Picture the posture: a person bent forward over a wooden cabinet, hands on the rim, one eye down at a small window, and inside, a lit strip of perforated film hurrying past a shutter. Perhaps twenty seconds of it. Then straighten up, blink at the room, and let the next person have a turn. On this day in 1897, Thomas Edison was granted the patent for that machine, the Kinetoscope, the peephole viewer that came before anything was thrown up onto a wall.

Edison had sketched the idea in words back in 1888, but the years of actual building fell largely to William Kennedy Laurie Dickson and the team at the New Jersey lab, between roughly 1889 and 1892. They also had to make the camera to feed it, the Kinetograph, which moved film in stops and starts fast enough to catch motion. Crews rarely get the patent. They generally get the work.

What interests me is the arithmetic of the audience. One. No neighbour laughing half a beat before you, no shifting of coats in the row behind, no shared held breath. The illusion was already complete in 1897; the audience hadn't been invented yet. I have spent twenty-six years watching a room decide together when to lean in. Somebody, on some afternoon in a parlour, did all that leaning alone.