Coal mine opening. 19th century Pennsylvania 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.

Пенсильвания mauch chunk pa угольная шахта высокое разрешение стереоскопические виды каменный уголь мой Соединенные Штаты лиловый кусок Роберт Деннис коллекция стереоскопических изображений 19 век история Пенсильвании промышленная история угольные шахты и горнодобывающая промышленность горнодобывающая индустрия публичная библиотека Нью-Йорка

1858 - 1900

New York Public Library

http://digitalcollections.nypl.org/

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