Post by jadedsage on Jul 28, 2004 6:40:40 GMT -5
At last: the inside story
CT and laser-scanning techniques have combined to examine the mummy of a priest buried in Thebes 2,800 years ago, and to recreate his life and death. Nevine El-Aref stepped into the world of cutting-edge technology to see how the secrets were revealed
Since early this month, the British Museum's special exhibitions gallery above the old British Library Reading Room has been converted into a theatre with a 12-metre curved screen for the virtual viewing of the mummy of Nesperennub, an ancient Egyptian priest who served the cult of Khonsu in Karnak Temple about 800 BC. The technology is by Silicon Graphics Inc (SGI), of Mountain View, California.
The museum no longer unwraps mummies as it did in the past, and this interactive, 3-D visualisation has been brought about by non-invasive techniques. The tour inside Nesperennub's corpse probes his secret layers and reveals details of his age, lifestyle, appearance, state of health and how he was mummified. A number of gold shields, amulets and scarabs of carved stone ceramic and wax were also located on his body.
Nesperennub's coffin has been one of the British Museum's most treasured exhibits since it was purchased in 1899. Before being chosen for this ground-breaking experiment, the beautifully painted sarcophagus had rested peacefully since being sealed by embalmers shortly before burial in Luxor's West Bank near the royal tombs of the Valley of the Kings. The mummy was X-rayed during the 1960s, but the cloudy images showed only that the deceased was an adult in his early 40s.
Now computer technology, CT (computerised [axial] tomography) and laser-scanning techniques have allowed the mummy's inner secrets to be exposed. The visualisation of the body has been achieved by 3-dimensional volume rendering techniques developed by SGI, a process also used in medicine and in car and spacecraft design. Using a CT scanner, more than 1,500 cross-sectional slices, one millimetre thick each, were taken at the National Hospital for Neurology and Neurosurgery, London. It was the first complete ancient body to be fully rendered interactively in a 3-D volumetric form.
"This sophisticated software is already in use in oil exploration, weather forecasting, medical diagnosis and military training, but this was its first use in Egyptology," Zahi Hawass, secretary general of the Supreme Council of Antiquities (SCA), told Al-Ahram Weekly. Hawass said that unwrapping mummies, all that was available in the past, provided some knowledge but caused irreversible damage to the body and wrappings, with at best loss of context of all objects found within the bandages and at worst complete destruction of the mummy. This invasive technique was used to examine the mummy of Tutankhamun.
"In Victorian times, Egyptian mummies were unwrapped at public spectacles, which were invasive and ultimately damaging to the mummy," John Taylor, an assistant curator at the British Museum, said. "We are gathering information here without disturbing the casing or cartonnage at all. We can reveal so much more than the naked eye can see." Using the new techniques, SGI and British Museum experts embarked on a two-year process of discovery, dissecting the corpse and even probing deep into its spine.
In an interview with The Observer newspaper, Taylor said: "All we really know about a mummy from the outside is what the person's name is and what they did as a job. We can now find out what they looked like, how old they were, whether they were healthy and how they died." But what was really new was that Nesperennub could be used again and again as an experimental model instead of offering a series of static images.
Together the scientists and historians have discovered every detail of the dead priest's physical condition and burial. They know, for instance, that he had an abscess at the base of one of his teeth and that the embalming team who worked on him made rather a botched job. It is not possible to tell from the outside, but a burial pot was accidentally glued to the priest's head. "The team must have assumed no one would ever find out, so they just carried on and covered it up," Taylor said.
According to Afshad Mistri, SGI's director of marketing for advanced visualisation, the study also solved a mystery about Nesperennub's mummy. In the early 1960s, an X-ray of his remains revealed a dried placenta on his head. Scientists thought it was an umbilical cord. But the SGI images revealed the placenta to be a shallow bowl of coarse, unfired clay. "It is a most unusual object to find within the wrappings of a mummy," commented Mistri. But when the mummy's head is viewed in 3-D from different angles and under a variety of visualisation settings, an important clue becomes apparent. It was probably used by embalmers to hold the resin poured over Nesperennub's body as part of the mummification process. Perhaps they placed it on the mummy's head and apparently forgot to remove it after working on the body and left it stuck to Nesperennub's head. An area on the back of the head from which the skin appears to have been torn away may represent an unsuccessful attempt to prise off the lumps of resin that anchored the bowl in place. "Realising that the bowl could not be removed without causing further damage, the embalmers may have decided to proceed with the wrapping of the body, hoping that their mistake would pass unnoticed," Taylor concluded. "But it would not be the first or the last time that Egyptian embalmers made errors."
Yet there is one new mystery about this priest, who once officiated at rituals inside the temple of Khonsu in Karnak. In the process of creating a 3-D representation of his skull, the team discovered a small hole, like a bullet hole, near his brain.
"It is an anomaly," Taylor wrote in the book entitled Mummy: The Inside Story, which was published for the occasion. He added that because it appears to be destroying the brain from the inside out and yet it does not seem to be the cause of death.
Neurologists have suggested a variety of explanations, ranging from a tumour to a cranial form of tuberculosis, but nothing fits completely because there are no other signs of disease in the body. They also revealed that the deceased had a tooth abscess.
Passing over the shoulders and crossing on Nesperennub's chest, the CT-scanning located red leather tabs known by Egyptologists as "mummy- braces". Next to them were two other leather pendants in different forms, seen clearly lying on the chest.
A second pair of tabs was also visible at the sides of Nesperennub's neck, which might be a counterpart to those on the breast. "These tabs and pendants are of value to historians," Taylor said, adding that they often bore embossed inscriptions that named the Pharaoh who reigned at the time. "But the 3-D images do not tell us whether or not the tabs on Nesperennub's mummy are inscribed."
