The ancient Egyptian god Horus, holding the fog nozzle of the evaporative cooling passage of the Great Pyramid.
Horus images : E3752 from the Louvre Museum and figurine of Horus DUT162 also from the Louvre Museum ; Paris, France, Hauteur : 9 cm ; Largeur : 2,7 cm ; Profondeur : 6 cm. Date de création/fabrication : Basse Epoque (664 - 332 BCE).
Evaporative cooling applications webpage screenshot : AquaFog® from Jaybird Manufacturing Inc (Pennsylvania, USA).
The surprising efficiency of the evaporative cooling process that created cold in the horizontal passage of the Great Pyramid of Khufu, is still used today in modern evaporative coolers
"Evaporative coolers lower the temperature of air using the principle of evaporative cooling, unlike typical air conditioning systems which use vapor-compression refrigeration or absorption refrigeration. Evaporative cooling is the conversion of liquid water into vapor using the thermal energy in the air, resulting in a lower air temperature." Source : Wikipedia
The Great Pyramid of Khufu at Giza was a cooling unit designed for the purest mineral form of natron manufacturing : the salt used by ancient Egyptians for Pharaohs Mummification.
The operating process of the "known" part of the Great Pyramid consist in creating cold inside the horizontal passage. For this, the "motor" is inside the grand gallery : the energy of a granite block falling from the top of the gallery is used to get a micro-droplets water fog that will initiate an adiabatic cooling effect in the horizontal passage. The cold is then stored inside the Queen's chamber and transferred to a sodium carbonate (pure mineral form of natron used for the mummification) production unit, that was installed on the flat roof of the pyramid.
When I started to work on the pyramid, like everybody, I have focused on the 3 key elements that are the grand gallery and the 2 ascending and horizontal passages.
The problem with the grand gallery, is that you can do pretty much whatever you want with it. There are no clues here to start.
But with the 2 passageways, things are different.
I first worked on the horizontal passage. Because we can find a lot of clues here. And every one of them are pointing into the same direction, the same goal : to deal with the effect of thermal stress (expansion joints, small blocks, sand behind the stones). Another clue is that all these elements are only found in the beginning of the passage, close to the gallery and the ascending passage.
Meaning that the thermal stress only occurred in that specific area.
The ascending passage was also easy to figure out. Because of the girdle stones and the polygonal interlocking way the blocks were assembled. It meant that for this passage, the stress on the structure wasn't about temperature changes but pressure and shocks. Another clue are the granite stone blocks, the granite plugs.
If we look closely to these stones, the 2 at the bottom look like they've never moved an inch, and they certainly didn't. These ones were really "plug stones". The kind of closing system you want to use for waterproof containers. You need 2 lids, not just one.
The last granite stone, is really different. It looks really worn out, like it had a really busy day.
To be honest, it took me some time to understand the all thing. The ascending passage was clearly under water, it was a well and it had to sustain a lot of pressure, coming from the inside of the well itself. The girdle stones are the ones that tell us this part : they are huge blocks and the well is entirely passing through them. The girdle stones are nothing else than belts around the well, they are forming a complete strapping of the well.
And what could have cause the pressure inside the well if not the granite block? The fall of the granite block inside the well, was causing it.
And then, we know what was the purpose of the grand gallery : pull up the granite block to the upper part of the gallery, and let it go and crash into the well.
Maybe every 15 to 20 minutes the granite entered into the well, and the water inside got pressurized and ejected towards the horizontal passage. Once inside the passage, the water was then used to cool the air the same way we cool down the air today with an evaporative cooler (or adiabatic cooling process) : the liquid water transforms itself in vapor by absorbing the energy of the air, and that air is then cooled down by the process. The cooling just happened every 15 to 20 minutes and was located at the real beginning of the passage.
That was why they had to deal with the thermal stress of the structure, the temperature was changing all the time. And we are not talking here about just a little cool down : when the air is very dry, the adiabatic process is very efficient and can result of a 15 to 20°C drop in temperature (please, see the Carrier diagram, further below).
Important news after review of the Sneferu pyramids : please read https://www.milleetunetasses.com/blog/
It is now unclear to me if any ventilation at all was really in place.
The main goal of the cooling process was to cool down the Solvay towers installed on the flat roof of the pyramid for the pure mineral form production of natron. There could have been a ventilation towards the subterranean chamber, or directly to the Solvay towers themselves by the Queen's chamber shafts.
The microdroplets fog mentioned in my theory is the famous Dendera Light Bulb. The Dendera Light reliefs are depicting how ancient Egyptians produced the cold (the spat venom of the snake of the reliefs), and that they used this cold to cool down Solvay-like towers for the natron manufacturing (the djed pillars of the reliefs). They even represented how the cold was transferred from the chamber to the tower : by the Queen's chamber shafts (the arms of the reliefs).
The double outline of the characters producing / offering the bulb light (or the snake), is the proof that it was cold production : they were having cold themselves.
The Great Pyramid of Khufu horizontal evaporative cooling passage. Elevation data (inches) : "The pyramids and temples of Gizeh", by Petrie, W. M. Flinders (William Matthew Flinders), Sir, 1853-1942 ; section 40 (page 66) : "Passage to Queen's Chamber"
Everything in the first part of the horizontal passage of the Great Pyramid is designed to reduce the stresses on the superstructure induced by multiple temperature variation cycles. It is difficult to say how long was the cycle, but let's say it was about 15 to 20 minutes. It means that during all this time, the first part of the passage had plenty of time to warm up back to the temperature of the grand gallery. And every 15 to 20 minutes, it was cooled down again. The problem is not the cooling down, but the endless cycle of cooling down and warming up again. That is what stresses the structure.
1/ The first clue : the horizontal passage
That clue, came from what we call today the horizontal passage. But actually, it is really not that horizontal at all. Inside this passage is a portion that is actually a ramp, a 32 meters long ramp with a 0,3% slope. And that puzzled me, because what the heck right. A ramp here?
And that ramp was not the only weird thing about it. There was, on the first half of the passage, many troubling things :
1/ the blocks were very small, and that is completely uncommon in all the pyramid, because it is the worst thing to do if in a "common structural sense" : you need to get every block resting on top of two different ones to maximize the strength of the structure. In that first part of the passage, every single block is perfectly fitted on top of another one, forming a continuous joint between them.
2/ These joints were not only continuous but also larger, and filled with a strange black filling resembling to resin or tar.
