Flame and filament

One of man's greatest inventions was also one of his most modest: the wick. We don’t know who first realized, many thousands of years ago, that fire could be isolated at the tip of a twisted piece of cloth and steadily fed, through capillary action, by a reservoir of wax or oil, but the discovery was, as Wolfgang Schivelbusch writes in Disenchanted Night, “as revolutionary in the development of artificial lighting as the wheel in the history of transport.” The wick tamed fire, allowing it to be used with a precision and an efficiency far beyond what was possible with a wooden torch or a bundle of twigs. In the process, it helped domesticate us as well. It’s hard to imagine civilization progressing to where it is today by torchlight. The wick also proved an amazingly hardy creation. It remained the dominant lighting technology all the way to the nineteenth century, when it was replaced first by the wickless gas lamp and then, more decisively, by Edison’s electricity-fueled incandescent bulb with its glowing metal filament. Cleaner, safer, and even more efficient than the flame it replaced, the light bulb was welcomed into homes and offices around the world. But along...