The Complex Mechanics of Pyramid Doors YouTube 1

Pyramids are, at the most basic level, a building with an entry point. Much of the recent emphasis and debate on the pyramids has been on their overall intended design. But I am a simple man and I need a narrower topic. I was looking at these structural drawings of the Great Pyramid one day and thought to myself, were the pyramids sealed up tight with plugs or did they actually have a movable door, which suggests someone who knew the secret to If the pyramids did have doors, what would they have looked like and how would the process of opening and closing such a door actually work? Today we are going to look at the various ways in which a pyramid entrance could be sealed and examine the mechanics behind those claims. To help us understand the various engineering problems a door in a pyramid would have to overcome, I built this model of the northern passage of the Bent Pyramid and what it tells us is fascinating. If a pyramid did have doors, that implies repeated access, a very interesting concept to say the least. Our investigation into this topic will lead us to some fascinating subjects in the field of psychology of pyramid construction, that is, the way in which the intent of the original engineers can be deduced or guessed at from the physical stones themselves. Because there are so many pyramids with so many possible designs, I am going to focus the investigation today on the three pyramids of Giza and the Bent Pyramid at Dashur and explore three ways in which the idea of a door on a pyramid can be arrived at. The first is from an ancient historical source who just plainly says the Great Pyramid had a door on it. Then there is what I call the reverse from the inside method, which takes the known sealed off areas and walks backward through that process to the outside to see what, from a purely engineering and mechanical perspective, was possible to do at that point and what wouldn't be possible. Finally, we will look at some marks on the entryway of the Bent Pyramid and see what they can tell us on this topic. Once we sort through those three little methods and identify the most logical candidates, we will attempt to dig into a little bit of the mind of the pyramid engineer, a job title that has sadly been lost to time but that I hope to revive one day when I inevitably begin building tiny pyramids in my yard just to see if I can do it. The four pyramids in question were meant to either be sealed, partially sealed and partially accessed, or fully accessible. A firm answer on this question gives us a nice logical footing to be able to incrementally move forward into that final area of our video. This is where I will attempt to speculate on what the designer was most likely trying to achieve with that method, but we will only allow ourselves to speculate narrowly based on what we have been able to reason our way to previously. Let us start with a basic concept Pyramids were, for the most part, built one layer at a time, each layer being smaller than the previous layer and that margin controlling the angle of vertical rise. A good analogy would be to 3d printing today. A time lapse of the Great Pyramid would show that same consistent vertical rise like we see in 3d printing. This means that when the level of the pyramid had risen to the level of the ascending passage and entrance, these features could be built and worked on without the constraints of the roof and the walls that we have today. Blocks that are too large to now leave the pyramid via the narrow passages were set in place and then the walls and ceiling were placed on top of them, locking them under the bulk of the pyramid today. Keep this concept of open construction in mind because understanding it clarifies a lot of problems going forward. One of those problems that has to be worked through on the Great Pyramid before we can get to that of the door is that of the internal blocking at the time the pyramids were initially abandoned. So many years have come and gone, so many layers of abuse and destruction that figuring out how the final stage of closure left the pyramid is a difficult problem to solve. This was a core problem in pyramid construction that Egyptologist Flinders Petrie worked through in his amazing book Pyramids and Temples of Giza. Many of my initial thoughts and the starting point from this video came from his work and branched out from there. He argues quite clearly that if the pyramid were fully blocked up to the casing stones then there would be no need to have a door. However, at least two different ancient authors clearly state or imply a door or some steps to a door were present at Giza. Many thanks to the Aceta Project for allowing me to use their pictures from inside the Bent Period. Their sources are linked in the description. This video would also not have been possible without the excellent investigative work of Ken Hamilton and his paper The Bent Pyramid, The Layman's Guide Part 1 and 2. Both sources are linked below and I strongly suggest you go check them out. To fully understand both sides of the debate, we must first examine the earliest records that allege a movable door on the pyramid at all because, after all, that idea had to come from somewhere. These reports come from the ancient travelers and historians Strabo and Diodorus Siculus. Let's start with Strabo first. In his book Geography, we read the following. Strabo is referring to the Great Pyramid here. Remember, this was before the forced passage via Mamun's Tunnel that supposedly let the first outsiders in. If Strabo was making this up, how was he so accurate about what was beyond the stones? Had he seen inside other pyramids, perhaps the Bent, and knew that, generally speaking, there was a sloping shaft down to the underground chamber? In any case, he correctly describes what an ancient explorer would have encountered if they had opened a door on the Great Pyramid, passed by the carefully hidden passage to the King and Queen's Chamber, and then descended down to the subterranean