The Great Pyramid Void: A Layman’s guide
a few days ago Keith Hamilton published an article about the great pyramid and the newly discovered chamber. I am posting it here.
Keith Hamilton
6th March 2023
In the above old image we are looking at the entrance to the descending passage of the Great Pyramid; the figures above give a good indication as to the size of the masonry used in its construction, especially the huge ceiling stones which cover the passage, which the top figure above is sitting on. Above this figure in the background we can see some pent beams that are often referred to as chevrons.
In the above more modern image we can see that another pair of chevrons sits on top of the pair visible in the last image. These were not the only chevrons to occupy this area, as fragments exist of other chevrons placed in front of these; the inclined support beds for these further chevrons can be seen middle right in the above image.
Flinders Petrie was probably the first explorer to examine these chevrons in detail, he reports;
“These blocks are much like a slice of the side of a casing stone in their angle; but their breadth and length are about half as large again as any of the casing stones. Their mean angle from 12 measures is 50° 28' +/- 5'. The thickness of these blocks is only 33 inches, and there are no others exactly behind them, as I could see the horizontal joints of the stones running on behind them for some inches. On the faces of these blocks are many traces of the mortaring which joined to the sloping blocks next in front of them. These were placed some 70 inches lower at the top, and were not so deep vertically. By the fragment left on the E.side, the faces of these blocks were vertical. In front of these came the third pair, similar, but leaning some 7.5° or 8° inwards on the face, judging by a remaining fragment. Probably a fourth and fifth pair were also placed here (see PL. ix.); and the abutment of the fifth pair shows an angle of 70.5° or 73° in place of 50°. The successive lowering of the tops, leaning the faces in, and flattening the angle of slope of the stones as they approach the outside, being apparently to prevent their coming too close to the casing.1
The above drawing is Petrie’s PL ix (I have enlarged the area containing the chevrons). This area has perplexed researchers for decades as to the function of all this skilful masonry work. Suggestions were made that these chevron’s diverted and relieved weight above the descending passage, which led to the suggestion that the masonry above this location would hardly task the massive ceiling beams which already protected the descending passage; moreover, the chevrons were limited to only a small area near the exterior, so why were the chevron’s not continued along the descending passage which would have a greater masonry load above them as it descended. This chevron feature above the entrance appears to be unique to the Great Pyramid; it being absent from other giant pyramids such as Khafre’s and Sneferu’s pyramids.2 These other pyramids seem to have no issue when it came to construction of their descending passages, so why was it a requirement in Khufu’s pyramid? The whole area appears to have an illogical function, and yet building such a device some distance from the base of the pyramid must have had a logical function for the builders.
An early attempt to explain the chevron area was by J.Bruchet who produced the fig 13 above, from his publication on the Great Pyramid.3 Here he attempts to link the area with the movable door described by Strabo.
A different suggestion would come from the publication by Gilles Dormion and Jean-Patrice Goidin.4 Here the authors would state;
“This space implies the existence of a second entrance superimposed on the first.”
They would further add;
“The existence of this corridor is also the only rational constructive response to the device above the entrance.”5
In their drawing above they see the chevron area as a manoeuvring room, in order that plates of stone can seal the upper entrance. They would suggest that this upper corridor would continue horizontally towards the Grand Gallery,6 the drawing for this idea is on the next page.
For location of Grand Gallery see Petrie’s Pl. ix on page 3. Here we see the horizontal corridor ‘F’ approach the top of the ascending passage, then inclining up towards the north wall of the Grand Gallery.
Dormion and Goidin would not be alone in suggesting a corridor from the area of the chevrons. Most readers would be aware of the work of Jean-Pierre Houdin, and in the image above we can see how he has a horizontal and ascending passage connecting to the area of the chevrons. Further reconstructions of his ideas can be seen below.7
The examples above are just a selection of ideas in connection with the chevron area; but the idea that a corridor might exist behind them has been known for decades, and so it might seem surprising that the authorities have not took a greater interest in this area.
Interest appears to have been revived in 2016 when a void was detected behind the existing chevrons by the ScanPyramids project. The above 3d reconstruction is from their 2016 report.8 The muography scans cannot provide much in the way of detail, but more a fuzzy image indicating a possible void.
So to try and obtain a clearer picture of the void, further detectors were installed in various positions from 2016 to 2019 in the hope of getting a clearer picture of this area. This latest muon study was published online on the 2nd March 2023, to coincide with the media announcement on the same day on the Giza Plateau.
The muon results indicated a NFC (north face corridor) behind the surviving chevrons as shown in their fig 5 above. The report states;
“The shape of the NFC defined as a rectangular cuboid was estimated to have a width of 2.02 ± 0.06 m, a height of 2.18 ± 0.17m and a length of 9.06 ± 0.07m. The NFC appears to stop at the South side and simulation confirmed that there is no structure with a cross section of more than 1m× 1m further on the South (Fig. 3c and Methods). The bottom plane of the NFC is located at Z=0.72±0.13m which corresponds to -20m from the ground level. The East-West central axis of the NFC is located at Y = 0.03 ± 0.04m, which is coincident with the center of the Chevron and above the DC. The distance from the North face of NFC to the North face of the Chevron is 0.84 ± 0.05m which is about the same thickness as the massive limestone block of the chevron that can be observed from the outside, suggesting the NFC would be located just behind it.”
