The Great Johnstown Flood. Ruins of Johnstown, Pa. Stereoscope card.

Pennsylvania stereoscopic card.

Robert Dennis's stereographs collection includes more than 72,000 stereoscopic views organized primarily by geography. The collection bears the name of the native New Yorker who assembled it over a period of more than six decades, Robert N. Dennis (1900-1983).

Stereographs consist of two nearly identical photographs or photomechanical prints, paired to produce the illusion of a single three-dimensional image, usually when viewed through a stereoscope. Stereographs were produced from the 1850s to the 1940s, with the bulk between 1870 and 1920.

pennsylvania johnstown pa webster albee publisher stereoscopic views ruins johnstown united states robert dennis collection of stereoscopic views 19th century history of pennsylvania ultra high resolution high resolution nypl

1889 - 1889

New York Public Library

https://digitalcollections.nypl.org/

Creative Commons CC0 1.0 Universal Public Domain Dedication ("CCO 1.0 Dedication")