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Ever since someone in a saber-toothed-tiger pelt figured out that a piece of burning forest carried back home would keep the cave bear at bay, we humans seem to have been programmed to gather around a fire. But our forebears, from pragmatic cave dwellers to no-nonsense Colonials, would probably roll their eyes at modern romantic notions about a burning pile of logs. Precisely because flames are no longer a daily necessity, they seem all the more alluring — especially in this season when a warm fire offers some compensation for the early dark.