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List of Questions

Questions & Answers | List of Questions

In the NOVA about Stonehenge, the A frame you made had the ropes that the volunteers pull higher than the ropes connected to the rock, and in the NOVA about the obelisk, you had the ropes at the same level. Wouldn't it be easier if you had the A frame like in the NOVA about Stonehenge?

Will it be possible to hear a discussion of the obelisk containing the code of Hammurabi? Is the obelisk containing the code of Hammurabi still in existence?

Would the Egyptians have used elephant power to raise the obelisk? They were excellent builders and had a great understanding of mechanics. It seems to me that elephants would be cheaper and less troublesome than slaves, as well as pound per pound much more powerful than men.

What was the general attitude of the 200 men who were working on site, the common man's attitude to this project, if you will?

What was the time period you had to raise the obelisk?

Why not use a pulley on level ground to gain a mechanical advantage for the pullers?

Why not anchor the base in the groove stone with a team pulling in the opposite direction to the lift?

Do you think having more people pulling to try to erect the obelisk would have made a difference?

Have you considered a rising road bed level on the lever side of the obelisk, also decreasing the height of the A-frame and extending ropes, as the Pharaohs had many more than 200 willing participants?

How many finished obelisks are there in existence now? Were they cut from the same type of stone? Is there any indication about who the sculptors were?

You need to raise the obelisk on a ramp to a height where the center of gravity is at its final height, then secure a frame at the center of gravity, which can be used to pivot the obelisk, which is now balanced at its center of gravity to a vertical position.

How different was the scale of the pyramid building from the scale of the obelisk quarrying and raising?

Don't you think that they would have come up alongside of the river in order to allow the pullers have the room to move it and then do the hole under the stones supporting it by three stones or so? You could then build a boat or many boats under the stone and let it float out into the river and reverse operation into the end.

Is there any symbolism involved with the shape of the obelisk?

Instead of using pullers to have to work over their heads, why don't you use a technique called a Spanish wind blast? The rope is anchored at some strong fixed object. By then twisting a looped rope, a tremendous pulling force can be applied over the A-frame by a few people.

How did you calculate the number of men needed to man the ropes?

Why were there no women involved?

Why not use a variation on hydraulics? If the ropes were fastened down, isn't it possible to wet them, tighten them, let them dry and shorten, place solid rock under the slightly lifted obelisk and repeat? After all, it's the desert.

The process so far seems correct, however, I might suggest the use of timber braces anchored to the ground and lift the obelisk from the backside as we do in the "barn raising" method.

Did you try the counterweight idea that was suggested by the owner of the quarry?

Why didn't workers stand on the levers when they became too high to reach in order to utilize their weight to increase the downward force on the lever?

What other obstacles did you and your colleagues face, not including the problems of transporting and testing?

Wouldn't a series of A-frames beginning at the top of the obelisk and being succeeded by a taller A-frame, as the first for the job and so forth, cement the levers that could be filling in the space behind the obelisk with rock and dirt to the point at which the center of gravity is over the base and the obelisk was standing by itself? Would this work?

Would it be possible to create a supporting cage-like structure at the bottom of the obelisk made from wood? This would have to be strong enough to withstand an impact into the bottom of the pit. Once in, with the extra angle while the men were pulling, it could be set on fire, a wood version of the sand pit. The only problems I see are the speed of the barn and how much heat the obelisk could withstand. Good luck.

It might be easier to slide the obelisk down a concrete ramp to the anchor stone rather than drop it, using sand and creating guess work. That way, a short, lightweight wooden test obelisk could be used to work out the proper alignment between the obelisk and anchor stone. It might also be easier to create a raised hill behind the obelisk so that the A-frame would rest above the obelisk. The pullers would be on the down slope of this hill. What do you think?

Could not triangular wedges in alternation—small to large, with the small making room for the large—be used from the rear to lift the obelisk?

Weren't slaves used in Egyptian times to move the obelisks?

When are you going back to Egypt to try this again?

Were the pyramids built at around the same time as the obelisk?

Did your experience trying to raise the obelisk, but failing, give you any ideas about how to do it better?

Have any obelisks ever fallen over?



How was the bottom side of the obelisk (attached to the quarry) freed from the granite?

A smaller version of the obelisk had been raised by draining sand from underneath it. If there were stops in the movement of the obelisk, such as poles placed in layers through the sand, wouldn't that solve some of the problems in positioning the obelisk at the right point to meet the turning groove?

Somebody recently proposed that the ancient Egyptians might have harnessed wind power to raise obelisks, using giant airfoils or kites. What do you think of that notion?

The same small canal that was built to float the stone to the site could be used to fill a large pool that is built higher as the water level rises. Animal skin bladders attached to the obelisk would gently float the stone upright. This method would "baptize" the stone in the holy water of the Nile as well as provide an aqueduct and reservoir for the workers and city. It's just a theory but it seems plausible.

How did 400 tons of granite get on to the sled?

I'm just curious why an engineer was not included on the erection team. In 30 minutes I calculated all the forces and geometries necessary to raise the obelisk using sophomore level engineering skills. I estimate that with two wood structures (similar to the one used in the team's last ditch attempt) and a platform capable of supporting 1/4 the obelisks weight the obelisk could be lifted with between 150 and 300 men (assuming each could generate a pull equal to his weight). The Egyptians are famous for their fantastic engineering feats. Isn't it foolish to try to duplicate them without extensive knowledge and understanding of the field?