vault. It seems as though Strabo believed that the subterranean chamber was the When we come to Diodorus Siculus, we don't get a description of the door per se, but we do get an interesting adjacent idea. In Diodorus' text, he is speaking not about the Great Pyramid, but of the slightly smaller Pyramid of Khafre. Remember, there are two entrances on the face of Khafre's Pyramid. There is much debate about if the lower one is original to the construction or a later robber's tunnel, so that is a topic for a future video. It is interesting to note, however, that Diodorus says this pyramid had steps cut into one side. There is no mention of any access point to the Great Pyramid or the Pyramid of Menkaure. I personally find the idea of steps and no mention of a door strange. If steps led to a certain casing stone and then just stopped, then any concealment would have been for aesthetic purposes only, as the entrance would have been apparent from where the steps ended. For this location, we had the following possibilities. The steps were original and led to either the upper entrance, the lower entrance, or both, or the entrance had been uncovered by the tile of Diodorus and the steps were cut into the casing to make repeated access easier. So in summary, we have a direct statement of a movable door at the Great Pyramid from Strabo, and Diodorus mentions steps going up Pyramid of It is, of course, not enough to take the word of ancient authors and historians on such a claim. The specific nature of the Diodorus and Strabo portions, along with the apparent eyewitness nature of them, does sound compelling, but we must dig deeper into the pyramid structure itself for corroboration. One of the reasons why people assume that the entrance passage was fully plugged are these holes cut in the floor. The idea is that they must have been cut by someone trying to plug granite plugs out. However, no matter what the plugs were made of, the floor would have been the wrong place to start. The floor is made of hard granite and the walls and ceiling are not. If there had been plugs in here, it would have made more sense to attack the softer walls and ceiling versus the floor. Further, as Petrie points out, any wholesale destruction of the entrance plugs would have chipped up the walls and ceiling and that is not observed. Lastly, if prior to the forced entry into the pyramid by the Arabs, someone had removed the plugs, it makes no sense why they would have stopped at the triangular concealment stone to the ascending passage that by chance fell loose during the digging of Mamun's hole. A Mamun story isn't the main focus of the video, but for this to be standalone, a brief summary is needed, focused on the topic we are covering. When the Arabs forced entry into the Great Pyramid around 820, they did so because there was no visible doorway. The pyramid's smooth white casing hid the original ancient entrance about 17 meters 56 feet above the ground on the north face. From below, you'd see nothing but a smooth stone. Mamun's men therefore began cutting horizontally into the core about 7 meters lower. They hacked their way in for roughly 30 feet before accidentally intersecting the descending passage, the ancient passage that slants downward toward the subterranean chamber. To me, this seems like an extraordinary bit of luck to hit on this without any clues, so perhaps they had more of an idea of where to dig than we currently know. Once inside, they followed the descending corridor downward and soon noticed the plugged ascending passage branching upward but blocked by large granite plugs. They chiseled through the plugs through softer limestone and reached the ascending passageway. Once inside, they followed the descending corridor downwards and noticed that the plugged ascending passage branched upwards but was blocked by large granite plugs. The Arabs only noticed this because they were able to see the triangular concealment stone had fallen off during their digging. This means that if Strabo had been inside the Great Pyramid and that his stories were true about the descending passage and the movable door, that no one at the time could see that there were granite plugs blocking an ascending passageway due to that concealment stone right here. The Arabs chiseled around the plugs in the ascending passageway through softer limestone and then reached the ascending passage and the Grand Gallery above, logically attacking the softer wall and not the plugs themselves. After exploring the interior, Mamun's team realized the ascending and descending passageways must meet somewhere higher on the exterior. They followed the descending passageway upward to its start, broke through the blocking stones from the inside, thereby revealing the original entrance from within. That last phrase, broke through the blocking stones from the inside, is a retelling of what the medieval sources said happened, none of them contemporaneous to the act itself. Therefore, with the added knowledge that Mamun's team had previously encountered granite plugs and dug around them via the walls, it is safe to say that while the original entrance was discovered via the inside approach, we have no evidence that it was plugged with blocking plugs meant to seal the entrance for good. We have to ascertain if the entrance was closed via solid stone plugs, or a cleverly concealed door easily opened from the outside, difficult to open from the inside, and was subsequently ruined in the attack from the inside. Combining this fact with the lack of broken or whole granite plugs being found at the site, it is most likely that the bottom end of the ascending passage and the entrance to the Queen's Chamber were plugged, but the entrance to the pyramid itself was simply concealed, leaving anyone who discovered it a clear and free passage straight down to the subterranean vault. The idea that the subterranean vault was meant to be found by those who knew the secret of how to open the pyramid door, would be the finest unspoken layer of psychological pyramid