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Pyramid Stones Were Poured, Not Quarried
brian0918 writes "Times Online is reporting that French and American researchers have discovered that the stones on the higher levels of the great pyramids of Egypt were built with concrete. From the article: 'Until recently it was hard for geologists to distinguish between natural limestone and the kind that would have been made by reconstituting liquefied lime.' They found 'traces of a rapid chemical reaction which did not allow natural crystallization. The reaction would be inexplicable if the stones were quarried, but perfectly comprehensible if one accepts that they were cast like concrete.'"
My dad always used to tell me that when Alexandria was burned, all the publications holding the Roman recipe for concrete went with it. That, he claimed, was why all concrete poured was inferior to the Roman Aqueducts. And why it wasn't until 1948 that the right combination of limestone & other minerals was discovered to be able to resist water and hold that high a level of precision. Cement/concrete are by nature porous surfaces and so often sap water which causes structural problems. The fact that the some of the aqueducts still hold their accuracy within inches of their architectural specifications after 2000 years is nothing to overlook.
If Egyptians (for thousands of years prior to the Romans) had experimented with or refined this process and if an Aristotelean (such as Demetrius of Phaleron) had moved this information to Alexandria, that would explain how the structures like the aqueducts were constructed with such high quality mixtures.
I have one tiny problem with the summary as the article states: While summary uses the word cast: I would like to point out that this is known as forming concrete and not casting concrete. The difference is like the difference between pouring concrete for a foundation of a house and laying brick. Laying brick is casting while pouring concrete (like the article alludes to) is called 'forming.'
This might sound like a small matter but laying brick & forming concrete walls are two entirely different professions.
In all honesty, if you were to ask me to construct a pyramid today--knowing what I know, I would build the core of the pyramid out of laid brick. And then I would, starting from the bottom, form up the angled sides and fill in those areas. If you're wondering why I would take this route, try it with paper. Cut out blocks of paper from a notebook without making marks and try to make a perfect angled edge between them. Pretty difficult. Now try it in three dimensions with 2000 year old tools.
It makes sense that they would have both technologies (like the article states), one quarried for huge bricks and the other formed up ash, salt & lime. It would also explain a lot of technologies the Romans had.
My work here is dung.
because in science, a hypothesis is interesting, but prooving a hypothesis is important. What you heard was the hypothesis. This right now is the information that major strides have been made towards actually prooving it.
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Go look at a concrete highway sometime, and check whether the concrete is continuous (like asphalt*) or whether it has regular seams. There's a reason for the seams: namely, that concrete expands and contracts with temperature. If we poured roads as once continuous chunk they'd expand in the heat and buckle, or contract in the cold and crack. The seams are there to relieve the temperature-induced strain.
Now, consider the fact that the Egyptions lived in the middle of the desert. One particular feature of such a climate is that there are wide extremes of temperature: it gets really hot during the day, and really cold at night. Once you realize that the Egyptions probably had prior experience with the materials before trying to build the biggest structure in the world out of them, you might expect that they'd realize the same thing current civil engineers do, and put in releases to prevent cracking. In 3D, this would mean pouring the concrete in blocks.
(*note: asphalt can be laid in continuous strips because it's much less brittle than concrete, at least at normal service temperatures.)
"[Regarding the 'cloud,'] ownership was what made America different than Russia." -- Woz
Have you ever noticed that sidewalks are divided into little squares? I'm no expert, so there may be lots of reasons for it I haven't thought of, and it may not be the same thing at all. However, it seems to me it might be easier to get concrete to dry in little blocks than in one huge pyramid a hundred feet tall. Also, with heat/moisture, these things swell and shrink, and it's good to have a division so they won't crack and fall apart.
As a student at Drexel, I have had the privilege of hearing about this research firsthand - it is more than convincing. There is no doubt in my mind that he is 100% correct. For those of you in doubt - he is not claiming that all stones were "cast" or "molded" into places. Only the ones at the top and on the outside of most of the "newer" pyramids. The older pyramids do not use this technology. It is believed the egyptians discovered this technology as they were building and their pyramids became more sofisticated as a result. You can just look at the pictures:
r /BentPyramid/EgyptianPoliceman.jpg
r /AllPyramids/StaircaseInsideRedPyramid.jpg
i d.html?ref=science
The Bent Pyramid (an older pyramid), its obvious blocks put into place from a quarry up until where it bends.
http://www.richard-seaman.com/Travel/Egypt/Dahshu
Now, look inside the Red Pyramid (a newer pyramid), tell me they carved 26 million bricks with such perfect precision. They carved Limestone, using copper tools (ahem, softer than limestone), so perfectly together that you can't even fit a playing card between them? I don't think so.
http://www.richard-seaman.com/Travel/Egypt/Dahshu
This article can also be found on the New York Times http://www.nytimes.com/2006/12/01/science/01pyram
In all honesty, if you were to ask me to construct a pyramid today--knowing what I know, I would build the core of the pyramid out of laid brick.
