"Secrets of Lost Empires: Pharaoh's Obelisk"
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NARRATOR: Egypt is littered with fantastic ruins, all created to preserve Pharaoh's name and glorify the ancient gods. For nearly 2,000 years, ancient builders were pushed to their limits to create the most dramatic, the most impressive temples and palaces ever known. Perhaps the most difficult challenge of all was to raise an obelisk. Carved from a single piece of granite, an obelisk could rise over 100 feet, and weigh up to 500 tons. How did they do it? In 1994, a team of experts traveled to Egypt to tackle the problem. But their attempt to erect an obelisk - just a fraction of the size of the ancient ones - fell short. Tonight, NOVA returns to the land of the pharaohs. Modern engineers take another look at the evidence, and try out a radical new solution to an age-old mystery. Ropes and nerves will be strained as another team struggles to recreate the amazing deeds of an ancient empire.
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NARRATOR: 4,500 years ago, when Egypt's Old Kingdom was in its first bloom, Pharaoh was God. All the country's riches were piled into his tomb - a man-made mountain for an immortal king. But 1,000 years later, times had changed. A new god ruled the land: His name was Amun. New Kingdom pharaohs like Ramses, Thutmose and Tutankhamun still proclaimed their own divinity, yet they were all beholden to the king of gods. So they built magnificent temples to him, filled with colossal statues and giant needles of stone - the obelisks. Hieroglyphs proclaimed the pharaoh's loyalty. At the pinnacle was a small pyramid - sheathed in silver and gold. Dedicated to Amun-Ra, the sun god, the obelisks were sparkling shafts of sunlight, rendered in stone. For the pharaoh's subjects, the effect was awesome.
MARK LEHNER: It was a special effect, but they really believed in this special effect. It wasn't like Las Vegas or Hollywood. It was an effect that really happened for them.
NARRATOR: For over 25 years, archeologist Mark Lehner has been probing the meaning of Egypt's monuments. He believes that colossal statues and obelisks helped pharaoh maintain his power over the Egyptian people.
MARK LEHNER: It was a way of controlling people's perception. It was important for the pharaoh to have gigantic statues, gigantic obelisks where he mingled with the heavens. Because it was the perception of pharaoh's power at the pinnacle of society that held Egyptian civilization together.
NARRATOR: 3,500 years ago, along the banks of the Nile, monumental construction was routine. But now it seems incredible. How did Egypt manage to build so much on such a colossal scale? How could pharaoh's builders transport and erect stones weighing hundreds of tons - in an age without cranes or steel cables? A team of experts will try to solve the mystery. They have three weeks to look at the evidence and recreate the Egyptians' remarkable achievements. The first major challenge our team will face is how the ancient builders moved giant multi-ton blocks of granite. One of the most important clues was found in the tomb of an official who lived almost 4,000 years ago.
MARK LEHNER: There's one tomb scene in all of ancient Egypt, showing them transporting a colossal statue, and you see the colossal statue mounted on a sledge, being pulled over land. And there are about four lines of rope going out with teams of young men, dragging the statue along. Most of the evidence, and there is some other evidence as well, suggests that these things were pulled over land on lubricated surfaces, mounted on a sledge.
NARRATOR: To bring the ancient scene to life, stonemason Roger Hopkins joins Mark Lehner and a large Egyptian crew in an attempt to drag a 25 ton block, set on a wooden sled. Directing the effort will be Rais Abdel Aleem. The Egyptian foreman has built a roadbed with wooden timbers set into the earth. To reduce friction, the wood is smeared with animal fat. Abdel Aleem has a lot of experience moving heavy weights. But he usually relies on cranes and flatbed trucks - not dozens of men. The stone should move easily with less than 100 pullers. At least, that's what Roger hopes.
ROGER HOPKINS: I would think 75 would be sufficient, once you get that initial motion going. Once you get the block in motion, then, you know, decreases the amount of friction and it should pull right along.
NARRATOR: To break the static friction, Abdel Aleem orders the teams of men to bounce the stone with large levers. But with more than 100 pullers, the only thing moving seems to be the rope - which stretches more than anyone expected.
ROGER HOPKINS: What, did they cement this thing down? I wasn't here when they put this on the track.
