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I've heard that there are stone walls on Easter Island that look very much like the Inca stone walls. Have you seen them, and do you know if there is any evidence on Easter Island about how they might have been built?

In your recent program you had two options for the Inca's ability to create their magnificent stone walls. I believe that the Incas might have had a different approach. Instead of working vertically between two stones with the second being supported precariously above the first, they could have worked horizontally by placing the stones on their sides and working on two or three joints with three or four stones at one. They could have used the compass to transcribe one stone's features to the next. Then when both joints are finished, they would set the first stone of the wall. With the joint between the second and third stone already complete, they would start on shaping the fourth stone to a side of third stone, and so on until completion. This method would have the advantages of only moving the stones which could be enormous, once, without the danger of perching a several ton stone above a skilled stonemason.

One person tried using mirrors to heat the rock to chip away pieces of the rock without any success. I think his idea would probably have worked if he would have used something like a crystal, which should be native to the region, to pinpoint the heat of the mirrors on to the rock.

When they built the grass bridge, how did they send the rope from one side of the gorge to the other?

Could it be that the Incas used friction between massive blocks and actually ground them together to get the perfect fit, possibly laid one block on its side on the ground and somehow rotated the other one on its side on top of it until it was a perfectly flat surface, then take the next block that will mate up with it and grind it down in the same way? I have seen them and it is incredible how they did it.

Vince, how did you first become interested in Inca civilization?

How many suspension bridges are there in the present day Inca empire?

I think the stonemasons used mud casts to generate a perfect fit between the large stones. First they smoothed the stones as much as possible by hand. They then made a mud cast of one stone face. They had to let it dry. Then they used it to grind the other stone into shape until it made a good fit.

What did the Incas have to secure the stonework into the mountains?

How long will the grass bridge that was built last?

Vince, how did you first become interested in Inca civilization?

I have noticed that between work they ate guinea pigs and potatoes. What other staple foods did they have?

I'm interested in the record-keeping in woven strands. Was there any archeological evidence to support this method?

The show didn't mention the political system the Incas used to rule that large an area. I have done some reading on this and find it fascinating. Have you done research on the Inca political system?

How does the shaping of the massive blocks compare with other ancient structures like those of the Egyptians', the Greeks', Romans', et cetera, tools used?

What type of rocks were the Incas using? Is there a difference between the wall rock and the rock used for forming the angles?

Had the Inca walls been x-rayed or examined otherwise behind the exposed face? Perhaps it's only the front face of the stones which fit together so well. Though still challenging, it would reduce the apparent difficulty a bit, a pretense hiding reality. That would make the Incas the first advertising agency.

Did you give any thought to the way the Incas originally carried the stone before bringing it to the building site? If they were able to break up a very large stone into building block size and keep a record of the original sequence of breakage and then reconstitute that order at the building site they could save a great deal of work in reshaping, since the blocks they were putting together had originally fit together in the first place, and a minimum of polishing would be required.

At the height of the Inca empire, what was the population?

Didn't they drill holes in the rocks, pour in water, let winter come to freeze the water, which expands the water, thus cracking the rock?

Do the blocks need to fit perfectly throughout or just along the edge? Is there any evidence that they were less careful nearer to the center of the blocks?

It appears that the modern civilized world is no match against the Inca's ability to motivate a large labor force. The effectiveness is awesome. What do you think enabled this incredible phenomenon?

Why was no information about the methods used for the construction of the walls passed on to the descendants of the builders?

What types of weapon artifacts have you uncovered? Atlatal, bow and arrow, bola? Also what tools are evident?

What was the dress of the ancient Incans made of and was it colorful? It is pretty cold up there in the mountains, isn't it?

Just as the bridge was built with a group of people living near the river, is it probable that the Incas could have gathered large groups of people to work on the stones? Is it possible to have had large groups of people working on the stones at one time in order to build the temple and other buildings?

Were the workers slaves for life or were they allowed to return to their native lands?

Did the Incas trade outside Peru by land or sea?

What is the latest information on what class of Inca resided in Machu Picchu?

Are the Incas the earliest recorded inhabitants of that area in Peru?

Is it possible the Incas could have moved the stone blocks by rolling them over lengths of cordage placed across the route?

How do you think they found a true level and vertical?

Did the native Andean people eat any distinct food which helped them to better cope with the high altitude air that they work in?

I once read that the joints in the Inca masonry walls were made by spreading fine sand between the blocks and then sliding the blocks against one another so that the sand, acting as an abrasive, wore down both blocks evenly. It was also said that there were protrusions on the blocks where ropes could be attached to facilitate the grinding motion. These protrusions were then knocked off after the stone was in place. Have you heard of this technique? What are your thoughts on its veracity? Thanks for your attention.

In an earlier response you talked about the foods that the people ate, but you didn't mention any protein. What was their protein source?

