Posted on 12/01/2006 3:55:23 PM PST by Rodney King
The Ancient Egyptians built their great Pyramids by pouring concrete into blocks high on the site rather than hauling up giant stones, according to a new Franco-American study.
The research, by materials scientists from national institutions, adds fuel to a theory that the pharaohs’ craftsmen had enough skill and materials at hand to cast the two-tonne limestone blocks that dress the Cheops and other Pyramids.
Despite mounting support from scientists, Egyptologists have rejected the concrete claim, first made in the late 1970s by Joseph Davidovits, a French chemist.
The stones, say the historians and archeologists, were all carved from nearby quarries, heaved up huge ramps and set in place by armies of workers. Some dissenters say that levers or pulleys were used, even though the wheel had not been invented at that time.
Until recently it was hard for geologists to distinguish between natural limestone and the kind that would have been made by reconstituting liquefied lime.
But according to Professor Gilles Hug, of the French National Aerospace Research Agency (Onera), and Professor Michel Barsoum, of Drexel University in Philadelphia, the covering of the great Pyramids at Giza consists of two types of stone: one from the quarries and one man-made.
“There’s no way around it. The chemistry is well and truly different,” Professor Hug told Science et Vie magazine. Their study is being published this month in the Journal of the American Ceramic Society.
The pair used X-rays, a plasma torch and electron microscopes to compare small fragments from pyramids with stone from the Toura and Maadi quarries.
They found “traces of a rapid chemical reaction which did not allow natural crystalisation . . . The reaction would be inexplicable if the stones were quarried, but perfectly comprehensible if one accepts that they were cast like concrete.”
The pair believe that the concrete method was used only for the stones on the higher levels of the Pyramids. There are some 2.5 million stone blocks on the Cheops Pyramid. The 10-tonne granite blocks at their heart were also natural, they say. The professors agree with the “Davidovits theory” that soft limestone was quarried on the damp south side of the Giza Plateau. This was then dissolved in large, Nile-fed pools until it became a watery slurry.
Lime from fireplace ash and salt were mixed in with it. The water evaporated, leaving a moist, clay-like mixture. This wet “concrete” would have been carried to the site and packed into wooden moulds where it would set hard in a few days. Mr Davidovits and his team at the Geopolymer Institute at Saint-Quentin tested the method recently, producing a large block of concrete limestone in ten days.
New support for their case came from Guy Demortier, a materials scientist at Namur University in Belgium. Originally a sceptic, he told the French magazine that a decade of study had made him a convert: “The three majestic Pyramids of Cheops, Khephren and Mykerinos are well and truly made from concrete stones.”
The concrete theorists also point out differences in density of the pyramid stones, which have a higher mass near the bottom and bubbles near the top, like old-style cement blocks.
Opponents of the theory dispute the scientific evidence. They also say that the diverse shapes of the stones show that moulds were not used. They add that a huge amount of limestone chalk and burnt wood would have been needed to make the concrete, while the Egyptians had the manpower to hoist all the natural stone they wanted.
The concrete theorists say that they will be unable to prove their theory conclusively until the Egyptian authorities give them access to substantial samples
There were extensive forests upstream on the Nile, easy to fell and float downstream; not to mention those cedars in nearby Lebanon.
Analogously, there's a gold mine in Brazil that is now a big pit mine, but started as a small mountain. The transformation was accomplished one 40 pound bag of earth at a time, up and down ordinary ladders.
You could carry it up in 30 lb baskets. It would be rather quick to construct.
I think they are right.
Why mold it into blocks at all, then? Why not just do flat layers?
To burn enough lime for a large pyramid, one would need A LOT of wood. An 8 megaton pyramid - say, 2000000 ton of lime. 20 years time frame. 100000 tons of lime a year, 300 tons of lime a day, something like 1000 tons of wood per day. Egyptian expeditions to upper Nile were never large enough to pull out this kind of logging. And Egyptians in Lebanon date to much later times.
Zahi "Zowie" Hawass also has claimed that the number of stones in the Great Pyramid (Khufu, a.k.a. Cheops) is more like 500,000, compared with 2.5 million which is commonly believed, or more than (I think it was) 4 million calculated by someone writing in KMT a few years ago. Hawass also claimed that the size of the stones is something like 1000 pounds each, instead of 2+ tons as is commonly thought.
The logistical problems of dragging 2 1/2 ton stones up sand ramps (one wrapped around the whole structure, or whatever), plus the stones which are much larger, plus the now-missing facing stones (stripped by some caliph during the Middle Ages) in the 20 year time frame attributed to its construction creates these kinds of problems.
Ewwww. LOL!
Because it would require getting the lime uptop too quickly.
That is my guess.
P.S. During the Ice Age.
Well, in Egypt's case, the land in the immediate Nile Valley isn't that cruddy, and the annual flood would replenish it. In Roman times, Egypt was considered a breadbasket and its exported grain fed much of the empire. Combine that with the security that the surrounding deserts provided from aggressive neighbors and Egypt becomes a pretty attractive place.
see # 66. Where are the ruins of gigantic industrial lime kilns? The lime works would themselves be the size of a pyramid. And if it was done in mom-and pop ovens, then multiply the fuel amount by 2 or 3.
I read a fun book about along those lines. The ancient Egyptians may have built simple cranes for the purposes of transporting limestone blocks. The book title, which is the first difficult bit to swallow, is:
"HOW TO BUILD A FLYING SAUCER: AND OTHER PROPOSALS IN SPECULATIVE ENGINEERING"
by T. B. Pawlicki
includes sketches for cranes that could have transported the pyramid stones to Giza as well as some investigation as to what might have survived thousands of years later, such as large rounded stones with holes in them that are currently used as grinding/millstones.
Lime kilns are a later technology. The article says that they may have dissolved soft limestone in ponds of water and then taken the resulting slurry uptop to pour it in the molds.
This really looks possible. The Egyptians were quite good stone workers. Their word for potter was actually "stone worker".
And probably made about the same time.
Richard Hoagland on the other hand.....
cheeze=cheese. Adjacent keys typo, more caffeine needed.
Just a guess, but probably "All you need is love"
*Sophocles
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