NARRATOR: Part of the problem is that the men on the ropes are not pulling together.
ROGER HOPKINS: Well, we don't have a unified jerking movement to get it going quite yet.
NARRATOR: Roger decides that the men need a little extra motivation. Finally, with Roger shouting, "God is great!" in Arabic, the stone lurches forward. According to ancient accounts, the pharaohs had no problem gathering workforces that numbered in the thousands. Some were slaves, others, prisoners of war. But many were Egyptian soldiers, fulfilling their duty to their king and their god. Our crew remained enthusiastic, even though after several hours of hard work, they moved the stone only about 20 feet.
Dragging gigantic monuments is extremely slow and labor intensive. Yet the ancient Egyptians managed to transport huge obelisks and statues hundreds of miles, from granite quarries in the south, to the capital in Thebes, and further north to Memphis, and Heliopolis. Luckily, for these long journeys, the Egyptians had a unique highway at their disposal: the Nile. But for the river, Egypt would be a wasteland. The Nile's life-giving waters flow northward from the Ethiopian highlands, transforming the African desert into lush, verdant farmland. All life revolved around the river. So one form of transportation was valued above all others.
MARK LEHNER: The country of Egypt basically was the banks of the Nile. People were totally tied to the river. During the inundation season, from the middle of August to about November, the Nile valley was one big, long lake, and the villages were little islands appearing within this lake, so the only way to get about was by boat. And that meant that there were boat builders all up and down the Nile, building small fisherman's boats. There were people building medium-sized boats and yachts for noblemen. Everybody had to have a boat to get along.
NARRATOR: Thanks to the Nile, the Egyptians were early pioneers of boat construction and design. But was their nautical expertise so great that they could produce vessels strong enough to carry obelisks weighing hundreds of tons? One pharaoh left compelling evidence that they could. Her name was Hatshepsut, and she seized the throne from her young stepson around 1470 BC. One of the few women ever to rule Egypt, Hatshepsut displayed a pharaonic beard, and celebrated her reign by raising four gigantic obelisks at the Great House of Amun in Thebes. Across the Nile, at her mortuary temple, Hatshepsut bragged of transporting two of these monoliths down the river from Aswan. To help interpret the evidence, Mark welcomes on board nautical expert Owain Roberts. A lifelong sailor and boat-builder, Owain specializes in reconstructing ancient vessels.
MARK LEHNER: This is one of only two scenes that I know of that shows moving a weight of many tons by boat.
NARRATOR: On the wall of Hatshepsut's temple is a carved relief.
MARK LEHNER: We're extraordinarily fortunate to have this.
OWAIN ROBERTS: It does look rather high out of the water, doesn't she?
NARRATOR: Although much of the wall is damaged after 3,500 years, Mark and Owain can just make out an image: two obelisks lying on the deck of a boat. But how was such a vessel constructed? The Egyptians left behind some intriguing clues. Tomb and temple walls are covered with images of boats. Noblemen and kings were buried with miniature replicas of the fleets they captained in life. But perhaps the most amazing evidence was found here, at the foot of the Great Pyramid of Khufu. Zahi Hawass, Director of Giza, now oversees all excavations on the famous pyramid plateau.
ZAHI HAWASS: And this discovery, no one can believe that it can happen. It happened in the summer of 1954 that King Faisal of Saudi Arabia was visiting the pyramids, and they found there is a big mound of sand located on the south of Khufu pyramid.
NARRATOR: In 1954, one of Zahi's predecessors, Kamal el Malach, was in charge of the site.
ZAHI HAWASS: They began to clear the sand, and during that he found there are 60 large limestone blocks, each one weighed about 16 tons. Then Kamal el Malach opened a hole and he said, when he looked at the hole, he could smell history. When he did that, he smelled history from 4,600 years ago.
NARRATOR: The smell came from hundreds of planks of cedar wood, lying at the bottom of a limestone pit. The pieces fit together like a giant jigsaw puzzle. When the puzzle was complete, it looked like this. This is one of the oldest boats in the world. Built for the Pharaoh Khufu 4,500 years ago, it was carefully dismantled and buried next to his pyramid tomb, so he could use it in the afterlife. For a boat lover like Owain Roberts, it's an inspiration.