It seems that the authorities acted on this report and introduced an endoscopic camera through a gap in the masonry under the lowest chevron. My understanding is that no drilling was required in this operation, which begs the question, why was this not done decades ago?
The endoscopic camera was placed through the arrowed gap above. The masonry blocks below the lower chevrons form a tympanum behind the chevron, and it seems that they would have to be laid first before the chevron was placed against it. The image below from the ScanPyramids project is the only view so far of the NFC
Here we can see further chevrons extending further south, where we come across a dead end, some 9m distant. Note depressions on end of chevrons, which may have held beams during installation.
Dimensions for the NFC are uncertain, but at some 2m wide it is not a cramped space and allows for several workers to comfortably move about. It is early days yet on this space and the data is very sparse, but it might be the case that the chevrons above are a direct continuation of the upper chevrons highlighted in the image below.
I don’t know how the authorities wish to proceed with the exploration of the NFC, but one would think that some of the tympanum blocks will have to be removed in order to gain access; the tympanum can always be repaired after exploration. The interesting thing is that the lower pair of chevrons when installed effectively blocked access to the NFC. The image provided by the endoscopic camera certainly seems close to the floor of the NFC. As illogical as the exterior chevron area appeared, this new discovery only complicates matters even more, so what was its function?
At a press conference on the 2nd March 2023 on the Giza Plateau, Zahi Hawass made the following statement.
“We cannot say it’s a corridor at all, there’s no way there is a corridor would be here, because down 7m there’s another corridor. Between the 7m and the tunnel we found today there is something important, in my opinion can tell us for the first time that the burial of Khufu is still existed and this is what we could discover. I do believe that the area between the tunnel found and the descending corridor it should be the real burial, this is my opinion only, the real burial chamber of Khufu should be underneath that tunnel. I’m sure, sure, in a few months from now we can see if I’m correct or not.”
From the above statement Hawass does not see the NFC as a corridor but more a weight relieving device similar to the pent beams above the so called relieving chambers above the king’s chamber, and so somewhere in the yellow bounded area (shown above) could be the real burial of Khufu.
But is there another possible explanation? The NFC looks to be quite a utilitarian space, something more in keeping of what we see inside the 5th dynasty pyramid of Neferirkare at Abusir. Here we have a similar horizontal corridor which leads to the king’s chamber; this utilitarian corridor consisted of pairs of chevrons along its length. Inside this construction corridor, the fine masonry which made up the walls and flat ceiling of the horizontal passage would be brought in and assembled. There is probably two reasons why it exists inside Neferikare’s pyramid; the first is that this pyramid was the largest of the 5th dynasty and they may have wished to give added protection to the passage below; or and as well as, to ensure that the superstructure construction was not held up. The substructure chambers appear to have been built from the inside out, so by building the construction corridor with chevrons first, the superstructure can still advance above, even though the fine masonry of the passage below had yet to be introduced.
Clearly this is not the case for the newly discovered NFC, however, it could still act as a construction corridor.
The above image is from Borchardt’s publication9 and shows a similar but badly damaged corridor, which covered the destroyed horizontal passage below. For more information see my guide on Neferirkare: unfortunately this pyramid still awaits modern exploration, as only two explorers have been inside, that being Perring who worked for Howard Vyse with the last visit being by Borchardt, who published his brief findings in 1909.
If the NFC was a corridor where did it go to? When you look at Petrie’s Pl.ix it would head to the north end of the Grand Gallery; this is the level when substantial internal chambers begin to be constructed, prior to this level we only have parts of the descending passage (which is mostly tunnelled through the rock) and the ascending passage to construct. Most activity in chamber construction starts at the north end of the Grand Gallery; from here towards the centre of the pyramid we also have the construction of the queen’s chamber and passage. The Grand Gallery is a huge construction, and of course at its south end we have the king’s chamber; so in this area we have a hive of building activity. At some stage the Grand Gallery and the king’s chamber will be roofed, which closes off access to the workers, but there might still be vast amounts of work still to be done. These constructions may have been built with excesses of rock left on their faces in order to protect them during construction; only after construction would the faces be dressed down: traces of this was discovered by Petrie who reports on the faint bosses left in the king’s chamber and the undressed area by the queen’s chamber door.