One way to fit large stones together would be to create a wooden form that would be lightweight and would fit up against one face of one stone or a section of it. The stone would be smoothed to fit the form. Then another wooden form would be created to fit into that wooden form. The second form, which now fits perfectly into the first form, would be placed against the second stone. The second stone could be polished until it fit the second wooden form. At that point the first stone would now fit into the second stone and would only have to be moved once.

Is there any evidence that the master stone cutters were highly respected in their society? In other words, were they at the top of their social ladder?

Do you know the length and height of the largest span where the ramparts or tie-downs for suspension bridges have been found carved into the rock as you found in the village at the show? Also would making the side walls higher reduce the likelihood of flipping a bridge like this? The bed of the bridge needs to be relatively taut to provide a path a human can walk across but the looseness of the side rope should have some impact on its stability. Is there any evidence that the base of the bridge and the side walls might be anchored at different levels on any of these bridges?

Gold leaf is a very pliable metal. Is it possible that the Incas lightly hammered a thin gold plate onto the receiving stone surface, then lifted it and used it as the pattern for shaping the base of the stone that would rest on it?

Could the elements of the stones have been sanded down or broken down to powder form, then reformed with water into a square mold left to harden.

I am surprised at the lack of inquiry in the idea that the water surrounding the Inca empire wasn't used. They had the means and skill to cause those rounded joints, to hammer away by suspending water and rope. The erosion of the rock is already evident, but seems to have been looked over, the rounded rocks used for cutting are obviously eroded by the river, the mountain terrain would've provided the perfect opportunity to build such a system, divert the water and set up a station at which to erode the pre-determined stone. Am I in blatant misunderstanding or is this a realistic theory? Thanks for any response.

Are their still places that have not been found left by the Inca. Is their proof that the Inca may have sailed across the oceans and or other people sailed across exchanging information, culture and ideas? If so where can this information be found?

Vince, I recently (April,1998) had the pleasure of visiting Cuzco to implement a curriculum written by me on the subject of Implementation of Internet for the KHIPU Institute. While there I was given tours of Machu Picchu, Sacsahuaman, Urubamba, Chinchero, and others which I choose not to spell, but I'm sure you know of which I speak.

My question is on the "cracking/cutting" of the stones theory. It is my understanding that holes were placed in the rocks. Then branches were placed inside and watered to make them grow, thus cracking the stones. What is your take on this and did you test this method?

The straw bridge built in the Inca tradition, how long could it last? Does it rot with the natural conditions of rain? Or does it crack and crumble under the sun's UV rays?

I visited Machu Picchu in 1984. At that time, the guide told us that probably the Incas used special herbs to "melt" the stone and give it the correct shape for their constructions. Have you heard about this before? Unfortunately, he explained, no record of which herbs were used to perform this was kept.

I thought Vince Lee was very correct, also with the tool he used for carving the edges. Could this perhaps have been done, only with the large stones being carved out while laying on their sides-as sort of a jigsaw puzzle, and then erected AFTER all the sides had been carved and smoothed so perfectly. Moving them with more of the ease as was shown in the moving of the large stone by the townspeople AND the use of the tool?

What evidence, if any, suggests that the Inca civilization had the same environment as we see today? Is it possible that melting glaciers or other natural weather forces played a part in the material handling aspects of building some of the Inca structures, and/or aided the Incas with water and food supplies?

Was it fun being there and building the bridge? I enjoyed the show.

How elaborate were the Incas involved in directing water to their settlements for plumbing and other purposes? Did they rely on going directly to the water sources like streams, lakes and rivers? Or did they have a somewhat elaborate public works system?

Would it have been possible for the Incas to have a slide made of logs to pull them across the valley to where they would be used?

With respect to that mirror theory, you mention that you have seen no evidence of melting of rocks anywhere. I saw a program on a show called "Timeless Places" and it showed interesting pictures of some rocks at a quarry in Q'enqo that look remarkably like they were melted. There are sections of rock that look like someone was testing some tool (they looked similar to scribbling with a ball-point pen when the ink dries up). The pictures were quite startling. Are you familiar with these features? and do you have any explanation?

Other conjecture mentioned was about a place (I forget where) that may have had a room that was lined in gold which may have formed some kind of capacitor. This is a little bizarre, but quite intriguing. They conjectured that they could see possible evidence of some kind of control box. Some power source may be possible, but thanks to the conquistadors, we may never know.

Also shown at Q'enqo were blocks of stone that were in mid-excavation, and there were these large (18" dia) bore holes around the block. Could these bore holes be made using the hammer stones?

Is it possible that the Inca builders planned the placement of each stone so well in advance that they were able to fit the stones while they were still in the quarry? Then each could be moved to the site and placed together like a jigsaw puzzle piece.

Could the largest stones have been fitted by scribing the seat to a casted copy (supported by timber lattice) of the faces of the stone? It would weigh MUCH less, and could be designed with lashed "legs" for safe positioning & working under. With accurate reference marks, it might even be done in sections.