OWAIN ROBERTS: The boat is a very impressive piece of engineering. They knew all the tricks. They knew about stability of a boat. They knew about locking the timbers together to reduce movement, because movement destroys a boat. They knew about how to use rope in tension to bind the vessel together. All the tricks were known. All that restricted them was the fact that they had only wood and rope to do it with.
NARRATOR: Today, builders rely on nails. And modern boats are almost always constructed around a skeletal framework. But ancient boats like Khufu's were built skin first - by weaving together thick outer planks.
MARK LEHNER: So this is a sample of skin?
OWAIN ROBERTS: Yeah, just a sample of it, and notice how thick it is for its width, the planks are very massive.
MARK LEHNER: I notice there are holes on the edge.
NARRATOR: This is a replica of an ancient plank from Khufu's boat.
OWAIN ROBERTS: These are things they called tenons, and these tenons are knocked into place.
MARK LEHNER: So no nails?
OWAIN ROBERTS: No, not much of a hammer either, I'm afraid.
NARRATOR: The holes along the edge were made for mortise and tenon joints.
MARK LEHNER: Slowly the boat takes shape.
OWAIN ROBERTS: Yes, watch your fingers.
NARRATOR: Additional holes allowed the Egyptians to weave the planks together.
MARK LEHNER: Yep, that is pretty tight.
OWAIN ROBERTS: Get a lot of tension on there.
NARRATOR: As an extra precaution, reeds were stuffed into the seams.
MARK LEHNER: Now this is instead of caulking?
OWAIN ROBERTS: The pressure on this was one of the things that stopped the water coming in.
NARRATOR: Finally, crossbeams were added, to provide internal support.
MARK LEHNER: I see what you mean. You put on the skin first. After you build the skin, then you build the skeleton.
OWAIN ROBERTS: That's right, that's right.
MARK LEHNER: That's quite remarkable.
NARRATOR: With just wood and rope, the Egyptians created sea-going ships and barges big and strong enough to carry obelisks. But how was such a tremendous weight loaded onto a boat without tipping it over? Owain Roberts has come up with a boat design that would make the job easier.
OWAIN ROBERTS: In order to carry the weight, and to carry - have it high as in Hatshepsut's, of course we had to go for a great beam.
MARK LEHNER: Whoa, that is wide! A real wide-bodied barge.
OWAIN ROBERTS: She is indeed.
NARRATOR: To prevent capsizing, a barge capable of carrying Hatshepsut's obelisks had to be extremely wide - with a length to width ratio of perhaps two to one.
OWAIN ROBERTS: This is the way you get stability in a single hull.
NARRATOR: Owain will try out his idea on a scale model. He beaches the front end, securing it to a ramp that leads smoothly up to the deck. Ropes run from the obelisk up the ramp, across the deck and through two wooden blocks, which turn the ropes back toward the bank. In this way, the pullers can stay high and dry on the beach and don't have to wade out into the river.
MARK LEHNER: I think Owain's experiment was very successful. It's very feasible that the Egyptians simply constructed a ramp right onto one end of that boat and dragged not one, I actually think two, large obelisks onto it.
NARRATOR: After her obelisks were loaded, Hatshepsut's barge was towed downstream to Thebes and the great House of Amun, now known as Karnak Temple. Sprawling across hundreds of acres, the vast complex was expanded by a succession of pharaohs, over the course of several centuries. The god himself was believed to reside in a statue - kept under lock and key in the dark heart of the temple - the holy of holies. The statue is now gone, but ancient inscriptions describe the ritual that Amun's priests enacted within these walls.
MARK LEHNER: They would go in, and with great ritual and ceremony, they would bring out the statue of the god, they would give it a symbolic meal, they would feed the god Amun, that is to give him offerings. They would give him incense and they would bathe him ritually, they would give him clothes.
NARRATOR: Sometimes, the priest would take the statue of Amun across the Nile to the west bank of Thebes, to visit the tombs of kings and nobles.
