We were born into a world of electric illumination. Incandescent lights, fluorescent lights, halogen, xenon, LEDs. It glows from lamps and televisions, twinkles from nightlights, puts on a show when you rush past it in tunnels, speckles a cityscape at night. We take it for granted, generally speaking. It’s tough to imagine a world in which electric light does not exist. But, when you think about it, electric lamps have only been the norm for a tiny,TINY percentage of the history of human life.