Corrective Calisthenics Stereoview c1930 Keystone Stereoscopic Treatment A1223 For Sale

\"Left Hyper-esophoria Corrective Calisthenics\"

Published by Keystone View Company, formerly one of the largest stereoview publishers in the world.

This is a stereoview (also known as a stereograph or stereoscope card). It was one of the first forms of 3D photography. The images were captured with a special stereoscopic camera, which had two lenses - simulating the view of our left and right eyes. The two, nearly identical pictures were then mounted next to each other (most commonly on a piece of cardstock, glued on as photographs or printed as lithographs). The image could then be seen in three dimensions when viewed through a device known as a stereoscope, stereopticon, and/or televiewer.

Standard-size stereograph, measuring about 3.5 x 7 inches.

Will be shipped safely and securely! All of my paper items are protected in archival-safe polypropylene sleeves and packaged in rigged cardboard.