MARK LEHNER: The family members of those deceased would be having barbecues out in front of their tombs, literally picnics, to have a communal meal with Amun and all the ancestors. All the statues of the deceased kings, who were gods in their own right, would be brought out of their temples to greet Amun. And then of course Amun would be brought back into Karnak temple, down that axis, put into his little inner house at the back part of the Karnak temple, and he would be in effect put to bed. The doors would be resealed with great ceremony and then Amun would be at rest again.
NARRATOR: As time went on, the quest to please and impress Amun drove pharaohs to erect bigger and bigger obelisks. Weighing up to 500 tons, these were some of the largest single stones ever quarried anywhere in the world. They were carved by hand and adorned with intricate hieroglyphs. Somehow, the Egyptians managed to stand them on end - without breaking them. Each balanced upon a small stone pedestal, with no support other than its own enormous weight. Only a handful of ancient obelisks survive intact in their original positions. All physical evidence of how they were raised has disappeared, except for one tantalizing clue.
MARK LEHNER: This groove is one of the only direct pieces of evidence we have as to how they actually erected the obelisks.
NARRATOR: On every pedestal stone, a deep groove is carved in one side. Without this groove, the obelisk might slip across its base. But the groove acts as a brake, and it helps keep the obelisk aligned when it's pulled to vertical. The trick is getting one edge of a stone weighing hundreds of tons safely into the turning groove.
MARK WHITBY: So that it literally just moves from there onto the roller point here.
NARRATOR: Mark Whitby is one of Britain's leading engineers.
MARK WHITBY: And so we start applying the load -
NARRATOR: He's devised a unique theory of how the ancient Egyptians might have raised their obelisks. Inspired by the complex wood and rope-work on Egyptian ships, Mark has designed an elaborate system to rotate the obelisk slowly down onto its pedestal stone.
MARK WHITBY: Just pull it to vertical, and put it in the position much as it really is in real life.
NARRATOR: He hopes to try out his idea in a quarry in Aswan. A 30 ton granite obelisk has been placed atop an earthen ramp, and preparations are underway to lower it 12 feet into a turning groove. The first task is to assemble a large wooden framework that will provide the mechanical advantage to rotate the obelisk safely. In this supporting role is Rick Brown, a sculptor and timber framer from Massachusetts. At the moment, he has no idea that events will soon propel him to center stage in the obelisk drama. Meanwhile, Owain Roberts and his son Iolo are in charge of rigging nearly a mile's worth of rope. With all this rope and wood, Mark Whitby hopes to harness the giant stone, and carefully control its descent. While the engineer and his small army of assistants scramble to build their complicated contraption, Roger Hopkins is pursuing a completely different approach. With the large-scale obelisk already spoken for, Roger is left to experiment with a mini two ton block. And he's not happy about it.
ROGER HOPKINS: If they ever give me a decent obelisk to work with, then we can do something, but no, I always end up in Dogpatch with the puniest little - you know what I mean.
NARRATOR: Even though his obelisk is small, Roger still has to lower it with care. But instead of relying on ropes, he prefers a method that is more low-tech.
ROGER HOPKINS: This is more like an ancient elevator of sorts.
MARK LEHNER: So you're going to put it out onto this sand and then take the sand away to lower it down to its base.
ROGER HOPKINS: Yeah, we're going to drag it out, drop it on this pile of sand. Now I've got 21 tons of sand in here -
NARRATOR: Buried under 21 tons of sand is Roger's miniature pedestal stone, complete with turning groove.
ROGER HOPKINS: This block of wood goes all the way down to the turning groove of my pedestal stone. Likewise, so do the - I have a timber here and another one on the other side which will help guide me when I'm taking, removing the sand out from underneath the obelisk.
NARRATOR: Roger's homespun technique doesn't impress Mark Whitby.
MARK WHITBY: What we've got to do when you're moving these heavy stones around and wanting to put them somewhere is you've got to have absolute control over them. Imagine this for real with a 300 ton obelisk, and look at the sort of control Roger's got right now with his sledge.
ROGER HOPKINS: I want - you know, we've got to come - it's starting to shift over that way.
MARK WHITBY: There's a thing called planning. You have to plan every single step in advance, and it's not appropriate necessarily to run back and get the chainsaw and slice off bits of sledge because you haven't thought about how long it needed to be to begin with.