So we might have a situation where the major internal elements are built but closed from the outside world, and yet a vast amount of work still remained in the final dressing of all these spaces. Closed to the outside world, the only route for the workers would be down the descending passage and then climb up the ascending passage, hardly a user friendly route for the workers, never mind bringing in materials to do the job. It would seem easier for the builder to build a construction corridor from the north entrance direct to the area of most construction. Such a corridor would be beneficial to the area of main construction. For example, significant wooden scaffold might be required to dress the high places such as inside the Grand gallery; it might be difficult to turn lengthy items at the junction of the descending passage and ascending passage. Building such a construction passage to the Grand Gallery would not task the builders much, compared to the benefits such a corridor would over, be it improved ventilation, ease of bringing in material and removal of debris etc.
At the moment the NFC only extends some 9m, and we appear to have a blockage at its end, (see artist’s impression on page 11) so if this is the start of a construction passage we should expect it to continue past this blockage. The blockage itself might just be a blocked up corridor, and hence why the ScanPyramids detectors fail to pick it up. After the construction corridor had fulfilled its use, the builders would very likely fill the space with masonry for security reasons; one would not want to leave an easy route for robbers. The last 9m of the corridor which we see today may simply have been left unfilled due to time constraints, the priority being to fit the chevrons which we see on the outside today, which also seal of the construction corridor.
If this was a construction corridor how would it connect to the Grand Gallery?
In Dormion and Goidin’s publication they point out anomalies on some of the lowest blocks of the Grand Gallery’s north wall. Dormion would also mention these anomalies in a later publication by him; though the passage from the chevrons is omitted in this later publication.10 Overleaf we have fig 37 from Dormion’s later publication; here we can see that the lowest corbel is not developed on the north wall, with blocks 3 & 4 noticeably different: could these be a possible entrance into the Grand Gallery for our construction passage?
Any such construction passage may not have been entirely level throughout its length, but raised slightly by steps or incline to its required position.
This leaves us with the north end of the construction passage by the entrance; why was it necessary to continue the chevrons further north? The surviving ones today largely seal of the NFC so why continue them. Why not just cover the NFC with large blocks of masonry, which would not attract attention?
The Pl 3, from Piazzi Smyth’s publication11 shows the masonry joints of the descending passage wall directly below the outer chevrons. Generally the descending passage for the most part down to where the passage is tunnelled from the rock is constructed of large single blocks; only at its upper end do we see unusual jointing and the presence of two courses of masonry at the upper end: we also have a scored line present on both walls of the passage. Those of you who follow my guides know that I see the pyramid construction process as a two stage affair. The first would be the erection of the inner stepped core, which would be followed by the casing phase. It might be possible that the NFC was part of the inner stepped core allowing easy access to the interior of the pyramid. When it came to the casing phase of the pyramid, the outer chevrons would be fitted sealing the end of the NFC; but this seems illogical, as surely the descending passage below hardly needs any relieving given the little amount of masonry bearing down on it in this location. If they had filled the area with normal core masonry it would attract no interest; instead they used fine Tura chevrons, which Petrie describes as
“The sloping blocks are of remarkably soft fine- grained limestone, about the best that I have seen, much like that of the roofing of the chamber of Pepi’s pyramid.”12
It would be interesting to compare the stone of the Chevrons in the NFC to those visible on the outside. If the stone robbers had robbed the last pair of chevrons they would have certainly broken into the NFC. The chevrons of the outer casing phase of the pyramid may have had a different role altogether. In my Great Pyramid guide I suggested that they may have protected an elaborate inner door; Strabo’s statement about a moveable door is often used to refer to the casing stone covering the descending passage, but I think it could equally refer to a door behind the casing stone (in the north passage of the Bent pyramid we have clear indications of a door behind the casing stone: see my Bent pyramid guides). An elaborate moveable door might have required significantly more head height than was available in the descending passage; this would take up space in the large ceiling stones which protected the rest of the passage. Therefore in order to offer protection for this area they may have elected to use chevrons to reinforce the area.
Clearly it is very early days for the new discovery of the NFC, and it’s likely that removal of some of the masonry under the lower chevron will be required in order to access the space and discover the manner of blockage at its south end. Until then everything is very much a guessing game, but hopefully interesting times are ahead as exploration continues.
References
- The Pyramids and Temples of Giza. First edition 1883, page 53
- Though the good preservation of the Bent Pyramid casing might hide such a feature.
- Nouvelles recherché sur la Grande Pyramid. J.Bruchet, 1965
- Kheops: Nouvelle Enquete, Propositions Preliminaires. 1986.
- Ibid, page 63 & 65
- Ibid, page 69 & 71. Drawings on pages 64 &70
- Images taken from Article, Pyramides.over-blog.com in an article published 12 Mar 2011.
- ScanPyramids-First conclusive findings with muography on Khufu Pyramid. Press Release, Cairo, October 15th 2016
- Das Grabdenkmal des Konigs Nefer-ir-ke-re. 1909
- La Chambre de Cheops, G.Dormion, 2004, pages 174-180
- Life and work at the Great Pyramid, Vol 2
- The Pyramids and Temples of Giza. First edition 1883, page 54