Could the Incas have made mud castings of the surfaces of the stones as templates for the fitting? I believe that the method you used was too tedious and unreliable for such incredible results.

The Incas were serious mathematicians, they knew numbers, they used the Quipu, which is an elaborated little machine made with ropes, and knots, different lengths and sizes, well my theory is that they calculated every single man, and size and position of every single stone can you explain on this?

I was wondering if all Inca walls and or monuments are just 1 layer thick? you talk like they are. this may be a flaw in their flawless seemingly process. the Egyptians had many layer thick pyramids, yet the Inca didn't? maybe this is a flaw in their design because it was only designed to fit the first 3-4 sides of the rock, and not lass 6 sides...

Is it possible that the Inca people lifted up the stone blocks onto the rest of the wall by a system of ropes and pulleys, or would they not have that technology yet?

In discussing the question of how the stones were set together so well, especially the very large ones, Jim came up with a thought. The large stones cannot be moved easily to continually test the set. Perhaps a substitute was used. If a grass & mud mold were to be made of the large stone, one could cast a lighter version of the stone (perhaps also in grass & mud) with which one could use to fit the stone setting. One need not cast the whole stone but only the corner being set. At first I thought any detail would be lost in the casting, but then I thought about how bronze figures are cast. Is there a possibility that castings could have been made of some local material that would have allowed the detail of the stone to be preserved?

Isn't there a group of Inca descendants that might know about the Inca architecture—about the Incas not having the wheel, metal tools and so on? How much of a fact is that?

How much land did the Inca kingdom covering square Kim's? How many tons would the largest building blocks be?

Has anyone been able to replicate the Incas' ability to position stones together with seams so tight that a razor blade cannot penetrate the seem? Do we know how they managed to do this with their "primitive" technology?

I have seen on TV that hot air balloons could have been made from local materials in the vicinity of the Inca empire's boundaries. Could a team (10 - 15) of these balloons plus ground-based manpower have lifted the stones across the river and up to the sun temple? If the balloons let the stones hover in midair, that would also enable precision carving.

THEORY ONE: I understand that the Incas did not have the wheel and modern block and tackle but even ancient cultures used something like a "gin pole" to provide leverage and act as a hoist to lift things.

THEORY TWO: It occurs to me that an overhead grasp of these large rocks would provide the underside access that the method shown on the program did not. It would also provide the control to list, hoist and adjust that the manual method did not.

THEORY THREE: The notches on the lower edge of the rocks I can visualize as grapple points but I think a tool like an "ice tong" that has a center fulcrum and curved or pointing up tips might have provided the grasp that the sticks from below did not. Would a forked branch with a long leg and a short tip used in pairs be the kind of tong to grasp a rock from above? The weight of the object tightens the grip until you lower the gin pole or hoist and remove the pressure.

THEORY FOUR: The Incas obviously had rope technology. I think I have even seen examples where raising and lowering an object was probably used so they must have had crude open hole block technology. If you look at the Phoenician, Egyptian, Greek, Malaysian boats and the RA and the Kon Tiki they all had some block technology to change pressure on a line. Even a three hole block provides a tremendous amount of lift. Four or five hundred years ago there were sailing boats with this kind of technology. Certainly a culture this advanced would have been able to grasp the concept.

THEORY FIVE: I am not quite ready to accept the parabolic mirror theory as a construction tool but they may certainly have provided some communication between way stations.

THEORY SIX: As we know, the wet rock provide a very able path to move the stone. The Inca had many waterways. The cobbles provided a bearing surface with significantly less friction than the bare dirt. We know that there appeared to be a roadbed under the stone that was moved. On top of the roadbed there was grassy material. Have you ever walked on wet grass on a surface that had little friction? You may remember what the sky looked like while you were lying on your back. What is to say that they did not lubricate the grass on the cobbles with water, mud, or manure to move the gigantic stones?

THEORY SEVEN: Incidentally sliding these large rocks on a cobbled surface would be like rubbing wood on sandpaper. It would leave a smooth, abraded surface.

On the show I saw tonight regarding the magnificent building that were made of stone fitted together. When pulling the heavy stones up the steep grade and then down the steeper grade, why couldn't they have used the weight of the stone going down to help pull up the stone on the other side of the top? It might also help control the speed of the stone going down. If they could get a small stone to the top, they could use it as a counterweight for the next stone which could be heavier. If they used progressively heavier stones, it wouldn't take a much man effort to push the stone up and it would really help the stone going down as it would be counterweighted by a heavier stone going up.

I noticed in the program that the easiest way to transfer a rock was through the stream bed. Stone on "wet" stone. Have you considered that the Incas may have wetted the stone and slid the rock over the trail. Or even yet, transferred the stone over wet straw on wet stone roads. You may find that the coefficient of friction is much less than dry stone on dry stone.

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