3/ Each side of the passage here, were also perfectly symmetrical to one another.
4/ Behind these blocks, we also discovered there was some sand.
That's a lot of uncommon things, and suddenly, I got it. Because, when you add up the fact that a few feet away you have the grand gallery, and just above of it something that is nothing else than a big water tank, and that is the King's chamber, you have water in mind now.
When I was younger, I used to have an air cooler, the one you just have to put water in it to get fresh air. And that was what this passage was all about. The slope was intended to get water flowing, very slowly, and evaporate itself. Because when the water transforms from liquid to gas, it does cool the air. It is actually called an air adiabatic cooling system. It doesn't cost a thing, and can be very effective when the air at the beginning of the process is very hot, and very dry (and that part is gonna be very important soon).
So know, we understand why we have so many oddities in the first part of the passage. This first half is where most of the cooling was taking place if we make some air coming from the very beginning of the passage. The joints, were expansion joints (large and continuous). The sand was here to absorb any expansion and distortion forces. The blocks were small because less susceptible to crack.
And at the end of the passage, we have a 50 cm step (that's a big step). But in fact that step is nothing else than a basin, for the water.
This water was here to accumulate and store the cold that was produced in this passage. Probably this basin was in fact covered with a wood casing, so it was perfectly waterproof.
This horizontal passage was designed to do 2 things : cool down the water temperature in the basin and let the air coming from the grand gallery, passing through the passage.
Because under the niche of the Queen's chamber was an air vent going to the subterranean complex allowing fresh air and cold water to flow to the complex.
The Carrier diagram, or "Carrier psychometric chart", is used for determining the temperature and humidity properties of a constant pressure air-water mixture.
The dryer the air is at the beginning of the cooling process, the greater amount of water it would be able to take, and the colder it is gonna get. For example, if you have an air at 10% humidity and you know you can get to 90% humidity, then the temperature can be cooled down from 25°C, to 11,5°C.
More details on the temperature necessary to cool down the Solvay towers for the sodium carbonate manufacturing (natron), on the Dendera post.
The snake symbolism and the fog nozzle
In previous posts, I have suggested 2 possibilities for the nature of the fogging nozzle that ancient Egyptians could have chosen to produce the microdroplets fog into the horizontal passage of the Great Pyramid, using the inclined well pressurized water : a spiral nozzle and an external needle. But I think they used another option.
We have already seen that the snake was the symbol of the microdroplets fog production, because of the way that the snake is projecting its venom when protecting itself.
So, if they would have wanted to depict that fogging nozzle, it would have been associated with the snake.
And that is precisely what they did.
The multi-needle fog nozzle of the horizontal passage
On most snake representations, particularly when associated with the Eye of Horus, we can find a perfect circular shape just under its head, nearly every time painted in vivid blue, obviously the color of water. On many of these representations we can see that this circle is implemented with 6 needles pointing towards the center of the circle and most of the time there is an additional set of curved needles in the center of the circular shape (picture above, on the right).
Most of the time, the needles aren't very sharp, but occasionally (like on the left photograph, below), they really are ; and that tells us that these needles were functional and not pure artistic decoration.
That element is the fog nozzle of the Great Pyramid and the lotus flower of the Dendera Light Bulb reliefs.
Modern firefighter fog nozzles. Thanks to Shah Bhogilala Jethalal & Bros, India (left) and Grenn Line Hose & Fittings, Surrey, British Columbia, Canada (right).
It looks like that the fog nozzle of the Great Pyramid of Khufu, was amazingly very similar to modern firefighter fog nozzles. These nozzles are designed to deal with a great amount of water : they are high capacity nozzles. It is hard to evaluate the amount of water that was injected in a matter of seconds into the horizontal passage of the Great Pyramid, but it could be around 500 liters, maybe.
It is also hard to say if the very sharp shape of the needles we can see in some paintings or reliefs of the fog nozzle depicted by ancient Egyptians, has to be taken literally or not.
The modern firefighter fog nozzle teeth aren't that sharp, but they don't have to produce microdroplets either. Their fog is not designed to immediately evaporate and create cold. So, maybe the needles of the pyramid's fog nozzle were really that sharp and pointy.
Snake stones in a chapel in Dendera and relief in the Temple of Edfu. These 2 reliefs are showing that the Dendera Light (first and second images) and the fog nozzle (second image, with the Dendera Light), were in some way connected.
The junction of the grand gallery, the ascending passage and the cooling horizontal passage of the Great Pyramid of Khufu at Giza.
Left : Great Pyramid of Khufu at Giza, entry to the the ascending passage (inclined well), viewed from the grand gallery. Top and center : Egyptian god Ra in his solar barque, by Ausir. Top right : wall relief of Apep, temple of Edfu (author : Rémih, on Wikipedia). Bottom right image from Wikimedia Commons, author : Soutekh67
The Apep myth is the representation of the inclined well operating
The key element of the evaporative cold production was the ascending passage : it was flooded and every 15 to 20 minutes, its waters were pressurized by the fall of the impactor, operated from the grand gallery. Every time it got pressurized, a small amount of its waters were ejected into the horizontal passage where the fog nozzle(s) was (were) set to create the fog of microdroplets that would evaporate and cool the air.
This sequential events are actually metaphorically depicted in the myth about Apep and its endless fights with Ra. For more on this part, please visit its dedicated post
The key element of the connection between the grand gallery, the inclined well and the horizontal passage.
This photograph was taken before 1910, and it is the only photograph I know that shows this part of the lower end of the grand gallery. In the foreground there is the beginning of the horizontal passage (the Queen's chamber would be on the right), then you have the abrupt cut-off of the smooth ramp sloping floor and the slot in the middle. In the background, there is the east ramp and the north wall of the gallery.
The "slot" in the middle of the cut-off, is not the result of an abrasion, but a real design made for a unique reason : it allows the connection between the well and the horizontal passage when the well is lined up with its wooden casing.
This layout is absolutely essential to the process and it was probably extended by a heavy wooden piece that would sustain the pressure coming from the well and let the air, and then the pressurized water coming through towards the unit that made the micro-droplets.
The forced ventilation is primarily intended to clear the air of the subterranean chamber where the work on the cement is done, and the cold water would be used to realize the experimental reconstructed stones.
