Later, at Detroit airport, the tiniest thing - in a cafe, a man saw another customer's suit-bag flop onto the ground at a nearby table, into the path of oncoming travellers and their wheelie bags.

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Power is generated by the wing flying in a circular path, with electricity transmitted to the ground via the conducting core of the tether.

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The giant ferns and trees of prehistory crowded in on a silver path that hovered six inches above the ground.

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Ground squirrels scampered under the boardwalk part of the path, and our dog, Tigra strained at the leash.

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Then, they reach a parking area and take a quarter-mile-long path toward the mountains that leads to a couple of acres of ground enclosed by an eight-foot chain-link fence.

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Here's how it goes: A group of runners (aka pack of hounds) looks for clues (dashes of flour or chalk marks) on the ground to indicate the correct path.

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