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Secrets of Lost Empires: A "Nova" Special Presentation

Medieval Siege (#101)

The trebuchet, a missile thrower invented in China more than 2,000 years ago, played a central role in siege warfare in Asia, the Middle East and Europe. Yet surprisingly little is known about how the various forms of this ancient weapon were built. The last remaining example from medieval times was dismantled for firewood a century ago, and the surviving descriptions and drawings are fragmentary and ambiguous. In this program, two teams made up of timber framers, engineers, military historians and experts on siege weapons attempt to build a trebuchet capable of the prodigious feats claimed for the medieval engines of war. Along the shores of Scotland's Loch Ness, at Urquhart Castle, the episode explores how the evolution of siege weapons influenced castle design and paints a vidid picture of life under siege in the time of Edward I. [56 minutes] Closed Captioning

This episode has not aired in the past few months on Iowa Public Television.

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Series Description: Following the blueprint established in SECRETS OF LOST EMPIRES - an archaeology series that eschewed talking heads and inert artifacts - the second series follows teams of living, breathing, passionate, inquisitive people as they struggle to duplicate the technological feats of ancient civilizations, using the tools and materials available in antiquity.

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  • Pharaoh's Obelisk (#102)

    In the original SECRETS OF LOST EMPIRES, a team of experts, working with a precut obelisk 43 feet tall, learned how to lash it to a sled and move its 40 tons with the help of lubricants and log rollers. They succeeded in coaxing it down an incline until one edge rested in the turning groove that allows each obelisk to be hinged up onto its pedestal. However, limited by time and budget, they were unable to lever or pull the great stone upright. It rests today at a 40-degree angle, just where they left it three years ago. Now, they return to Egypt to make a second attempt and to tackle the equally formidable challenge of discovering how the ancient Egyptians transported their finished obelisks more than 100 miles to sites like the Great Temple of Amun-Re outside Luxor. [56 minutes]

  • Easter Island (#103)

    The statues of Easter Island are an archaeological enigma. The haunting human figures, carved in stone, are considered the greatest sculptural achievement in all of Polynesia. Yet they're found in one of the most isolated places on Earth, a speck of land in the middle of the Pacific, almost 1,500 miles from the nearest inhabited land. Nearly 1,000 of the moai dot the Rapa Nui landscape, all that remains of a civilization that flourished there for more than a thousand years. Who carved the statues? Where did they come from and how did they reach this barren outpost? What did the statues mean to them? And why did the civilization die out? These are some of the questions that have fascinated westerners ever since a Dutch sea captain saw them on Easter Sunday, 1722. [56 minutes]

  • Roman Bath (#104)

    Many of the engineering principles and building techniques that underlay the great public works of the Roman Empire - thousands of miles of stone-paved highways, huge bridges that used the arch (a Roman invention) to span deep ravines and aqueducts that delivered fresh water to city centers from hundreds of miles away -- were first tested in a structure for which Rome's engineers are remembered today: the Roman bath. In its vaulted ceiling, its use of the revolutionary new building material now called concrete, and its remarkably intricate systems for plumbing and heating, each bathhouse embodied in microcosm the Romans' engineering genius. Still, despite the cultural and architectural importance of the Roman bath, many of its workings are still poorly understood. What mixture of sand, lime, water and rubble did the builders use to make their watertight concrete? How did they design and cast the domes and vaulted ceilings that allowed them to create large, open interior spaces? And how did they create the intricate plumbing and heating systems responsible for the baths' legendary comfort? [56 minutes]

  • China Bridge (#105)

    An ancient Chinese bridge, the Rainbow Bridge, baffles today's engineers and scholars of Chinese history. Evidence of its existence is found only in paintings and in a description from a Song Dynasty historian. The bridge is neither an arch nor a beam, but rather a delicate hybrid of the two. How was it built? There are no technical documents or records that describe the process, nor are there any extant examples of a Rainbow Bridge. Based on scant historical information and a close analysis of the 12th-century painting Going Up the River During the Qingming Festival - a depiction of life in the Song Dynasty capital of Kaifeng around 1000 A.D. - Professor Tang Huan Cheng and a team of experts recreate the bridge. Working in a lively village in the picturesque Yellow Mountains of central China's Anhui Province, two teams work from opposing banks, each with a different set of challenges. Their final act will be to join the middle section of the bridge. [56 minutes]

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