Smithsonian Institution, Washington, D.C. (ca. 1874). 
During the latter half of the 19th Century, stereopticon views were all the rage — and many of them were views of paleontological exhibits. To see these images of Benjamin Waterhouse Hawkins Hadrosaurus in three dimensions, just “reverse cross” your eyes.
Smithsonian Institution (late 1870s).
Smithsonian Institution (late 1870s).
Academy of Natural Sciences, Philadelphia, PA (1876).
Academy of Natural Sciences (ca. 1876).
Smithsonian Institution (late 1870s).
E. M. Geological Museum, College of New Jersey, Princeton (ca. 1876).
