Bent Pyramid
Description: The Rhomboidal Pyramid or the Bent Pyramid is one of the most unusual and remarkable monuments of Egypt. It stands out among other pyramids because of its unique rhombus-shaped form and almost perfectly preserved casing stones. It has two entrances, two funeral chambers, and there is a double slope of its outer faces - these extraordinary characteristics allow calling it “The Double Pyramid”. Because of the rare features, it establishes some kind of mathematical perfection and attracts the researchers from various fields of study. However, so far there is no generally shared idea among scientists why the Bent Pyramid is shaped that way.Alternative names: Rhomboidal Pyramid,Blunt Pyramid,False Pyramid,Southern Pyramid of Dahshur,Double-Sloping Pyramid.
Lepsius No: 56
Type: Bent Pyramid
Location: Dahshur
Country: Egypt
History of archaeological exploration
1763: Nathaniel Davison, an English diplomat, entered the Bent Pyramid through the north entrance and went a few metres down a descending corridor. He could go no further as the corridor was entirely blocked by a pile of rubble.
1799: Dominique Vivant Denon, a French painter, made some sketches of the pyramids at Dahshur as part of Napoleon's expedition to Egypt.
1839: John Shae Perring, a British engineer and Egyptologist, cleared the north descending corridor of stone rubble that was blocking access to the inner chambers and was the first to enter the Pyramid. The date of the opening of the inner rooms is confirmed by the inscription "Discovered October 20 1839” left by Perring on the wall of the horizontal corridor. The explorer cleared and accurately measured the Pyramid and also managed to clear about thirty metres of the west descending corridor. However, he was never able to locate the entrance on the Pyramid's western face.
1843: Karl Richard Lepsius, a German archaeologist and Egyptologist, carried out archaeological excavations of Egyptian pyramids, including the Bent Pyramid. He recorded the Pyramid in the list of Egyptian pyramids under number LVI (56).
1883-1887: William Matthew Flinders Petrie, a British Egyptologist, conducted archaeological studies and took some accurate measurements of the Pyramid’s exterior features. Petrie scrutinised the north entrance and the location of the locking 'door', but apparently went no further.
1924: Gustave Jéquier, a Swiss Egyptologist, carried out excavations at Dahshur. He started cleaning the Pyramid's interior, but soon abandoned the venture for some reason.
1946-1949: Abd el-Salam Hussein, an architect with the Egyptian Department of Antiquities and an archaeologist, worked at the Bent Pyramid for four seasons. He was the first to carry out a comprehensive study of it, clearing the upper chamber of stone rubble, where he discovered the stone floor. In search of Sneferu’s hidden tomb, Hussein dismantled the floor and the blocks beneath it, where he discovered that huge cedar logs once lay across the chamber and along the walls. He managed to clear the chamber floor down to the rock base, but found no artefacts. Opposite the chamber, in a hole, Hussein came across a well-preserved red graffiti bearing the name of Pharaoh Snefru. Hussein also cleared debris in a section of the west descending corridor about 32 m long. At the beginning of the corridor, mummies of an owl and bat were found in a box in the pit, which was later examined by Dr. A. Batrawi. Hussein also engaged the French Egyptologist and symbolist Alexandre Varille to explore the Pyramid. Hussein died suddenly in 1949 before sharing the results of his work, and his notes were lost.
1951-1955: Ahmed Fakhry, an Egyptian archaeologist, excavated the Pyramid and the surrounding complex for four seasons. He completed the work of clearing the west descending corridor where he discovered the Pyramid's locking block, the only known 'door' of its kind. However, most of Fakhry's reports focus on the Bent Pyramid complex. He excavated the upper and lower temples and part of the satellite pyramid. Dr. Herbert Ricke, a scientific expert at the Swiss Institute in Cairo, was commissioned to investigate the Pyramid and the complex. He carried out architectural studies of the newly discovered monuments and drew up their schematics. A. Fakhry's research also involved Dr. Hassan Mustapha, associate professor of geodesy at Cairo University, who reviewed the interior and exterior of the Bent Pyramid.