ROGER HOPKINS: That's it. Halas.
NARRATOR: In spite of Mark's criticisms, Roger is not alone in his support for the sandpit method.
MARK LEHNER: We have a number of pieces of evidence that sand was used in this way, for lowering colossal sarcophagi down tomb shafts, and for raising monuments like obelisks. There's actually an ancient papyrus where one scribe taunts another one, challenging him to design a way to erect a monument of thy lord, namely the pharaoh, could be an obelisk, maybe a statue.
NARRATOR: The 3,000 year old document reads, "Empty the space that has been filled with sand beneath the monument of thy lord... so that the monument may be established in its place." Many scholars believe the Egyptians used sand. But others argue that it's difficult to control. Removing it from around the base of a 300 or 400 ton obelisk could be dangerous.
ROGER HOPKINS: You know, we've come quite a way so far.
MARK LEHNER: OK, we got it pretty level for you all the way around.
ROGER HOPKINS: Yeah. A little bit here and a little bit there.
NARRATOR: After a couple of hours, the obelisk is reaching the bottom of the sandpit. And Roger is now removing the sand with his bare hands.
MARK LEHNER: Roger, do you think they would ever have been literally doing it by hand with a 400 tonner like you are?
ROGER HOPKINS: Yep.
MARK LEHNER: I'm asking - you think so?
ROGER HOPKINS: Yeah, why not?
MARK LEHNER: Now, you're in charge and you're doing this, so you can - watch out!
ROGER HOPKINS: Why? Watch out what?
MARK LEHNER: Well, it's moving.
ROGER HOPKINS: It just moved ever so slowly.
MARK LEHNER: Well, it looked freaky from here, with your hand under there.
ROGER HOPKINS: I could see it moving, I could even feel it moving.
MARK LEHNER: Now, do you think in ancient Egypt the guy in charge would literally be sticking his hand under there?
ROGER HOPKINS: If he failed, his head would be rolling.
MARK LEHNER: He'd stick his hand under there.
ROGER HOPKINS: He'd stick his hand under there. He'd want to make sure this thing was gonna go exactly the way he wanted.
MARK LEHNER: It's literally moving by millimeters.
NARRATOR: Millimeter by millimeter, the obelisk sinks lower.
ROGER HOPKINS: There's the turning groove, right there. And I've got my obelisk posed right over it. Look at that. Look at that, will ya? There it goes.
MARK LEHNER: Wow. That was its final adjustment. I'm glad my fingers weren't under there.
NARRATOR: Roger's obelisk came to rest at an angle of about 60 degrees. Weighing only two tons, it's not difficult to pull the stone to vertical. But the ancient obelisks were up to 500 tons, and pulling them upright was not so simple. To make the job easier, Mark Whitby thinks the Egyptians would have lowered their obelisks to a much steeper angle - like 80 degrees.
MARK WHITBY: Our goal with this method is to get the obelisk into as steep an angle as possible. Actually to get it to vertical with not a lot of effort. We're trying to control it very precisely in the way it comes forward.
NARRATOR: To make the obelisk go forward, gangs of men will pull on ropes suspended from the wooden frame. Mark hopes that as these ropes tighten, the obelisk will tilt downwards, and eventually rotate around the large pivot log.
MARK WHITBY: This mechanism is a bit of an ingenious device, but actually, I'm an engineer, and that's exactly what engineer means, an ingenious person. You know, as an engineer, it means we've actually planned the process. We've done lots of calculations. We've calculated dimensions. We've calculated weights. We're calculating how the weights move as the obelisk rotates. I'm happy our sums are right, but equally one has to double double check, and we're going to find out shortly.
MARK LEHNER: Mark has done a lot of calculations, and of course we know that the Egyptians had mathematics. They had fractions. They calculated slopes by rise and run. But they probably didn't use the calculations that Mark has used in order to design this system of raising an obelisk. The Egyptians would have approached it more by experience.
MARK WHITBY: And so the first thing to do is to actually apply some tension to the ropes pulling down here and to rotate it about -
MARK LEHNER: Mark's method has a number of things going for it. It assumes that the obelisk was tipped, which is very likely. And then it also uses outriggers of a sort, like they used in their nautical technology, their boats and their ships. It places great reliance on the use of ropes to pull the obelisk down in a very controlled way, and we know that they would have done this in a very controlled way.
