1865 Albumen / Tissue stereograph of the Norte Dame Cathedral in Paris, France (left eye view). Stay tuned for the JUNE 2019 lecture / web page (now in place): "1800's Stereographs Reveal Early U.S. Christian Life in 3-D".
While most of the stereo view cards of the late 19th / early 20th century had typical "popular" culture content, there existed a small coterie of stereo photographs that went around and documented Christian living.
It is my collection of these specific stereographs that sets it apart from the rest ... including those collections held by academic institutions.
My impression is that they were passed over as a "novelty" ... and not taken as seriosuly as more traditional photographs of the period. That is a shame because, when comparing 2D photos to 3D stereographs, the stereographs just come to life.
However, the lack of interest helped me over the years, because it made them less sought after ... and, therefore, less expensive to own.