The air is first cooled down at the exit of the micro-droplets unit and is immediately used to cool down the water that runs on the 32 meters ramp that ends up in the basin of the Queen's chamber where it would be even more cooled down by the copper serpentine cold exchanger.
Source: "The Great Pyramid Passages And Chambers" Volume 1, by John Edgar and Morton Edgar, Glasgow 1910.
2/ The second clue are the girdle stones : the ascending passage was an inclined flooded well
When you look attentively to the drawing of the Edgar brothers, showing the girdle imprints on the walls, floor and ceiling of the passage, you can see something absolutely amazing : these girdle stones were arranged in 2 sets of girdles, and that these 2 sets were positioned at a different angle to the vertical axis.
It is like the 2 sets of blocks are opening up to reveal a dormant breach. More amazing is that at the exact location where the breach is positioned, we can find a tiny squared imprint in the floor with a granite plug stuck inside !
Contrary to what seems to suggest all the ascending passage drawings mentioning the girdle stones, there is not just 3 or 4 of these huge blocks in the passage. Actually, the entire passage, from the G4 girdle (the lower of the usual girdles) to the lower part of the passage, is nothing else than 100% girdle stones. The fact is that when the Edgar brothers tried to understand the role of these girdle blocks, they couldn't make any sense of this lower part of the passage and all these girdles. They were only interested in finding distances between blocks in order to associate these distances to Bible or other historical events. Girdle stones from G5 to G14 are completely pressed against each other. They couldn't measure anything so they didn't talk about it (this is precisely what they wrote themselves), and they didn't draw them either. And since, everybody did the exact same thing.
The problem is that this part of the passage, from G4 to G14 is so more protected with these girdles, that it makes the usual ones look like insignificant.
If you want to understand the girdle stones layout, you need to understand that the passage was flooded and that the girdles were acting as an integrated strapping of the well.
The pressure inside the well was probably perfectly distributed on all its surface by a another complete wooden casing, that also allows the well to be waterproof. It is possible though, that the seal between the blocks was sufficient enough so that no casing was needed. Probably the center part of the floor casing part is thinner than the rest of it, and it makes a kind of gutter inside the casing allowing air and water to get out of the well, into the entry of the horizontal cooling passage.
The 14 girdle stones of the Great Pyramid of Khufu, indicating that the ascending passageway was a well, and that it was drained inside the Al-Ma'mun cavity towards the descending passageway and the subterranean chamber.
My guess is that this particular layout was designed to drain the well for the shutdown procedure of the pyramid : a small granite block would have been positioned in the small imprint, placed against the wall, directly next to the dormant breach. When time has come to shut the pyramid down, the granite block n°3 is lifted up to the top of the grand gallery one last time, unless this time there is no float anymore. When the block is released and enter the inclined well, it doesn't pop back up to the surface but sink to the bottom of the well with high velocity. When it hits the small block in the imprint, it reveals the breach and all the water is drained trough the cavity of Al-Ma'mun.
The restraining of Apep : the containment of the inclined well pressurized waters
We've seen that the Great Serpent Apep was a metaphor of the inclined well waters and that the fall of the impactor into the well pressurized it. The forces at play were so high that not only it was at the origin of some of the more impressive parts of the fights between Ra and Apep (the thunder noises, the rumble and trembling, etc.), but it also put the well on tremendous structural forces. That was the mission of the girdle stones : maintain the structural integrity of the well.
So, when we are looking at the restraint of the Great Serpent Apep, on the above image from Ramesses KV19 tomb, we are looking at the representation of the water that was restraint inside the well. The ropes are representations of the restraint, and the red elements in a inverted U shape, are the girdle stones : the upper girdles are actually 2 U-shaped half girdles stacked on top of each other.
3/ The third clue is the polygonal arrangement of the blocks of the ascending passage.
These blocks are displaying an interlocking layout revealing that the passage was also under a lot of longitudinal forces. If the girdle stones were set to counteract transversal forces passing through the ascending passage (from the inside to the outside of the well), the interlocking layout of the blocks reveals that the passage was also under strong longitudinal forces (from the top to the bottom of the well, and reverse).
On the left is the cavity of the Caliph Al-Ma'mun, in which the water of the inclined well (the ascending passage of the Great Pyramid of Khufu) was drained into.
4/ The Grand Gallery : the heart of the living pyramid
The way cold was produced into the horizontal cooling passage, is absolutely marvelous, really. Hear me out.
That part is actually a very tricky one. Because it requires 3 parts, and one of this part is moving constantly from one to the other one. And because one of them is in the air, and the other one is filled with water.
The first part is the grand gallery; and the third part is the granite block, the top one found in the ascending passage. That block was first moved up, from the lower part of the gallery to the higher part, and then it was simply released in the central part of the gallery, the gutter.
That gutter was completely covered with a wood casing, all the way down the gallery, and extended into the inclined well (the ascending passage).
When the block went down the gallery, it first pushed all the air contained inside the wood casing in front of it, that is about 56 m³ of air. At the lower part of the gallery, the air was then forced into the horizontal passage by a gutter inside the wood casing of the well. What was the role of this air, and if it was even really wanted, is still unclear to me.
Once the granite block hits the water of the well, this water get pressurized and some of it is propelled into the entry of the cooling passage. But before it can be vaporized into microdroplets of water, I think one step has to be added here.
Because pressurized water alone is not efficient enough to get a perfect vaporization of the water. They had to transform it into microdroplets. There are actually many ways of doing it : you can project the water onto something (a simple needle for example) or into something (like a low-pressure spiral nozzle which has a very large opening so there can't be any clogging happening), but like I said before, they surely used a multi-needles nozzle.
So now, we have everything we need to evaporate the liquid water into vapor for the air to cool down.
But what really happens to our granite piston block? How do you get it back?
Well, this is very simple : you just have to add to your block a floater. You put the block and a floater both inside a moving wooden casing, and it does make the trick. It is simple, very effective, and so beautiful. Just think of the roaring sound of the thing barreling down the gallery, and then making a huge exploding sound when hitting the water, for a few seconds later, very gently coming back to the surface. Grandiose !
Of course, when the mobile casing with the granite block and the floater hit the water, a shock wave is so generated. And this shock wave could have very much so damaged the well. That is why, all the way down to the bottom of the well, it is reinforced by four huge massive blocks, the girdle stones. These stones are so big that the well passes inside them, completely trough them, and they are designed to work exactly like a belt, or a metal ring you have on a wine barrel.