NARRATOR: 60 men are brought in to pull on the ropes attached to the giant wooden frame. The time has come to test Mark Whitby's method, and see how well he can control the obelisk. Everyone is warned to stand back, just in case the 30 ton obelisk tilts too far, and topples off the platform. With each tug, the giant stone teeters precariously.
MARK WHITBY: Hold! Gently. Get the blocks in. The blocks in.
NARRATOR: Rick Brown places wooden chocks beneath the rising obelisk.
MARK WHITBY: I think maybe it'll be two to three pulls before - I believe, before it actually comes down onto this bearing. So I think we're doing quite well in that sense. It's not a bad system.
NARRATOR: Mark's first goal is to tilt the obelisk down so that the pivot log makes secure contact with the top of the platform. This log is then supposed to rotate right up to the edge - guiding the obelisk precisely toward its pedestal, 12 feet below. But the jerky rocking of the obelisk creates a problem that Mark did not anticipate: the giant log has slipped out of its intended position, and is moving dangerously close to the edge.
MARK WHITBY: We've come down on the bearing slightly in front of where we expected because the bearing slipped forward. As it rotates forward, it gets very, very close to that edge. Now, that's not necessarily a problem, as long as it doesn't come over the edge.
NARRATOR: The rigging team struggles to pound the log back into place. Fearing that the human pullers may jerk the obelisk off the ledge, Mark decides to supplement the pull with a counterweight - a three-and-a-half-ton block of stone. When its timber supports are removed, Mark hopes the weight of the stone will apply a steady downward pressure on the ropes, doing the work of 100 men. But as the stone is lowered to the ground, Mark finds that the ropes holding the counterweight have simply stretched. And the obelisk hasn't moved an inch.
MARK WHITBY: There's more stretch down here, Rick, than anything else.
NARRATOR: In spite of all his plans and calculations, Mark's method is not working. Desperate to make some progress, Mark decides to take a modern shortcut - suspending the counterweight in midair with a crane. But this risky move just causes more problems. Mark's quickly changing plans are taking their toll on the rigging crew.
MARK WHITBY: Are you with me, Iolo?
IOLO ROBERTS: I'm slipping out of your grasp a bit, mate.
MARK WHITBY: Well, what I'm saying is that - the knot. We've got to make a knot that works, or we've got to find another way of doing it.
IOLO ROBERTS: Well, the system I gave you before seemed to be working OK, now you've changed it to what you wanted now -
MARK WHITBY: No, no, no - what I'm saying is that that distance is now, is bigger.
NARRATOR: With morale plummeting, Mark Whitby must give up on the counterweight.
MARK LEHNER: Well, it's a very frustrating day, and most of the day was taken up with the counterweight, which in fact was just a substitute for a workforce that we didn't feel we could handle. The machines haven't worked, so now we're just going to try the people that we had intended to try in the first place.
NARRATOR: Over 200 men are put on the ropes. Everyone senses this is Mark's last chance to make his method work.
MARK WHITBY: Loosen those ropes!! Loosen those ropes, Rick!!! Loosen the ropes! Keep those ropes loose! Hold! Hold! Hold!
NARRATOR: Mark's old problem with the pivot log has returned to haunt him. Once again, the giant log has crept forward. And this time, it has gone too far.
MARK WHITBY: What's happened is actually - the log, as they pull, has walked forward. The design is on the basis that as it rotates it actually comes to an edge.
We're now so near the edge that as it rotates it may come off the edge.
And that's not nice.
NARRATOR: The pivot log has slid right up to the edge of the ramp, and now the chances of the obelisk crashing down have become too great. Defeated, Mark is forced to admit the situation is too dangerous, and decides to abandon the attempt.
MARK WHITBY: Well, right now I feel gutted personally and for the whole team. We've got to this point where we realize that to go forward would not be a good idea and is possibly negligent in the sense that we're putting at risk people's lives.
