Museum of Interesting Things’ Daniels calls stereoscopes, also known as steropticons, as the Google and YouTube of the 1800s. Used up until the early 1900s, you could buy a pack of cards with a certain theme, ranging from kid's cartoons to teaching aids, medical devices and places around the world, for your stereoscope. The front of each card had a photo, while the back had text teaching you all about what you were viewing.
“In the 1800s, it was expensive to go to New York or France. Books were expensive. Libraries weren’t everywhere. So what did you do if you wanted to Google something? … You’d get these stereoscope slides and buy them in packs of 25. Learn about the Civil War, France, put in a slide, take out a slide, put in another slide, take out a slide--that’s your YouTube,” Daniels said.