617834 Stereoscopic card depicting a photographer viewing through a stereoview above 5th Avenue, New York, c.1900 (sepia photo) (see also 617884) by Underwood & Underwood (c.1881-1940); Private Collection; (add.info.: Stereoscopic cards were popular from c.1850 until the early 20th century and consisted of two photographs. mounted on board and were viewed through a stereoscope to give a 3D image;); Prismatic Pictures ; American, out of copyright.