defense I've ever seen, and its failure may have contributed to the end of building bigger and more complex pyramids. At the end of this video, we will summarize what we have found, and I will present a frank discussion of this potential psychological pyramid defense strategy. When it comes to the other two Giza pyramids on the same question of original full entrance plugging, we find that the entrance to the second pyramid, Khafre's Pyramid, has red tinted plaster in it to conceal imperfections. Once again, as Flinders Petrie logically points out, any dragging of plugs down this passage would certainly have removed at the bare minimum the red tint on the plaster. If, therefore, the entrances to the pyramids at Giza were not originally blocked up, then the idea of a clever door like the one that ancient authors ascribe is becoming more possible. What, then, would such a door intrinsically have to have in order to have the ability to be opened from the outside, presumably by hand, and yet so perfectly conceal the entrance that for thousands of years only those who knew the secret to its operation could find it? To answer this question, we need to look at the pyramids that came just before the Great Pyramid and see how they handled this problem. Now, I'm just using conventional dates of the pyramids to count backwards to the previous ones, so you can save your comments about how all of these are 30,000 year old antediluvian masterpieces that the Egyptians thought out of the ice age with glowing bits of meteor from the Younger Dryas impact, and then furbished into harnessing free energy machines, because I will not be impressed. Taking the date of 2580 BC for the Great Pyramid, we will count back 10 years and get to the Red Pyramid, another 10 years and we get to the Bent Pyramid. So it's completely rational to believe that the lessons learned and the techniques refined during the building of the previous two pyramids at Dahshur could have easily been refined and integrated into the Great Pyramid within a single technical designer's lifetime, or in their lifetimes plus that of a protege. Now, at the Bent Pyramid of Sneferu at Dahshur, we find a structure with two entrances. Both entrances are above the ground level and slope down two chambers, one at ground level and one below ground level. One passage descends from the northern face entrance and one from the western facing entrance. The internal chamber is being connected by a passage near the center. We will focus on the first few feet of the northern entrance. This location is precious because it is one of the few where the casing stones are fully intact on all sides of the doorway. This allows a view of the door frame where we can start to gather information on how it may have been closed. Petrie used the physical evidence of this door frame to try and argue that just like Strabo had stated there was a movable door on the Great Pyramid, the Bent Pyramid could have had one as well. Sunken to the frame are two holes three to four inches in diameter. His use of the word apparently, when he speaks about this, suggests that the information did not come from his own personal measurements or that he could not get them accurately. He was as much a surveyor as he was an Egyptologist and is well known for his extremely exact and precise measurements. Therefore, he was getting these details from somewhere else and wanted to let the reader know that there was some uncertainty. At least that's my take on the matter. He was right to be uncertain about the depth because the western socket is actually seven inches deep and eastern is 11 inches deep and apparently someone has filled them with concrete after this 1964 study by Meragiaglio and Rinaldi that documented those depths. Petrie was under the impression that a door similar to that at the Great Pyramid by Strabo could also work here. The holes on either side of the frame would act as pivot hinges for bronze protrusions set into a stone door, the pivot location having to be carefully calculated to get the door to put just slightly more weight to the front of the door than to the back. This would have created a near balance where the back of the door would be forced tight against this notch in the ceiling and the front edge forced downwards. However, the near balance would have also made pivoting such a heavy stone physically possible for human beings to actuate with only their hands. This notch cut into the otherwise straight descending passage would have been where the back of the door fit into the ceiling of the passage and where another smaller upright wooden door that Petrie thought could have pivoted on hinges sat into the ceiling and floor, although the floor was destroyed and no such floor socket is visible. This is a novel and intriguing theory that attempts to bring in the historical claim of Strabo at the Great Pyramid as a solution to another pyramid problem. However, I see a couple issues with the theory and I will present you with those issues in a possibly a better way of explaining these structural anomalies. Petrie was a great and insightful Egyptologist who brought his ideas about pyramid engineering to the masses and displayed great humility in his ideas. I am simply able to benefit from having a hundred years of refined and added information at my fingertips to be able to build from. As the old saying goes, we stand on the shoulders of giants. The first reason why having such a carefully concealed door at the Bent Pyramid would have been futile would be this massive lintel stone over the door. If secrecy for the door was desired, then this stone should have been made to match the other stones, not stand out twice its size. There is of course the possibility that the entrance was not secret and no matter how it was closed, the lintel was actually there to mark the entrance and make it easier to find. In that case, any sort of stone closing the pyramid would have been for more aesthetic reasons than secrecy. I personally believe that the large lintel was a deliberate move to