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"[...]darkened. "Does he expect us to believe this?" one man whispered to another. "Well, you know what liars travelers are," someone else added. Finally the host spoke up, slightly embarrassed and slightly indignant. "If this is your idea of a joke," he began, but was interrupted by the surprised traveler. "Why, it's no joke at all. People fly all the time." "I am sorry that you so much underestimate the intelligence and learning of your audience," said a professor across the table. "That a person could enter some metal device-like a car with fins-and rise into the air, and be sustained there, and move forward, why that clearly violates everything we know about the law of gravity and the laws of physics. If we have learned anything from a thousand years of study of the natural world, it is that an object heavier than air must return immediately to earth when it is tossed into the sky." "Hear, hear," two or three people muttered. "Now, if you perhaps mean that these 'airplanes,' as you call them, are somehow flung into the air for a short distance and then fall to the ground, well,[...]".