1964: Vito Maragioglio and Celesta Ambrogio Rinaldi, Italian architects, published detailed descriptions and large-scale drawings of the interior and exterior of the Bent Pyramid as a follow-up to their two-decade exploration of the Memphis pyramids. After a detailed analysis of its interior, Maragioglio and Rinaldi suggested that there was another pyramid inside the Pyramid, a smaller but steeper one. According to them, when the original pyramid reached a certain height, the inside of the structure sank down. The ancient builders erected a wider and less steep pyramid around it; however, as a result of one more subsidence and other design irregularities, they decided to reduce the slope of the sides of the upper part of the pyramid, and thus got its characteristic ‘broken’ shape.
Since the 1980s, the German Archaeological Institute in Cairo (DAIK) has been studying the site at Dahshur, where the Bent Pyramid is located. The excavations have concentrated mainly on cult buildings, auxiliary structures and other tombs of the necropolis.
1986: Josef Dorner, an Austrian surveyor, took measurements of the Bent Pyramid.
2001: Charles Rigano, an American Egyptologist, together with Andrew Bayuk and Brent Benjamin, authors of the ‘Guardian's Egypt’, obtained permission from Egyptian authorities for the first time after many years to visit the chambers of the Bent Pyramid, which was then closed to the public. After their visit, a detailed report on the Pyramid's interior and the first colour photographs were published at www.guardians.net/egypt.
2016: Gilles Dormion, a French architect, and Jean-Yves Verd'hurt, an independent researcher, conducted an architectural study of the interior of the Bent Pyramid. They published a book on the Pyramid in which they detailed its structural features and also demonstrated the possibility of a hidden chamber. They claimed the height of the upper chamber should be 13.90 m, not 16.50 m as commonly described in early reports by other researchers.
2018: Upon consent of the Egyptian authorities, a photogrammetric survey was carried out by the French company Iconem, commissioned by Label News for a documentary, ‘Pyramids: Solving the Mysteries’. The architectural consultant was the French engineer and architect Franck Monnier.
Field studies
2018: Upon consent of the Egyptian authorities, a photogrammetric survey was carried out by the French company Iconem, commissioned by Label News for a documentary, ‘Pyramids: Solving the Mysteries’. The architectural consultant was the French engineer and architect Franck Monnier. As part of the research, Iconem took thousands of digital pictures to digitalise the external surfaces and interior of the Pyramid. The project has made it possible to ascertain the exact height of the upper burial chamber and to get additional data on the timeline of its construction. Besides, new data has been acquired on the structural features and current condition of the Pyramid's surviving encasement.
Date: 2018
Researcher: Monnier, Franck
The aim of the research based on a new innovative technology, was to run an X-ray survey of the Bent Pyramid’s interior using muons, which are registered within cosmic rays that naturally and constantly hit the ground and are able to penetrate deep into any material.
In December 2015, a team from Nagoya University, Japan, installed a device consisting of 40 plates with a total area of 3.5 m² in the lower chamber of the Bent Pyramid. Each plate contained 2 muon-sensitive films. The plates were removed after 40 days, in January 2016, which corresponds to the maximum useful life of chemical emulsions under the temperature and humidity conditions existing inside the Pyramid. The films were then developed in a dedicated laboratory before being sent to Nagoya University for analysis. More than 10 million muon tracks were recovered with these plates: the internal structure of the Pyramid was reconstructed using muon particles for the first time. Indeed, the images obtained showed the upper chamber inside the Pyramid, located some 18 metres above the lower chamber, where the device was installed. However, the aim of the survey was primarily to find a supposed hidden chamber of the same size or larger than the upper chamber. The results obtained by Nagoya University offer no evidence for an extra chamber of this size.
Date: 2015-2016
Researcher: Scan Pyramids
Laboratory studies
In late 1947, a small wooden box was discovered under a stone in the floor of a built-up corridor inside the Bent Pyramid, containing a small intact mummy less than one foot (0.30 m) long, shiny dark grey, almost black in colour and in good condition. The mummy was stuck to the bottom of the box, some parts of its surface covered with lumps of resinous paint. Several small yellowish-brown insects (Gibbium psylloides, spider beetle) were found among these lumps. Just before the mummified remains were actually exposed, two objects were discovered:
1. A very soft white, easily disintegrated filamentous, most likely fungal mass. The hyphae studied could not be any older, they seemed too fresh and undamaged. Attempts to cultivate the fungus in two different environments failed.
