Will visiting an historic mansion we lucked out – they also had a small display of historical stereoscopes. These are pictures that were printed on a card with separate left eye and right eye views, and then viewed with a stereoscopic viewer.
The ones we saw were probably a good 100 years old – pretty cool! I took 3D stereoscopic pictures of the viewers and will eventually post those here.
Amusingly, very little has changed in 100 years – apparently 100 years ago, people liked looking at 3D images of cute cats. Just an early version of Youtube, we guess!