“I was drawn into the history of “cold” light—luminescence—which started perhaps before there was any language to record things, with observations of fireflies and glowworms and phosphorescent seas; of will-o’-the-wisps, those strange, wandering, faint globes of light that would, in legend, lure travelers to their doom. And of Saint Elmo’s fire, the eerie luminous discharges that could stream in stormy weather from a ship’s masts, giving its sailors a feeling of bewitchment. There were the auroras, the Northern and Southern Lights, with their curtains of color shimmering high in the sky. A sense of the uncanny, the mysterious, seemed to inhere in these phenomena of cold light—as opposed to the comforting familiarity of fire and warm light.”

—Oliver Sacks, Uncle Tungsten: Memories of a Chemical Boyhood, 2001.