Image on the left and center : Funerary Figure of Duamutef. 400–30 B.C. Late Period–Ptolemaic Period. The Metropolitan Museum of Art, New-York. On view at The Met Fifth Avenue in Gallery 133.
The Grand Gallery layout replica of the Sons of Horus figures at the Metropolitan
The first photograph is one of the Four Sons of Horus figures, visible at the Metropolitan Museum of Art at New-York, and is showing a jackal-headed figure representing Duamutef, the god who protected the stomach of the mummies.
The half lower part of this image has been magnified and partially enlightened on the second picture of the figurine so that we can see clearly the different structures depicted.
My assumption is that what we have here is a complete representation of the grand gallery layout of the Great Pyramid of Khufu :
1/ The eastern and western ramps, with 2 hollow section rails by ramp
2/ The central gutter (painted here in yellow, but in blue in the Catawiki figure, above)
3/ The top platform, with what could be the axle beam for operating the 3 ropes
4/ The south wall of the grand gallery
5/ The opening of the antechamber (black line)
6/ The opening of the passage to the King's chamber (black square)
Please note that the 2 ramps are showing the same double lines as the ones found on the squared scarab amulet that we can see below. It would reinforce the idea that the wooden beetle was in fact a double beetle.
Funerary Figures of the Four Sons of Horus, with Imsety (human head) second from the left. 400–30 B.C. Late Period–Ptolemaic Period. The Metropolitan Museum of Art, New-York. Imsety is the only one with a human head, the three other Sons of Horus figures have heads representing a jackal (god Duamutef), a baboon (god Hapy) and a falcon (god Qebehsenuef).
The axle beam for operating the 3 ropes of the gallery, was inserted into the 2 holes of the platform
The second magnified image is from the figurine of Imsety, the god that protected the liver, and who was one of the Four Sons of Horus. This image shows the eastern and western holes of the platform and it also depicts that the axle beam ends were having tenons that would fit inside these holes.
If this draw of the platform is to be taken literally, that means that the main axle beam was placed onto that platform and that my first idea that it could have been situated further into the passage to the antechamber was wrong.
The Four Sons of Horus real meaning : the scarab team
Inside the grand gallery of the Great Pyramid, it was not 1, but 2 beetle scarabs that were operated. The question of knowing if they would be physically connected or not, is not so easy to answer, but I think they were.
Anyway, many or most of representations of scarab amulets, are showing 4 or 8 elements, and I think that the Four Sons of Horus are representing the team of the scarab beetle unit. That is the reason why the complete layout of the grand gallery is depicted on these Four Sons of Horus figures visible at the Metropolitan Museum.
The rectangular shape empty of any decoration on the base of the Ptah-Sokar-Osiris figurine (highlighted in red), indicates where was inserted the granite weight that transformed the caisson into a piston/impactor, that was projected inside the inclined well of the Great Pyramid of Khufu. The white arrow shows the area that was protecting the caisson from the impact with the water of the well (the ascending passage).
Photograph credit : Ptah-Sokar-Osiris Figure, 306–30 B.C. Metropolitan Museum of Art, New-York. On view at The Met Fifth Avenue.
The equipment inside the grand gallery : the scarab beetle
A wooden gantry, that I call "the beetle", was operated by 10 men on the ramps. 8 were inside the beetle and 2 were "flying crewmembers", operating behind the beetle progression (these men were in charge of forcing the latch-bolts inside the walls after the passage of the beetle, and they were responsible for inserting the security pins inside the long mortises when the beetle was lifted up).
Position 1 : the piston is secured on top of the grand gallery and everything is ready for a new operating cycle to begin.
Position 2 : the forced ventilation
The piston has been released and is rushing down the grand gallery inside a fixed wooden casing. The air inside the casing (about 56 m³) is pushed forward, and redirected towards the horizontal passage by the little cavity at the lower end of the gallery.
Position 3 : the pressurized well water and the evaporating adiabatic air cooling
The piston has hit the water of the flooded well and part of this water under pressure is redirected towards the unit (spiral nozzle or needle) that will transform the pressurized water into micro-droplets that would evaporate and cool down the air. That is an adiabatic air cooling system that can cool down the air up to a 20°C drop.
The pressure generated by the piston and the shock wave passing through the well are counteracted by a very complex and effective design, based on the girdle stones and the polygonal arrangement of the blocks. The well is completely lined up with wooden casing leaning on the girdle stones that forms a perfect strapping around it.
Position 4 : the piston is coming back up to the surface
Once in the well, the piston starts to sink before being pushed up towards the surface by the wooden float.
In the horizontal passage, the air is first cooled down at the exit of the micro-droplets unit and is immediately used to cool down the water that runs on the 32 meters ramp that ends up in the basin of the Queen's chamber where it would be even more cooled down by the copper serpentine cold exchanger.
The sarcophagus was a biosand filter (discontinuous) or biologic slow sand filtration (continuous) for drinkable water supply
Though the sarcophagus had been found in the King's chamber, it had really been used (most probably for months), as a slow biosand filter for drinkable water supply from the King's chamber that was a water tank. The sarcophagus was installed in the little service room just next to the antechamber (not accessible to public). Please, observe on the drawing below, how the north water supply duct has been bended to get to the sarcophagus before getting to the King's chamber.
Also, the pit inside the King's chamber was a water reserve in case of the chamber might get dry. It was a well : the sand filtration works with living bacteria, and they need to be constantly under water to survive. Otherwise, all the process of getting the filter back in track would take a full month period. The time necessary to get a new bacteria population strong enough to get drinkable water.
For the shutdown of the pyramid, the sarcophagus had to be moved in order to hide or destroy all the area around it, in particular the portcullis system and the limestone blocks around, that controlled the water flow getting in and the King's chamber shaft. The first thing to do was to empty all the sand and the coarse gravel it contained (around 0.78 m³) and it was probably thrown out directly into the grand gallery or onto the top platform.
Most of this material from the sarcophagus, and from the digging done around it and from other digging places that occurred during the shutdown procedure, ended up inside the horizontal passage , the Queen's chamber and the lower parts of the Queen's chamber shafts after the "explosive" opening of the King's chamber complex.
The granite sarcophagus in the Great Pyramid of Khufu at Giza was a bio-sand filter for drinkable water supply.