2. A small piece of feather was found at another place.
The mummy had bird bones that were not arranged in an anatomical order. The bird was dismembered, however, each separate member was wrapped, it was whole, with soft tissue. The skeleton belonged to an owl referred to the Tytonidae family of owls. Also found were peculiar and very thin non-bird bones; besides, parts of at least five skulls were found wrapped together with bird bones. They have been identified as the skulls of greater mouse-tailed bats (Rhinopoma microphyllum). Nowadays, the species is found in large numbers.
The mummy is of particular interest because it is the only available example of an intact mummy from the beginning of Dynasty IV (around 5,000 years ago). Despite the great variety of animals mummified by the ancient Egyptians, this is the first mummified bat found. The condition and arrangement of the bones in the mummy rule out the possibility that the bats were consumed by the owl before it was killed. It can be assumed that the mummy was an offering symbolising the power of night flight, which may have been useful for the deceased's journey through the darkness of the unexplored afterlife. Unlike the later procedure, in this case the bird had its feathers ripped out completely and was deliberately dismembered before being wrapped.
Date: 1948
Researcher: Batrawi, A.
In 1949, upon request of the Egyptologist Jean-Philippe Lauer, four samples were taken to the laboratory for chemical analysis. The first two samples were fragments of casing stone from the Rhomboidal (Bent) Pyramid, and the other two were pieces of limestone mortar from the masonry of the same Pyramid.
Analysis of the casing stone samples. Two pieces of limestone having a reddish-brown and black surface. The analysis of the inside parts of this sample gave the following results: Silica (SiO2) - 9.54%, Ferric oxide (Fe2O3) - 1.55%, Aluminum oxide (Al2O3) - 2.92%, calcium and magnesium carbonates (CaC03 and MgC03) - 85.99%. It was found that chemically, the reddish-brown colour is mostly rendered by iron oxide. It is in contact with the surface of the stone so tight that, although different in colour, it looks like part of it. It is bright and almost crystalline and cannot be washed off with water or any other organic solvent, nor can it be removed with a stiff metal brush. This proves that it was formed slowly and naturally in situ. If it was artificially applied to the surface of the stone, it would be easily removed and also could not be detected in a crystalline state. Studies have shown that the black colour mainly consists of manganese dioxide, which also adheres very well to the surface of the stone. It was formed from traces of manganese salts found in the limestone beneath this structure. As this surface layer of the naturally occurring desert varnish in the two samples in question has a distinct thickness, it is obvious that these parts of the Pyramid must have been frequently exposed to plenty of rainwater.
Analysis of the mortar samples from the Pyramid masonry. The first sample is from the Pyramid casing. It is almost white on the inside and reddish brown on the outside due to the iron oxide, which is probably naturally deposited in situ in the same way as the varnish that forms on the outer surface of the stones of the Pyramid. The source of the iron salts here is probably related to both the mortar and the Pyramid stones. The second limestone mortar sample comes from the shaft in the Pyramid. It is reddish-white and heterogeneous in composition, i.e. it contains visible particles of different colours. Both samples are gypsum mortars. However, they contain calcium carbonate, silica, iron and aluminium oxides, which are not man-made additives but natural impurities in the source materials. Conclusions: a) The first sample was unevenly burnt, with a burning temperature above 200° C, resulting in 33.60% of the gypsum being heavily burnt and no longer absorbing water. b) The second sample was properly and evenly burnt at the exact temperature, so no anhydrous calcium sulphate was formed.
Date: 1952
Researcher: Iskander, Zaky
Between 1984 and 1995, more than 450 organic specimens were collected from monuments built in the Old and Middle Kingdoms. The most suitable samples have been selected for dating. The objective is to establish a radiocarbon chronology of the monuments. This chronology has been compared with the historical chronology established through the reconstruction of written sources. The analysis of 2 samples obtained from the Bent Pyramid suggests that the average age of the samples and presumably the Pyramid itself is 4133 years (ranging from 4121 to 4146 years). The reign of Pharaoh Snefru, to whom the Pyramid is attributed, is dated 2613-2589 BCE according to the chronology by P.A. Clayton (1994).
Date: 1984-1995
Researcher: Bonani G., Haas H., Hawass Z., Lehner M.
