small wooden stereoscope in perfect condition with different photographs from ca. 1920. The apparatus appears perfectly distributed in a nice and simple wooden case with space for the photographs and to guard the chamois, necessary to clean the lens. Wooden case, in perfect condition, with mirror on the inside, and with a decorative lock of vegetal shapes, which attaches the original key. There are 12 photographs of 107 X 45 mm, which can be seen in the mirror and 42 additional photos of 130 X 60 mm, all of them in perfect condition. As for the mechanics of the machine, it is overhauled and in perfect condition. The only thing the spectator has to do is to enjoy the 3D images. The stereoscope, understood as a device that presents a double image that is mixed in our brain as a single stereoscopic image, was invented by Sir Charles Wheatstone in 1840. It is a very simple device in essence, consisting of four small mirrors, placed in such a way as to deflect the images corresponding to each eye, placed side by side, which, when viewed mounted one on top of the other, give a stereoscopic or three-dimensional effect. The main advantage on the part of the viewers with this apparatus is that, as there is no glare reduction, the images can be presented in very high resolution and in full spectrum color. The images are presented directly to the eyes and thus to the visual center of the brain, feel like you are stepping into another era with this magnificent device! Dimensions: Stereoscope: 13.1 x 11 x 7 cm (excluding lenses); Case: 27 x 21 x 9 x 9 cm.