CT and laser-scanning techniques have combined to examine the mummy of a priest buried in Thebes 2,800 years ago, and to recreate his life and death. Nevine El-Aref stepped into the world of cutting-edge technology to see how the secrets were revealed
Since early this month, the British Museum's special exhibitions gallery above the old British Library Reading Room has been converted into a theatre with a 12-metre curved screen for the virtual viewing of the mummy of Nesperennub, an ancient Egyptian priest who served the cult of Khonsu in Karnak Temple about 800 BC. The technology is by Silicon Graphics Inc (SGI), of Mountain View, California.
The museum no longer unwraps mummies as it did in the past, and this interactive, 3-D visualisation has been brought about by non-invasive techniques. The tour inside Nesperennub's corpse probes his secret layers and reveals details of his age, lifestyle, appearance, state of health and how he was mummified. A number of gold shields, amulets and scarabs of carved stone ceramic and wax were also located on his body.
Nesperennub's coffin has been one of the British Museum's most treasured exhibits since it was purchased in 1899. Before being chosen for this ground-breaking experiment, the beautifully painted sarcophagus had rested peacefully since being sealed by embalmers shortly before burial in Luxor's West Bank near the royal tombs of the Valley of the Kings. The mummy was X-rayed during the 1960s, but the cloudy images showed only that the deceased was an adult in his early 40s.
Now computer technology, CT (computerised [axial] tomography) and laser-scanning techniques have allowed the mummy's inner secrets to be exposed. The visualisation of the body has been achieved by 3-dimensional volume rendering techniques developed by SGI, a process also used in medicine and in car and spacecraft design. Using a CT scanner, more than 1,500 cross-sectional slices, one millimetre thick each, were taken at the National Hospital for Neurology and Neurosurgery, London. It was the first complete ancient body to be fully rendered interactively in a 3-D volumetric form.
"This sophisticated software is already in use in oil exploration, weather forecasting, medical diagnosis and military training, but this was its first use in Egyptology," Zahi Hawass, secretary general of the Supreme Council of Antiquities (SCA), told Al-Ahram Weekly. Hawass said that unwrapping mummies, all that was available in the past, provided some knowledge but caused irreversible damage to the body and wrappings, with at best loss of context of all objects found within the bandages and at worst complete destruction of the mummy. This invasive technique was used to examine the mummy of Tutankhamun.
"In Victorian times, Egyptian mummies were unwrapped at public spectacles, which were invasive and ultimately damaging to the mummy," John Taylor, an assistant curator at the British Museum, said. "We are gathering information here without disturbing the casing or cartonnage at all. We can reveal so much more than the naked eye can see." Using the new techniques, SGI and British Museum experts embarked on a two-year process of discovery, dissecting the corpse and even probing deep into its spine.
In an interview with The Observer newspaper, Taylor said: "All we really know about a mummy from the outside is what the person's name is and what they did as a job. We can now find out what they looked like, how old they were, whether they were healthy and how they died." But what was really new was that Nesperennub could be used again and again as an experimental model instead of offering a series of static images.
Together the scientists and historians have discovered every detail of the dead priest's physical condition and burial. They know, for instance, that he had an abscess at the base of one of his teeth and that the embalming team who worked on him made rather a botched job. It is not possible to tell from the outside, but a burial pot was accidentally glued to the priest's head. "The team must have assumed no one would ever find out, so they just carried on and covered it up," Taylor said.
According to Afshad Mistri, SGI's director of marketing for advanced visualisation, the study also solved a mystery about Nesperennub's mummy. In the early 1960s, an X-ray of his remains revealed a dried placenta on his head. Scientists thought it was an umbilical cord. But the SGI images revealed the placenta to be a shallow bowl of coarse, unfired clay. "It is a most unusual object to find within the wrappings of a mummy," commented Mistri. But when the mummy's head is viewed in 3-D from different angles and under a variety of visualisation settings, an important clue becomes apparent. It was probably used by embalmers to hold the resin poured over Nesperennub's body as part of the mummification process. Perhaps they placed it on the mummy's head and apparently forgot to remove it after working on the body and left it stuck to Nesperennub's head. An area on the back of the head from which the skin appears to have been torn away may represent an unsuccessful attempt to prise off the lumps of resin that anchored the bowl in place. "Realising that the bowl could not be removed without causing further damage, the embalmers may have decided to proceed with the wrapping of the body, hoping that their mistake would pass unnoticed," Taylor concluded. "But it would not be the first or the last time that Egyptian embalmers made errors."
Yet there is one new mystery about this priest, who once officiated at rituals inside the temple of Khonsu in Karnak. In the process of creating a 3-D representation of his skull, the team discovered a small hole, like a bullet hole, near his brain.
"It is an anomaly," Taylor wrote in the book entitled Mummy: The Inside Story, which was published for the occasion. He added that because it appears to be destroying the brain from the inside out and yet it does not seem to be the cause of death.
Neurologists have suggested a variety of explanations, ranging from a tumour to a cranial form of tuberculosis, but nothing fits completely because there are no other signs of disease in the body. They also revealed that the deceased had a tooth abscess.
Passing over the shoulders and crossing on Nesperennub's chest, the CT-scanning located red leather tabs known by Egyptologists as "mummy- braces". Next to them were two other leather pendants in different forms, seen clearly lying on the chest.
A second pair of tabs was also visible at the sides of Nesperennub's neck, which might be a counterpart to those on the breast. "These tabs and pendants are of value to historians," Taylor said, adding that they often bore embossed inscriptions that named the Pharaoh who reigned at the time. "But the 3-D images do not tell us whether or not the tabs on Nesperennub's mummy are inscribed."