The equipment inside the grand gallery
A wooden gantry, that I call "the beetle", was operated by 10 men on the ramps. 8 were inside the beetle and 2 were "flying crewmembers", operating behind the beetle progression (these men were in charge of forcing the latch-bolts inside the walls after the passage of the beetle, and they were responsible for inserting the security pins inside the long mortises when the beetle was lifted up).
The crew members had to go down the grand gallery backwards, because this is in this position that you can deliver the most effective effort, using at full power your legs and your back against the backrest.
The wooden rails of the grand gallery
The "beetle" wooden gantry was constantly moving up and down in the grand gallery on water lubricated wooden rails, one for each ramp. These rails were made of the assembly of identical units of 3.198 cubits.
1 cubit = 0.5236 meter, or 52.36 centimeters.
Every single rail unit ends up with tenons that will be inserted in the floor mortises.
There were short mortises on the floor of the 2 ramps (1 cubit long) and large mortises as well (1.13 cubits)
Every mortise was fit for tenons of 2 different rail units.
The beetle operating procedure in the grand gallery.
1/ The beetle is on top of the grand gallery. The 2 ropes it is attached to are 100% rolled up around the winding beam and the piston is simply floating inside the well, its rope 100% unrolled and resting on the wooden floor of the platform at the top of the gallery.
2/ We need to get the piston back. So the first thing to do, is to drop its unrolled rope, inside the fixed casing. Now, we can reattach the end of the rope to the piston.
3/ The 10 men crew can then start to move the beetle down the gallery. The descent of the beetle allowed to raise the moving piston up to the top of the grand gallery, in 25 very demanding steps. They were going backwards, because this is in that position that you can deliver maximum pulling force, using your legs and your back. Every step was secured by 2 latch-bolts, one on each ramp, that were inserted inside the wall niches (2 x 25 niches, 50 niches total).
The latch-bolt is what you have on every single door you have at home. With this latch-bolt, you can slam the door closed just by pushing it, and it won't move again, unless you move the handle down. The 2 crewmembers at the top of the beetle were certainly the most experienced and were working with their eyes permanently turned to the latches, checking that it would correctly pop-up again once it had been pushed inside the wall by the passage of the beetle's slider.
4/ As the beetle is moving down the gallery, its 2 ropes unwind from the beam and the piston's rope winds up at the same time.
5/ The beetle is now secured at the bottom of the gallery by the last latch-bolt. Its ropes 100% unrolled on the ramp. The piston is secured at the top of the gallery, its rope is 100% rolled up on the beam.
6/ At the bottom of the gallery, a blocking slab shim is inserted between the beetle and the wall and it can now be released from the last latch-bolt.
7/ Before the release of the piston, the beetle first needs to be pushed up at the top of the gallery by
4 men, using the transversal beams of the beetle (2 on each side). 2 other men stay behind the beetle and secure the climbing with the safety pins they insert inside de safety mortises. 2 other men pull the ropes of the ramps from the top platform (1 on each side) and these 2 ropes then wind up automatically when the last 2 men of the crew unroll the piston rope on the wooden floor of the platform. The climbing of the beetle though, wasn't very challenging (there was nothing else to lift than the gantry itself), so the safety precautions were limited to one out of two steps. And this is why we have the long mortises : every two steps, a safety pin of 6.8 centimeters had to be inserted in it.
Of course, in order to push the beetle up to the top of the gallery, the latch-bolts had to be forced inside the wall. This could be done manually but I would say it was certainly fully automatic. Probably, the groove that had been made that runs through the entire gallery, was implicated in that process of forcing the latch-bolts inside the walls, and then back again out of the wall, ready for the next operating cycle.
8/ Both the beetle and the piston are now secured on top of the grand gallery. The beetle ropes are rolled around the beam. The piston rope is neatly resting on the floor.
9/ Everything is ready for the next cycle, the piston can now be unhooked from its rope and ready to be released.
When the piston is released in the gutter of the grand gallery and ends-up at the bottom of it, this central rope had to be pushed inside the fixed caisson so that it could be attached to the piston. This rope is pretty much constantly in contact with the water that is circulating inside the caisson for the lubrication of the glide, and is constantly wet. So, when it is put on the wooden floor of the platform, waiting to be pushed back in the caisson, it is dripping water all over the floor. And this is why the top stone of the floor had been adapted to collect this water and redirect it to the gutter. The collector didn't have to be pretty, because it was hidden by a perforated wooden floor.
The antechamber : a ventilated storage room for the 3 ropes of the grand gallery
This room was providing 3 drying and storage separated racks with 4 aeration pipes coming from the south grooved wall and the floor.
Photograph on the left : the 4 grooves south wall of the King's antechamber of the Great Pyramid of Khufu at Giza. Please notice that all the chamber is built with massive granite blocks, but surprisingly the top of this south wall is made of very worn out low-quality limestone. This limestone had been added after the pyramid shut-down, when this chamber didn't need to be connected to the exterior anymore.
If the elevation stopped at the top part of the Queen's chamber shafts, it also explains the grooves found in the Lady's Arbuthnot's chamber : they were the extensions of the grooves in the antechamber south wall. Inside these grooves were installed 4 air pipes for the ventilation of the antechamber. That ventilation was necessary to dry out the 3 ropes after being used in the grand gallery.
The 4 air pipes that were inserted inside the 4 grooves of the antechamber's south wall, were extended towards the Lady Arbuthnot's chamber. From this chamber, the pipes were connected to the exterior of the pyramid, passing through limestone blocks that have been replaced at the shut-down of the pyramid. Under this Arbuthnot's chamber, every block of the King's chamber complex is made of granite. Starting with this Arbuthnot's chamber, the granite blocks supporting the granite beams are replaced by limestone blocks.
The Queen's chamber and the copper serpentine cold exchanger
The Queen's chamber wasn't on the center line of the pyramid by accident. All the efforts invested by the grand gallery crew ended up in this chamber. Like every place in the above ground pyramid, it was (probably) covered in wooden casing that made the basin waterproof and the chamber completely thermo-isolated to keep the cold from getting out.
The Queen's chamber was designed to be a cold accumulator to cool down chemical reaction towers installed on the flat roof of the pyramid, for the manufacturing of sodium carbonate Na2CO3, the purest form of natron, by a Solvay-like process. Inside the chamber, a serpentine cold exchanger was set and might have filled the whole chamber. The serpentine was made of copper, and was connected to the Solvay towers by the 2 shafts of the chamber.