Are there any ancient records at all, however obscure or fragmentary, on how obelisks were raised?

Is there any danger that when you manage to tip the obelisk into its upright position that it will topple over the other side from its momentum?

Did all the effort that went into building these massive monuments, like the pyramids and the obelisks, use up so many resources that it was detrimental to society?

It seems like working on a project like raising the obelisk or building a pyramid would be, while hard, very rewarding. Can you think of any projects today that would generate a similar feeling?

What is the significance of the writing on the sides of the obelisk?

When you go back, how many methods will you try? And will you have the same amount of time and other constraints as you did last time?

Did working on this experiment make you feel at all like you were able to get inside the minds of the ancient Egyptians?

What do you think accounts for people's fascination for all things Egyptian, especially the pyramids?

Do you know if there are any obelisks in private collections?

When did the society that was responsible for building the obelisk come to an end and what caused its downfall?

Do you think the Egyptians knew that the granite was extremely durable and chose it for that reason or was it just the material they had available to them?



Why was the obelisk seated into the turning groove at a 32-degree slope? Was it because the breaking system was not adequate? Solve this problem so that you can begin the raising from a 45-degree or greater start point. Now, how about some camels, oxen, horses, or elephants for some real power? Good Luck, and Aloha from Maui!!!

It seems to me if you can not pull the thing up why do you not just push it up? I would tend to think that if you applied force to the other side of the obelisk it could possibly go up easier than if you pulled on it from the side you are. By the way I loved the sand trap ideas.

The ancient Egyptians were the most prolific stone movers in history. Is there any written history on how they may have moved massive stones over large distances? I remember seeing a show on TV where the stones were set in place by dragging them over a hole filled with sand, the sand was then removed through an access tunnel, and the stone was slowly set in place. The effort required (by any method) to move the Stonehenge stones over a 20-mile distance would have negated any method of raising them that would have been considered a gamble. Although your system worked, I believe the stones were set into place with some type of dampening agent to ensure that the stones were not damaged. What do you think?

What is the estimated time (months, years) that it took the ancient Egyptians to erect an obelisk (e.g., the largest one), from the first chip in the quarry to the final touches of the upright piece?

Rather than using a ramp composed of two straight sections, why not use a parabolic curve in the second part of the ramp? The parabolic part might help move the obelisk around since the contact surface is reduced (though you'd need a much stronger sled) and as the drop rate could be controlled, it gives a better chance for the obelisk not to break upon landing on the base. Furthermore, that might help position the obelisk closer to vertical—then it would be easier to pull to its completely vertical position. What do you think?

How did the Egyptians make the giant mounts of dirt?

My husband and I sail a 42-foot sloop. On our mainsail, we have a multiple-block system that allows me (at 130 lbs.) to adjust our mainsail with one hand. The Egyptians were accomplished boaters. Is there any evidence to suggest that the Egyptians may have had similar technology? If so, could you use it with your A-frame structure to lift the obelisk?

Weren't a lot of obelisks put up two at a time? If so, then couldn't a lowering platform for one obelisk be used as a raised level workman platform for the second obelisk? Efficient use of mud-brick with no need for A-frames.

I have a book called "Babylon Mystery Religion—Ancient and Modern" by Ralph Woodrow that includes a chapter on obelisks. On chapter five, page 34, the obelisk at St. Peter's Square at the Vatican is depicted in an old drawing being raised inside an elaborate giant scaffold-like structure surrounding the obelisk lifting with ropes from the top. I can't tell, but pulleys, which certainly increase the mechanical advantage, may be at the top of the structure. Would this technology have been available to the Ancient Egyptians?

Could the structures shown near the obelisk have been used to erect them? A drum connected to the nearby structure could be used to wind up a rope, thereby lifting the obelisk into position. This would require the technology of turning the drug (or roller) as the method of propulsion (like a come-along) instead of pulling the object with ropes and using the rollers only as a way to reduce friction. Did they have this technology?

Do you believe the ancient Egyptians saw the obelisks as holy? Also, as I watched your show someone said that the ancient cities were built to last through eternity. What was the logic behind that question? Did the Egyptians actually believe their empire would last forever?

Make an A-frame, put the crossbar 3/4 of the way down. Then attach ropes to the obelisk (at the top) and to the A frame (at the top). Now attach more ropes to the crossbar, have your volunteer crew pull these. This will increase your leverage and multiply your pulling power 3 times. This should be more than enough to right the obelisk.

Could the wooden support that the obelisk rests on, as it is dragged to its resting point, have wheels at its base (somewhat like a dolly), so when it is in the tilting slot or groove, it would be easier to put upright (like our arm and elbow), then when it's in position, burn the support dolly at the same time making settling adjustments.

I think if they used a column or wheel of significant weight to roll down a ramp a precise distance and speed with said wheel or column winding up pulling ropes as it travels. I think diameter of wheel plus weight of wheel plus angle of said ramp, plus using A-frame would lift obelisk.

I would like to throw in my two cents about how to float the obelisk. Did you forget that the Nile is only recently the victim of human flood control? Ancient solution: build a drydock on the flood plain. Tie a barge off atop the drydock. Load the obelisk during the dry season. Wait for the floods—float away. Tie up at a similar facility down river. Wait for waters to recede. Unload the obelisk. Stone/rock piers aside the drydock would help in on/off loading.

On the show, the obelisk is left unraised. Was the obelisk ever raised? The show is several years old; have there been any new discoveries that show how the ancients raised a 400-ton obelisk?


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