Wooden box with flip-top lid, set of eyeholes on either side, turning knobs on opposite sides.
Willie and Tad Lincoln were the envy of their friends when they received this stereoscope (similar to a modern ViewMaster). They could put special photographic cards into a holder inside and see the image in 3-D. Favorite images were Niagra Falls and the Taj Mahal.
You are all set!
Your first Culture Weekly will arrive this week.