We can still see today at the back of the 2 first blocking slab stones at the upper part of both shafts, parts of these copper pipes.
On the front of these first blocking slabs, we see today that the pipes have been cut off and very neatly hammered down against the slabs and then flattened. These hammered pipes are called today "copper pins". We know it is copper (or mostly copper) because of the greenish coloration of it, resulting of the very hot and humid atmosphere conditions before the installation of the ventilation system in the pyramid.
But then, there is a problem. Because if the pipes inside the shafts have been neatly cut off, hammered down and flattened, only for the shutdown procedure, it means that the construction of the pyramid stopped pretty much on that level and stayed at that level during all the operation of the pyramid.
In this configuration, the operating pyramid was very easy to manage regarding the purpose of capturing rainwater, simply by dividing the flat roof in 2 separate watersheds, one for each King's chamber shaft.
The flat roof of the operating Great Pyramid
One of the most troubling things that I discovered if the theory is correct, is that the construction of the pyramid wasn't finished at all when fully operating. The construction stopped at the level of the upper part of the Queen's chamber shafts. It may seems wrong, but it makes actually perfect sense : there was a flat roof at the level of the Lady Arbuthnot's chamber.
With this configuration, everything is easier and more effective. For example, the operating pyramid was very easy to manage regarding the purpose of capturing rainwater, simply by dividing the flat roof in 2 separate watersheds, one for each King's chamber shaft. From the center of the flat roof of the pyramid, you could in a matter of seconds get to any of the entry shafts. You could open or close any of them, you could check if the filter on top of them was clogged or not. The surface of the watersheds created by this flat roof was gigantic and probably so effective that when the rain was heavy, you would have to let some, or most of it go. And that could be the reason why the apothems have been designed for : they were here to evacuate the overflow of the watersheds.
And there is more. Because there still may be the proof of that flat floor, visible today. That proof is inside the Campbell's chamber.
Inside this Campbell's chamber, on the west wall, there is a structure that looks familiar if you ever got interested in the crenellated block at the entry of the pyramid. Actually, it pretty much looks like a copy of it. A second crenellated structure. For me it strongly imply that the 2 structures were connected. They were working together. My guess is that inside the Campbell's chamber there was a filter to get rid of the sand and dust of the desert; and that clean air was then treated at the entry of the pyramid to get dehumidified. It was probably working with salt, that would have been easy to get rid off after use, directly to the subterranean chamber pit.
At the center of the crenellated structure at the entry of the pyramid, the left slot is clearly exactly the same than the one in the Campbell's chamber, and at the exact same place, on the left. But there is a big one that is missing in the chamber, and that is the one in the center (marked "6"). I think that this particular slot was assigned to the exit of the dehumifier.
I think the left trapezoidal slot was for the air intake. The air conduct started outside the south chamber's wall and was directed to the dehumidifier at the main entry. The second slot marked "6" at the entry was for the way out of the dehumidifier.
The shelter inside the grotto and the shutdown procedure of the pyramid.
We have seen that the real goal of the pyramid was a gigantic technological demonstration, and the same way a magician doesn't want to reveal his tricks, the creators of the pyramid didn't want to reveal theirs.
So, for the shutdown, a very complex chain of events had to be executed.
The easier part was to mask or hide as many things as possible, and for that a lot of little things had to be done, from the removal of all the wooden and copper parts, to the hammering of the top of the sarcophagus, or the filling of the niches in the grand gallery with mortar.
But the hard part was to make disappear as many clues as possible in the subterranean chamber, in particular the traces of smoke or organic chemicals on the ceiling, the walls and maybe more important of all, the pit.
For that reason, a huge operation had to be conceived and it involved the 2 biggest water tanks in the pyramid : the King's chamber and the Davison's chamber.
The plan was to release a huge quantity of water in a very short period of time, a wave of water and mud that would blend with some cement material in the subterranean chamber to cover as many things as possible in the chamber and make everything unrecognizable, deleting every clues there might be on the floor, the walls, the pit and of course, the ceiling.
To create the wave that would flood the subterranean complex, the King's chamber had to be modified because it was only designed to deliver a steady and continuous but low water flow. For that, the opening of the chamber had to be adapted and as important as that, the air intake of the tank had to be maximized in order to avoid a suction effect that would slow down the flow at best, but may also result in the implosion of all the King's and superior chambers.
For that matter, the air vent in the antechamber would have a very important role as it is directly connected to the outside of the pyramid, just a few meters away.
The block closing the passage between the chamber and the antechamber would be moved to the entry of the grand gallery and attached to the moving casing, resting at the top of the gallery.
Everything is now in place for the final act.
Probably one single man triggered the mechanism that ended the operation of the pyramid. He first climbed through the well shaft up to the granite block that has been installed at the upper part of the shaft, and pull the rope that is linked to the release mechanism of the moving casing at the upper end of the gallery. Probably one of the 2 holes of that granite block was designed for this purpose, and the rope was in place since the block installation. The casing is then released into the slope for its last voyage towards the bottom of the gallery. When there is no more slack in the rope which was attached to the temporary block closing the antechamber passage, the block is then ejected frontward and the water starts rushing out of the passage into the gallery towards the 2 wells.
The moving casing is for this time only naked, without it's float and at the bottom of the grand gallery, enter the inclined well, where it would sink and trigger the draining of the well, inside the Al-Mamoun cavity hole.
Some of the water enters the horizontal passage and the other part starts running down the shaft towards the grotto. The first part, in the horizontal passage would leave behind what it is called today "silt from the Nile" and the other part rushes through the well shaft.
After having pulled the rope, the man rushes to the grotto and it's upper shelter. Just above the grotto, and just bellow it, the shaft isn't inclined at all. It becomes fully vertical. This verticality is only there to avoid to get too much water coming inside the grotto. Some water, still manages to get inside and is neutralized by the pit while trigger man stands safely in the shelter, at the end of the upper part of the grotto.
The man is probably feeling some kind of anxiety coming to him. Because everything was planed a long time ago, but he is the one in the grotto ! The water is coming towards him. The granite block was designed to hold the water and the debris to avoid too much material to get to the grotto, where the pit will be able to neutralize some of it, but maybe there is gonna be more water than expected getting in.
So trigger man climbs up to the upper part of the grotto, wait and prey. Because this upper part has been designed for that precise reason. The upper part of the grotto is nothing else than a shelter. There were simply nowhere else to be for that final act.