MARK LEHNER: I think we all made a critical mistake, not just Mark. We wondered what was the most complicated technology they had, and we said it was in boats. And then we said, "Well, how would they have applied that to a job like raising the obelisk?"
But in translating boat technology to the particular situation of the obelisk, we developed this - monster. And I think that was the wrong way to go about it.
MARK WHITBY: Hold! Hold!
NARRATOR: Another obelisk raising attempt has ended in failure. Most of the team is completely demoralized. Timber framer Rick Brown is the exception.
RICK BROWN: We know it can be done. It's just how far we want to go with the attempts. I think we can make it happen. I really think if we stayed here a week, we could raise this obelisk.
NARRATOR: But unfortunately, NOVA's time in Egypt has come to an end. Back at home, jobs and families beckon. The search for answers will have to continue somewhere else. 6,000 miles from Aswan, at a granite quarry in Massachusetts, a new plan is being hatched that may solve the obelisk puzzle, once and for all. Rick Brown is the one member of the team who couldn't give up.
RICK BROWN: I'm a sculptor, and I live in the world of making things. I have a passion for making things, and the idea of walking away was just - I just couldn't imagine not solving this problem.
NARRATOR: In Egypt, Rick was enthusiastic about Mark Whitby's plan, but now he decides to take another look at the sandpit. Rick liked the simplicity of Roger's method, but one thing worried him. Roger used sand that was slightly damp - it didn't flow well, and had to be dug out from directly under the obelisk - potentially very dangerous. Rick decides to use dry sand - abundant in Egypt's arid climate. With the help of his wife and fellow sculptor Laura, Rick begins planning a new kind of sandbox.
MARK LEHNER: Wow, look at it go.
ROGER HOPKINS: This is great sand you got.
RICK BROWN: This is dry sand. That's important. The sandpit is set up so that nobody ever has to go inside. It's perfectly safe.
MARK LEHNER: Is that the main advantage between this method and doing it the way Roger did it—where he was inside the box, digging?
RICK BROWN: Well, that way nobody is going to get hurt.
ROGER HOPKINS: Well, I didn't get hurt.
MARK LEHNER: So it all depends on the flow. You use the flow instead of diggers.
RICK BROWN: With dry sand, the sand will flow, with wet sand, we go home.
NARRATOR: The main force at work in the sandpit is gravity - the obelisk sinks under its own weight. But how is it steered into the turning groove? Rick will try to control the stone with several brake ropes. In addition, the back wall of the box is a series of steps - carefully aligned with the turning groove. After perfecting his method with scale models, Rick is about to get his turn with a 36 foot obelisk.
RICK BROWN: Well, Roger, we have a ramp, we have a 25 ton obelisk sitting on top.
MARK LEHNER: Maybe 30 tons.
RICK BROWN: Maybe 30 tons.
ROGER HOPKINS: I doubt it.
RICK BROWN: We have a sandbox. The sandbox is filled to the top with sand. And if you come up here, you can see this opening—that's our portal. The sand will flow right out of the portal. Right now it's choked off. What we're gonna do is we're gonna take that out by hand with hoes and pull all the sand out. As we do that, the obelisk will rotate around and fall right into the center of that turning groove.
NARRATOR: All the details of Rick's model have been scaled up for the 25 ton stone, including three gigantic ropes that run the length of the obelisk and are secured to two large brake logs. Assisting Rick are friends from the Timber Framers' Guild - a group dedicated to traditional building techniques. With everything in place, the team is ready to begin.
RICK BROWN: OK. Let's point this thing to the sky!
GRIGG MULLEN: All right, we're getting movement over here.
MARK LEHNER: We should get movement soon, they say.
NARRATOR: At first, the movement of the obelisk is almost imperceptible. But slowly, the point of the stone begins to rise.
MARK LEHNER: What we're doing here today feels very Egyptian to me. The ramp, the box, looks very archaic. The colossal ropes, the big logs, the sand. It's big and it's massive, but it's using very simple forces. Simply the force of flowing sand. They had no problems throwing thousands of people at the job. This is the approach the Egyptians would have taken.
NARRATOR: The approach takes time. After half a day of digging, the obelisk has only rotated a third of the way toward the turning groove. As the hours pass, and the obelisk sinks deeper into the pit, Rick's method is truly put to the test - when more and more pressure falls on the brake ropes.
