I bought them at a consignment shop this winter: a stereoscope viewer and a set of 21 card-mounted stereographs in a worn slipcase. Published around 1909, the cards showed views of Jerusalem. The contraption felt like a wood-and-metal prototype VR headset, and indeed it was with stereoscopes that 3D imaging was born in the mid-19th century.

So popular were stereoscopes in the US that many were sold door-to-door, and not just as entertainment but as education. The publishers of this set of Jerusalem images, Keystone View Company, was the largest US stereoscope producer. It employed photographers and published thousands of views of towns, cities, monuments, wonders and curiosities around the world. One of Keystone’s selling points was its extensive explanations of the images, touching on history, geography, peoples and culture. In this stereograph, we see the imposing stonemasonry of old Jerusalem’s Jaffa Gate, but perhaps most interesting now are the parked carriages and the routine procession of people and horses. This makes its era relatable to our eyes. We see also the unidentified man at lower right: As an editor interested in relationships among those who make and publish images and those who appear in them, I wonder, was he asked to sit there? Was he an assistant to the photographer? A porter for equipment? Or was he, like us, just curious about a pair of lenses peering out from a box, eyes of a new technology that would, over the next century, become what we call “virtual reality”?

—Richard Doughty