As a matter of fact, the risk of a collapse of the King's structure was real, nobody couldn't be around the structure. And maybe it got close to the collapsing : a lot of granite beams where found with many cracks in them. It is said about these cracks that the beams didn't hold the pressure from the weight of the pyramid on top of them. I do not think so. I think they cracked because of the suction effect coming from the inside of the King's chamber.
Once everything has calm down, trigger man finally can get out of the grotto and out of the pyramid.
The final voyage of the grand gallery's piston (the moving casing and a granite block), triggered the release of the temporary block that was closing the end of the antechamber passage. Most probably one single man, did pulled the rope from the bottom of the grand gallery. He had then just the time to get to the shelter before the water got inside the well shaft. Fortunately, most of the water entered inside the horizontal passage because of its bigger opening.
Once released, the waters from the King's chamber forced the granite block n°3 through the inclined well and triggered its drainage through the Al Mamun cavity.
Mummy Board inscribed for Henettawy, daughter of Isetemkheb. Third Intermediate Period, Dynasty 21 ca. 990–970 B.C. The Metropolitan Museum of Art, New-York.
The Mummy board for Henettawy shows us the entire process of the Great Pyramid of Khufu operation
The lower part of the board is the lower part of the pyramid, the part we are familiar with ; and the upper part of the board is the upper part of the Great Pyramid, the one we don't have access to.
Like in the real pyramid, the 2 parts on the Mummy Board, are clearly separated.
• The lower part of the Mummy Board depicts, from bottom to top :
1/ The 3 rings that connected the moving caisson (1 ring) and the beetle scarab (1 ring for each ramp scarab) to the 3 ropes
2/ The "Nefertem copper pipe" supplying the "lotus flower" fog nozzle of the horizontal cooling passage
3/ The horizontal cooling passage itself
• The upper part of the Mummy Board, is showing the ultimate reason of the entire pyramid layout : the sand filtration of the 2 components we have already talked about in the Dendera post.
The final element of the display is the liquid dropping from the sand filter. It should most probably represent the Natron Na2CO3.
We've also seen in the Dendera post, that the 2 arms were representing the 2 shafts of the Queen's chamber. These arms are here represented 2 times, on the left and on the right of the board, I think each pair is for one shaft and that the 2 vertical lines descending from the arms represent 2 copper pipes that were connecting the Queen's chamber with the Natron production site on the flat roof of the pyramid.
The snakes represent the fog nozzle (again, please read the Dendera post for all the details about it), and they are supported by the arms : the cold (made by the adiabatic evaporation of the liquid microdroplets of the fog), was transmitted to the upper part of the pyramid (the flat roof) by the 2 shafts.
In the above picture, we can even see 2 grooves on the floor where air pipes might have been inserted in. This is the only picture I could find of the floor here, and I don't know if there are more than 2 grooves or not.
That part of the dehumidification of the air, as we are gonna see it later, is absolutely essential for the operating of the pyramid, both for the evaporating cooling in the horizontal passage and the drying of the 3 ropes used inside the grand gallery, the heart and the lungs of the pyramid.
The elevation of the pyramid stopped at the upper part of the Queen's chamber shafts (in pink on the drawing above). That explains the grooves found in the Lady's Arbuthnot's chamber : they were the extensions of the grooves in the antechamber south wall. Inside these grooves were installed 4 air pipes for the ventilation of the antechamber. That ventilation was necessary to dry out the 3 ropes after being used in the grand gallery.
The liquid dessicant dehumidifier inside the entry chamber
Today, this entry chamber doesn't appear like one, because there is only the south wall still in place. Most of the gabled roof has disappeared. Fortunately, the 3 other walls are still here, but misplaced : they are the 3 big limestone slabs. In that chamber, the exterior air was dehumidified.
Because the efficiency of the cooling process inside the horizontal passage was entirely depending on the dryness of the air getting inside the passage, it was crucial to dehumidify it before it got inside the piston of the grand gallery.
The dehumidification used a salt brine liquid dessicant : and asked for 2 different chambers: one chamber for the dehumidification process (the entry's chamber), and another one for the regeneration of the diluted salt brine : that would be the Campbell's chamber.
That Campbell chamber is very puzzling, because there are on its East and West walls, 2 different shapes of what could be water tanks. On the West wall, the tank is on the upper part of the wall and is leaning against the south ceiling. On the East wall, the tank looks pretty much like a collector of some kind and is located at mid height of the wall.
It is very troubling to think that some fluid was circulating inside this chamber. And because on the West wall there is also a trapezoidal notch, exactly the same shape at the left notch of the crenellated stone at the entry of the pyramid, that should indicate that fluid was also circulating inside what we should call, the entry chamber.
For some time now, I thought that inside this entry chamber, was a filter and dehumidification unit working with water (for the filter) and solid rock salt (for the dehumidification).
But the fluid circulating thing didn't match. It simply didn't work. You just needed to get rid of the water and the wet salt from time to time. No fluid circulation in there.
And then, I found out that even more effective than the solid dessicant dehumidification process, was the liquid dessicant dehumidification process. It may be troubling, but you can take the water out of the air (the vapor) by letting the air passing through a 50% salt concentrated brine.
Not only this liquid dessicant makes the dehumidification process more effective than with a solid dessicant, but it is also easier to use : the salt solution is also the filter solution that take dust and sand out of the air. When the solution is too dirty, you just have to discard it right into the descending passage, that is a perfect sewer.
And last, but not least : it also explain the Campbell's chamber.
Nowadays, the sea salt solution is replaced by more advanced kind of salt in the industry. But it works exactly the same. When the salt solution takes water out of the air, it becomes less and less concentrated, or more and more diluted. To keep the process effective, you must regenerate the salt solution. And that part occurs in another completely different unit, that is called the regenerator. Both parts, the dehumidification and the regeneration units are working completely separately, they are simply linked by pipes.
In the regeneration unit, the diluted solution is simply heated to evaporate the excess of water.
I think that the Campbell's chamber was the regeneration unit.
The diluted solution was pumped from the lower part of the dehumidification unit inside the entry chamber towards the Campbell's chamber where it got to the West wall by one of the 2 pipes we see the imprint on the floor (see photograph 2). It then got to the top temporary tank by the vertical extension of the pipe we also see the imprint on the middle of the wall.