highlight the entrance since this is just one of two entrances to the Bent Pyramid, but once again, just my opinion. The second issue with this door would be installing it. If we are to believe that the closed door joint would need to be as tight as those in the rest of the casing period in order to hide it, the top of the door frame would need to be shaved down to a thin edge with a semicircle carved out behind it for the top face of the door to rotate back when it was opened. We have to realize that the face of the door would become a lever with an offset fulcrum at the hinge. As the bottom edge of the door was lifted up, this portion at the top of the door would have to pivot up and backward in an arc, a smaller arc than the one at the bottom edge due to being offset at the fulcrum, but still somewhat of an arc. As you can see, at the top of the door, the stone does not allow for this. Any flapped door that moved in this direction would instantly bind right here upon trying to open it. Then there is the issue of initial installation. If secrecy is the goal, then so are the tolerances from the door to the door frame that would allow it to be invisible. With those tolerances, it would not be possible to put one hinge of the door first into a socket and then pivot the other in if they remain as protrusions on the door. The door itself would hit the frame and never allow the bronze sockets to inset. However, if the sockets were placed in the frame first and the door set onto them, then that could possibly work. If the door had slots in it and was slid over the protruding bronze posts, that would be a functional hinge. However, there would still be the issue of the door binding. The final way this binding at the door could be avoided is if the top of the door was somewhat rounded, with the hinge directly below the widest point of the arc. This would allow the arc of the door to function like a rolling wheel, the hinge being analogous to the hub. This would be tricky since the curve at the top of the door would need to be proportional to the distance to the hinge in order for it to pivot cleanly. There is a hole in the floor right when you step through the doorway, and several other door designs by other authors and Egyptologists incorporate this hole into their model to try and solve some of these issues. A door design by J.P. Lepre shows a blunted pie wedge of a door that would have to swing inwards to open, taking advantage of both the notch in the ceiling and the missing part of the floor. The problem with Lepre's door would be that it would only open the distance the door itself could pivot into the roof here, requiring the visitor to do a U-shaped maneuver under the door. Aside from being a physically difficult motion to do, horrifyingly similar to the scenes from the Nutty Putty Cave, I just can't see the gap would be enough to make it practical. If the door were a slab, there would still be the issue with binding, combined with the added weight it would take to lift it up without a counterbalance rear of the hinge. The slab door proposed by Goyan has the same issue only in reverse, where the bottom of the stone is pushed inwards and then up where I assume it would be propped open with a post. This seems like too heavy and dangerous a door to be practical. We will now move back to the same scenario at the Great Pyramid, and then we will come back here to talk about how these various sockets and holes in the Bent Pyramid could have a different explanation other than as door sockets. At the Great Pyramid, we have a different issue. There is far too much damage to see any remaining door hinges, if they even ever existed. As we mentioned earlier, we know the original entrance wasn't apparent to the 9th century Arabs that dug in from lower down. The massive scar around the original door stems from this early Arab activity, but if you were to take the hypothesized door and socket setup from the Bent Pyramid and move it here, as long as the proper center of gravity and radius to the top to prevent binding was taken into consideration, this is the door that would both function and match the description in Strabo's book. It seems unlikely that Strabo would make up the one type of door that would actually allow a few select individuals in the know to open the pyramid and then access it. It's the one shape that could match the casing stone angle from the outside, and also incorporate a pivot, making the stone weight hold the door closed, and yet with minimal effort, 50 to 60 pounds pull, the door could pivot up and out of the way. A further evidence for this is that Strabo could correctly identify the internal structure that could be seen without knowing about the hidden ascending passage. What possible reason could ancient engineers have for allowing access to one third of the chambers of the pyramid, keeping the king's and queen's chamber secret? Before I answer that question, I think we should go and take another look at those holes and sockets in the northern passage of the Bent Pyramid. If they were not for a door, and I'm not saying they weren't, then what could they have been for? Let's start with those holes at the top that are of an even depth. The four inch difference in depth would allow a beam to be placed in the door frame. There are various other sockets and holes in the walls that I am hypothesizing could be used for mechanical advantage. A rope could be woven through those points in various configurations, then wound around a winch at the door. This winch could have been used to pull heavy items up and down the passage during construction, or to help lower in the plugs at the final stage. If something heavy other than plugs needed to be lowered down, think of how impossible that would have been in a narrow passage. Anything heavier than something a couple people could stop with their hands was in danger of sliding down out of control. The notch also makes sense when you think about how hard it would be to maneuver either a plug that needs to be about the size of the