There are plenty of places around the globe where people have no access to heavy machinery, but do know how to deal with wind, sailing and basic mechanical principles. The experiments might even have practical uses nowadays. And other ancient civilisations certainly knew about kites as early as 1250 BC, the Chinese were using them to deliver messages and dump flaming debris on their foes. Although it dates from several hundred years after the building of the pyramids, its sophistication suggests that the Egyptians might nave been developing ideas of flight for a long time. A wooden artefact found on the step pyramid at Saqqara looks uncannily like a modern glider. In addition, there is some physical evidence that the ancient Egyptians were interested in flight. And they are known to have used wooden pulleys, which could have been made strong enough to bear the weight of massive blocks of stone. Harnessing the wind would not have been a problem for accomplished sailors like the Egyptians. Others feel there is more of a case for the theory. The evidence for kitelifting is non-existent,' says Willeke Wendrich, an associate professor of Egyptology at the University of California, Los Angeles. Indeed, the experiments have left many specialists unconvinced. The evidence for using kites to move large stones is no better or worse than the evidence for the brute force method,' Gharib says. There are no pictures showing the construction of the pyramids, so there is no way to tell what really happened. 'Whether they actually did is another matter,' Gharib says. So Clemmons was right: the pyramid, builders could have used kites to lift massive stones into place. This jerk meant that kites could lift huge weights, Gharib realised. Even a 300-tonne column could have been lifted to the vertical with 40 or so men and four or five sails. There was a huge initial force - five times larger than the steady state force,' Gharib says. What they had failed to reckon with was what happened when the kite was opened. The wind was blowing at a gentle 16 to 20 kilometres an hour, little more than half what they thought would be needed. The instant the sail opened into the wind, a huge force was generated and the column was raised to the vertical in a mere 40 seconds.' 'We were absolutely stunned,' Gharib says. The kite lifted the column clean off the ground. The idea was that as one end of the column rose, the base would roll across the ground on a trolley.Įarlier this year, the team put Clemmons's unlikely theory to the test, using a 40-square-metre rectangular nylon sail. So they rigged up a tent-shaped scaffold directly above the tip of the horizontal column, with pulleys suspended from the scaffold's apex. The key was to use a pulley system that would magnify the applied force. Even a modest force, if sustained over a long time, would do. Their initial calculations and scale-model wind-tunnel experiments convinced them they wouldn't need a strong wind to lift the 33.5-tonne column. Gharib and Graff set themselves the task of raising a 4.5-metre stone column from horizontal to vertical, using no source of energy except the wind. And since he needed a summer project for his student Emilio Graff, investigating the possibility of using kites as heavy lifters seemed like a good idea. The possibility certainly existed that it was a kite/ he says. The object in the sky apparently had wings far too short and wide for a bird. He too was puzzled by the picture that had sparked Clemmons's interest. 'Coming from Iran, I have a keen interest in Middle Eastern science/ he says. Intrigued, Clemmons contacted Morteza Gharib, aeronautics professor at the California Institute of Technology. She wondered if perhaps the bird was actually a giant kite, and the men were using it to lift a heavy object. They were holding what looked like ropes that led, via some kina of mechanical system, to a giant bird in the sky. While perusing a book on the monuments of Egypt, she noticed a hieroglyph that showed a row of men standing in odd postures. Now a Californian software consultant called Maureen Clemmons has suggested that kites might have been involved. But there is no evidence to back this up. The conventional picture is that tens of thousands of slaves dragged stones on sledges. The pyramids of Egypt were built more than three thousand years ago, and no one knows how. Marcus Chown reckons the answer could be 'hanging in the air'. No one knows exactly how the pyramids were built.
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