From the temporary tank, it got to the trapezoidal section structure where the evaporation took place. The structure might simply have been lined up with solar heated copper tubes because at the time of the operating of the pyramid, this chamber was in open air, with the flat roof of the pyramid all around and plenty of space to install the heat accumulator system.
The East wall collector then redirected the regenerated solution to the second pipe on the floor, back to the entry chamber.
The question now, is to know why did the King's chamber shafts were extended after the shutdown of the pyramid. And I think it was because of the final act of the shutdown : the flooding of the subterranean chamber. With all that water inside the pyramid, it was necessary to allow a minimum of aeration to get all the humidity out of the structure.
Image on the right : Ptah-Sokar-Osiris Figure, 306–30 B.C. Metropolitan Museum of Art, New-York. On view at The Met Fifth Avenue.
The Scarab Amulets : the representations of the wooden gantry that was giving life to the Great Pyramid
The "forced entry tunnel" imputed to Caliph Al-Mamoun
In my theory, the Al-Mamoun passage has been built since the very beginning of the construction, and served as the real entry of the pyramid for all the subterranean complex.
Of course, it didn't have the same look as it has today, it was a perfect passage, like any other passage in the pyramid.
This passage started at the Al-Mamoun entry and ended inside the descending passage, passing under the horizontal passage. When the operating time of the pyramid was finished, all this passage was widened to prepare it for the shutdown procedure. The Al-Mamoun cavity and it's well was digged, in order to drain the flooded ascending passage and the water coming from the King's complex.
Finally, the main section was widened to facilitate the removal of all the equipment that was inside the Queen's chamber (copper heat exchanger and wood floor and casings) and the Grand Gallery (wood gantry and floors).
The construction of the pyramid without any ramp
This is a different approach of the way that the pyramid could have been constructed. I've never been fond of the ramp idea, because it takes time and a lot of efforts and material. Moving stones, even huge stones, is not something difficult at all. Every civilization in the world did use and moved huge stones when the stone technology was the more advanced of all. And none of them did need to build a pyramid to do it.
Moving or elevating huge stones, everybody can do it. I can do it, you can certainly do it. It is a just a matter of skills, not force. You can see on the internet a video (I'm sure many of videos exist, but one is enough for me), where a single guy, all by himself, 40 or 50 years old and a little overweighed, can move up a concrete block of maybe 10.000 kilos with only 2 beams and 2 buckets (water or sand, but it doesn't matter). And he elevated the block 2 or 3 meters high, without any sweat at all, just walking on the block with his 2 buckets !
Of course, there is a trick : each time he gets to one end of the block he has to come down and slide a beam the closest he can to the center of gravity of the block. This way he is elevating the block, step by step, pretty much like with a car jack.
So if this guy, alone in his backyard can do this, I'm not going to try to imagine something more complicated, like a grand gallery or whatever, to move blocks.
My idea is to use oscillating lifts, that actually do exactly the same thing that what that guy did, but better and faster because in a continuous way. It is constantly oscillating around the center of gravity of the block instead of a series of stop and go.
This method is very simple and effective to lift the blocks, but it is also a beautiful way to deal with the logistics. The blocks can be pre-positioned all around the pyramid on multiple layers, ready to be taking care of. By using this method, you can take advantage of the entire surface of the pyramid. The scale of the pyramid isn't a problem at all if you just have the manpower.
If we imagine that 4 crew members were operating a oscillating lift, we can start doing some calculations.
1/ 135 million lifts needed
We need to take care of 2.7 millions blocks. The pyramid is 200 stone courses, let's say it is a full cube of 100 courses : every block had to be lifted 50 courses in average. That is 135 millions lifts for the construction of the pyramid.
2/ 6100 oscillating lifts working at the same time
Let's say that an oscillating lift needs 4 crewmembers and 7.5 meters to work. The perimeter of the pyramid is 230 x 4 = 920 meters, so the average perimeter available is half of it : 460 meters. On these 460 meters we can fit 460 / 7.5 = 61 oscillating lifts. So for our hypothetical cube, we can have 61 x 100 courses = 6100 oscillating lifts working at the same time with 6100 x 4 = 24.400 workers.
3/ 15 to 20 years to build the pyramid
Lets say that every crew could lift a stone 3 times a day, that is 6100 x 3 = 18.300 lifts. If we need 135 million lifts, that would take 135 million / 18.300 = 7377 days for the lift of all the stones of the pyramid. 7377 days, that is 20.2 years.
Of course, if we need less than 7.5 meters for each lift or if we can lift a stone 4 times a day instead of 3, we won't need 20 years but closer to 15 years.
All the posts on the sodium carbonate and sodium bicarbonate manufacturing by the Solvay process, and its cooling in the Great Pyramid of Khufu : click here or on the "LE BLOG" button
The Dendera Light (English) : the "Light Bulb" is the microdroplets fog of the theory
Amazingly, the proof of pretty much every part of my theory, is carved in the Dendera Light Bulb reliefs : the fog of microdroplets produced inside the horizontal passage of the Great Pyramid, is the Dendera Light. The snake represented inside the Dendera Light Bulb explains how was produced the fog of microdroplets : the same way a spitting snake does when protecting itself with its venom.
The Disc of Sabu (English) : a counterflow chemical reaction perforated plate used in Solvay towers
Akhenaten and Nefertiti : why did they get rid of pretty much every single gods of their ancestors
The Scarab Amulets (English) : the complete description of the grand gallery's operating cycle
The Nefertem amulets (English) : the fog nozzle of the horizontal cooling passage
The Ptah-Sokar-Osiris figures (English) : the moving caisson / impactor of the grand gallery
The Great Pyramid of Khufu at Giza
The sarcophagus : a bio-sand filter for the production of drinking water
The horizontal passage : an evaporative cooling unit
The grand gallery : the heart of the operating cycle of the pyramid, with the wooden scarab
The shut-down of the pyramid : the grotto and the draining of the inclined well
The pyramids of Sneferu
Sneferu : the revolutionary quest for immortality
The Bent Pyramid : the chemical sand filter and the last trials before the Great Pyramid
Abstract (english) : "The Khufu's Great Pyramid Air Processing Unit"
The wooden base of the Ptah-Sokar-Osiris figures : the moving caisson / impactor of the grand gallery
The Nefertem amulets : the fog nozzle of the horizontal cooling passage
All the posts about Ancient Egypt & Updates on the theory : please click here