A lot of the later pyramids actually were built with a core of laid brick, and cased in stone. These didn't hold up as well as the older, all stone pyramids, like the Great Pyramid, because the bricks were made out of mud and eventually turned to dust. Today, a lot of the brick pyramids basically resemble mounds of dirt and rock, with the original pyramid shape just barely distinguishable.
SpyDock: Scientific Python in a Docker container
The limestones they are talking about used to cover the pyramid to give it flat sides, and the only remains left at Giza can be seen at the very top of the middle pyramid in this photo. (FWIW, this is the pyramid of Khafre (Chepren) - next the the Great Pyramid of Khufu (Cheops), which has had all of its limestone block cladding removed.)
The third large pyramid at Giza (Menkare/Mycerinus, foreground in the group photo) was intended to be covered in granite cladding. ed
That reminds me of a great children's book I ran across a few years ago called Motel of the Mysteries. It was a comical take on what archaeologists might think of our culture as they unearth a 20th century motel. It really makes you wonder how utterly wrong our understanding of history may be. The one thing I remember best from the history of ancient Greece is that all of our knowledge of that culture is based on a single book and a few fragments.
I believe in de-evolution. God made the world perfect, man fell, and its been going downhill ever since!
Also, the bronze technology of the time was more advanced than anything known to Victorian civilization - Burton writes about the bronze chisel (found inside a pyramid or temple, I forget) that was harder than wrought iron when he's discussing the switch from bronze weapons to iron weapons in The Book of the Sword.
We know that the ancient Egyptians had bronze tools hard enough to work limestone. We have at least one example.
I don't know that this answers your question, but people spent millenia dry-fitting stones by hammering down the high points (with other stones) and then rubbing the stones together. (People still make precision flat metal this way for machine tools. It's called way-scraping. Sorry I can't find a better link.) The point being, when they got done you had two rocks that were sufficiently flat that when put together they were within a dozen thousandths of an inch of each other -- you couldn't fit a credit card between them, and sometimes not even a piece of paper. (Common paper is pretty close to 0.002"/0.05mm thick.) So if you do *that*, then put a smidge of mortar in there and put the 2000 ton block down on top of the mortar, that might be responsible for it being only the thickness of aluminum foil. Which is a good thing: the thinner the adhesive, the better the bond, generally speaking.
Nostalgia's not what it used to be.
The problem with explaining say, the Great Pyramid at Giza, is that given near-infinite wealth and all available modern technology, we either could not build it today or it would be extremely difficult.
From http://en.wikipedia.org/wiki/Great_Pyramid_of_Giz
Whether they can cast concrete or not, the idea that a civilization which did not even have the wheel could build a structure that was visually indistinguishable from the Great Pyramid, if they were willing to work hard enough to do it, could maybe be plausible. But the idea that they could have built such a structure, to those tolerances and with that degree of precision is laughable at best. The diamond-tipped blades typically used to cut large blocks of stone wear and warp (both due to mechanical stress and due to heat) during use sufficiently that they could not cut stone with that kind of precision -- to the casual observer the cut would look quite straight, but detailed measurements would not show the kind of tolerances found in the Great Pyramid.
Additionally, the Great Pyramid is currently aligned with true (not magnetic) North with only 3/60th of one degree of error; bear in mind the true North shifts position over time, therefore in the past it was aligned exactly. The king's coffer in the Grand Chamber is made of one solid piece of granite; microscopic analysis of the holes drilled into it indicate that it had to have been done with a fixed-point drill, using hard jewel bits and a drilling force of two tons. The measurements of the pyramid's features "coincidentally" yields, to a high precision, numbers such as the number of days in a year, the earth's distance to the sun, the earth's mass, the speed of light, the sun's radius, etc. See this link.
The Pyramid is far more mysterious than most people would have you believe. My personal theory is that civilization is cyclical just as every other aspect of nature, that is, that eons ago there were civilizations that existed and had high technology, probably superior to ours, which either eventually destroy themselves (and civilization) or are destroyed by polar reversals, asteroid impacts, or other such cataclysms. The idea that we are the very first people who have ever had computing power or nanotechnology is at best an unfounded assumption.
While theories etc. are fun, I honestly have to say that I have no idea how that pyramid got there. And from what I can tell, neither does anyone else.
It is a miracle that curiosity survives formal education. - Einstein
First off, your use of the work mould means you are either British or know nothing about concrete. The walls used to hold the uncured concrete are called forms.
Making adjacent blocks with tight cracks is blindingly easy.
First, pour one block. Start with a corner one. This takes (4) side forms.
Second, strip the forms. Clean them.
Third, set three forms, using the hardened block as the 4th wall. Pour this one.
Repeat steps 2 and 3 ad nauseam.
You could pour every other block, and come back and pour the ones in between.
They even had the technology to make all of the blocks line up straight - string. We use the same technology today.
Besides, making a sort of concrete from powdered stone and lime just to pour it at the bottom seems like a real bad idea - why not just carry the mud and forms to the top and save the effort of moving and aligning the final bricks?
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