MARK LEHNER: How much have the ropes stretched so far?
RICK BROWN: Well, the ropes have stretched around seven to eight inches.
MARK LEHNER: Wow, really?
RICK BROWN: Yeah, we're still well within the safety range.
NARRATOR: Rick's team predicted a certain amount of stretch in the ropes. But if their estimates are wrong, the obelisk could overshoot the turning groove. Tension mounts as the stone approaches the critical angle of 75 degrees. With the obelisk nearing the back of the sandpit, Rick can't resist the temptation to jump in and dig for himself. The obelisk is now leaning against the wall of the sandpit and is directly in line with the turning groove.
RICK BROWN: That's the turning groove, right here. You can see the curvature.
MARK LEHNER: Yeah, there it is.
RICK BROWN: And you can see, if I hold this tape as a straight edge, you can see where the obelisk is going to come right down inside the turning groove.
MARK LEHNER: Wow. That's a bull's eye. Direct hit.
RICK BROWN: We're just about nine and a half inches from the top of the pedestal stone.
MARK LEHNER: That looks pretty good.
NARRATOR: Now, it's a matter of gradually releasing the brake ropes - and removing the last bits of sand. For three more hours the work goes on. Finally, in the dark of night, and without a sound, the 25 ton obelisk nestles into its groove. When the sun returns, and the sandbox is removed, Rick can appreciate how far he's come.
RICK BROWN: You can see, we have the obelisk in the turning groove. It's at 75 degrees. Most of the hard work's done. But remaining is a task that is - could be daunting. And that is, we have to now pull the obelisk that last 15 degrees into the 90 degree position.
JOEL McCARTY: Those of you who have been trained in pulling, please come this way and report right here.
RICK BROWN: Well, the worst thing that could happen is that we lose control in the pull and the obelisk comes crashing down. This is a very tense moment.
GRIGG MULLEN: Go ahead and take the ropes and pull the slack out of them.
NARRATOR: Leading the pullers is Rick's colleague, engineer Grigg Mullen. Grigg's job is to scare the undisciplined volunteers into pulling slowly and gently.
JOEL McCARTY: You can't be talking.
GRIGG MULLEN: You all notice - I'm married. You notice what's missing on my hands? Go ahead and take your rings off. If one of the ropes flies, it can catch your ring, and it will pull the meat off your finger. All right, go ahead and take up the slack. Take it slow, get it light. Keep pulling.
NARRATOR: If they pull too hard, the fragile obelisk could topple over and crash to the ground. To prevent this kind of disaster, Rick's team is once again using brake ropes. While the gang below pulls the obelisk toward vertical, the brake crew holds it back, letting the ropes out slowly, so the obelisk can't work up any momentum.
GRIGG MULLEN: The brake lines have got it. A little more, a little more.
RICK BROWN: We are at 89.
GRIGG MULLEN: What have we got?
RICK BROWN: 89 degrees. We have touch down! Woooo! We have a free-standing obelisk!
MARK LEHNER: Your inspiration, Roger.
RICK BROWN: This is the way the Egyptians did it. This is the way we did it. We were mimicking the Egyptians. It's a very perfect moment.
MARK LEHNER: The Egyptians had to do it with as much control and just as slowly. Because they not only had months and months of hieroglyphs that had been cut, people may have died, a lot was invested. And they would have had just as much control. I'm glad we got it done.
ROGER HOPKINS: Common sense. What I knew intuitively would work, proved itself. I'm a happy camper.
RICK BROWN: This is the kind of thing that we had hoped for, and it happened because from the very beginning we believed that if we acted and thought like the Egyptians, that we would have success. You know, the Egyptians were learning through keen observation, looking carefully at all the details. They learned how these materials behaved and once they understood that, they used those forces of nature to be able to do something as magnificent as this.
NARRATOR: When the great obelisks of Egypt were pointed to the sky, the engineers in charge of the raising would have done all they could to protect the pharaoh's monument. Most likely, the process was slow and painstaking, relying on human sweat and the gentle force of sand. The method may have been simple, but the result was spectacular.
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