A New Yorker was travelling in Louisiana around Christmas time. In a small town square he admired a nativity scene but was puzzled by one thing: the three wise men were wearing firemen's helmets. Unable to work out why, he decided to ask the old woman who worked at the store. "Excuse me, ma'am," he said. "I'm not from these parts, and I don't understand why the three wise men are wearing firemen's helmets." She snarled: "You damn Yankees, you never read your Bibles!" "I do," he protested, "but I…