Stereoscope cards
A stereoscope is a device for viewing a stereoscopic pair of separate images, depicting left-eye and right-eye views of the same scene, as a single three-dimensional image.Stereoscopes, which were first produced in the 1850s, consisted of two prismatic lenses and a wooden stand to hold the stereo card.
In 1861 Oliver Wendell Holmes created and deliberately did not patent a handheld, economical viewer. His type of stereoscope remained in production for a century.
See links below for some sample cards providing photographic images of the first world war and an article about this important series of pictures.
- Photographing the Great WarArticle about the series of Stereocards (samples at link above) depicting the Great War in photographs.