passage, or something else large rectangular down that passage. The notch in the ceiling means that a rectangular object can be brought up to a platform level with the door and then pushed straight in. When it reached the back edge of the notch, the center of mass would let that object then tip downwards and go down the passage. The back of the object could be hooked to a winch wound around that initial beam at the door frame high enough up out of the way that something could slide underneath it and not be in the way. Consider the angle of entry that would be needed without this notch. The object would have to be tipped up initially at an angle matching the descent of the passage. Any mismatch in angle would pinch a tight-fitting plug or other item. The floor could have been left in place until the passage was set to be plugged, at which point removing the top layer would allow the plugs to be tipped down the passage and stop there. Unless you wanted to plug the entire shaft, something would have to stop the plug's descent. The same thing would be the case with the entrance, where the missing floor would once again keep a door-sized plug from going down the shaft. The added benefit of the chamfer here means that the final depth plug could be carefully controlled. The finished plug would theoretically be inset at the bottom and then tipped back into the frame. If it wasn't flush, you could lean the plug back forward and take a slice out of the frame again. Little by little, you could slice away until you got the perfect fit. While this theory does conflict with the idea that the entrance was highlighted by the larger-than-normal lintel, I cannot resolve these competing facts in another manner. At the end of the day, I readily accept that I am learning in this journey with you, and perhaps I am simply ignorant of the perfect solution. I have not incorporated the Western passage into this theory, and there may be some merit in doing so in the future. At the end of the day, not everything will go nicely and neatly into a little package with a bow on it. This pyramid is a complex, detailed, and confusing piece of engineering that delights in being inscrutable. In summary, let us go to what I promised you, the portion of the video where I allow myself just a bit more leash than usual to speculate. I shall caveat my words by saying I do not like to speculate or make assumptions or thought experiments without a strong warning at the beginning. These are not actually facts, but rather an interpretation from past engineering choices based on my understanding of human behavior that goes far beyond the span of time. The human mind can be unknowable even between people who know each other well, so attempting to read the minds of the ancient is a risky endeavor. That being said, what I am going to tell you is just my opinion, but I will show you how I got there. Let us take for a logical foundation the single item of a movable door on the Great Pyramid as a fact for argument's sake. If the Great Pyramid had a movable door, albeit a door that was well hidden, what could that accomplish that a plugged passage could not? Well, the human mind is driven crazy by the forbidden, the unknown, and the obscure. That is probably why you are watching this video. Take for example the following scenario. You are walking in the forest and suddenly come upon a carefully camouflaged door settled into a mossy hill, no matter how you found it in the first place. That is unusual and novel and no doubt you may take a look. You go inside and are met with a short corridor and a blank stone wall. You say to yourself, this is very odd, why would anyone put a door in when it only goes a little ways? Surely something even better must be hidden behind this stone wall. Since the corridor ended with a blank surface, you have a finite amount of area to check for this hidden compartment. You eventually tap on the right stone and sure enough you find the compartment. Now imagine that same scenario, but after the first door you are met with a deep descending passage, hundreds of feet underground to a subterranean chamber. While you may still be confused as to where you are at and what this place is and what is its purpose, the first thought you have will probably not be, what am I missing? I need to hunt further. You have been presented with enough adventure after the tantalizing entry to at least not have the first thought in your head be, I need to start tearing at the walls to see if I missed anything. Finally, what would the result have been if the door had been just plugged? Think back to the pyramid. What the Arabs attacked was its solid plug surface. The fact that they were able to hit the internal structure at all means that they had some idea that they were generally in the right area. How the Arabs knew approximately which side and how far over to dig came no doubt from the knowledge that pretty much all other pyramids in the area had an entrance on the north side, midway between the sides. Here's my point. No matter what, someone was going to get in. If you knew they were going to get in anyways and you wanted to placate them without letting them know the true secret chambers inside, you would let them find another chamber, perhaps one deep underground where those chambers are usually found, and let them be happy with that. The idea that not one but two chambers were left hidden much higher up in the pyramid would be different enough from previous pyramids to prevent too much scrutiny. And honestly, until the Arabs blasted this tunnel into the side, it worked. The passages to the ascending chamber were still plugged and perhaps would even fool the Arabs if the stone covering the ascending chamber entrance had not fallen down. So there you have it. My total bit of speculation is that one explanation for putting a door in the Great Pyramid would have been to allow just enough access that the curiosity of explorers to satisfy just enough that they explored no further. But remember, it's just a theory. Thank you for watching.