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For years, Egyptologists have hotly debated how the enormous pyramids of ancient Egypt were built more than 4,000 years ago. Now, a team of engineers and geologists brings a new theory to the table – a hydraulic lifting device that would have floated heavy stones to the middle of Egypt’s oldest pyramid, using stored water.
The ancient Egyptians built the Step pyramid for Pharaoh Djoser in the 27th century BC, and was the tallest structure at the time, standing at around 62 meters (204 ft) tall. But how exactly the monument was erected, with a number of stones weighing 300 kilograms (about 661 pounds), remains a centuries-old mystery, according to the study published Monday in the PLOS One magazine.
“Many detailed publications have discussed pyramid-building procedures and provided tangible elements, but they generally focus on the world’s newest, best-documented, and smallest pyramids. Middle and New Kingdoms (1980 to 1075 BC),” said lead author Dr. Xavier Landreau, CEO of Paleotechniciana private research institute in Paris that studies ancient technologies.
“Techniques involved may include ramps, cranes, winches, articulated lifts, winches, pivots, or a combination of these methods,” he added in an email. “But what about the pyramids of the Old Kingdom (2675 to 2130 BC), which are much larger? While human strength and ramps may be the only construction force for small structures, other techniques may have been used for large pyramids.”
Using an interdisciplinary approach, the new paper was the first to report a system consistent with the internal architecture of the Step Pyramid, the authors wrote.
A complex water treatment system based on local resources would have allowed for the existence of a water-powered elevator within the pyramid’s internal vertical axis. Some type of float would have lifted the heavy stones to the middle of the pyramid, according to the study.
While the theory is an “ingenious solution”, some Egyptologists are not convinced as a more widely accepted theory is that the ancient Egyptians used ramps and transport devices to lift the heavy blocks into place, said Egyptologist Dr. Senior Professor of Egyptian archeology at University College London who was not involved in the study. Here’s what experts have to say about the new theory.
The Egyptian desert was once a savannah
By analyzing available data, including paleoclimatology, the study of ancient climates and archaeological data, the study team suggested that water from ancient streams flowed from the west of Saqqâra Plateau in a system of deep-water trenches and tunnels that surrounded the Step Pyramid.
Water would also have flowed into the Gisr el-Mudir – a massive rectangular limestone structure measuring 650 by 350 meters (2,133 feet by 1,148 feet) – which would have acted as a retention dam. This device, which was previously thought to be a fortress, a celebration arena or a livestock enclosure, would control and store water from heavy floods, as well as filter sediment and dirt so that it would not block the water passages.
The theorized water treatment system would not only have allowed water control during floods, but would also have “ensured adequate quality and quantity of water for drinking and irrigation purposes and for transportation or construction,” said study co-author Dr. Guillaume Piton, researcher. with the French National Institute for Research in Agriculture, Food and the Environment, or INRAE, based in Institute of Environmental Geosciences from Grenoble Alpes University.
The authors pointed out several previous studies who discovered that the Sahara Desert saw more regular rainfall thousands of years ago than it does today. Instead, the landscape would have resembled a savannah, which could support more plant life than the arid conditions of the desert. However, there is debate about when exactly weather conditions were wettest.
There may have been enough water to support a system like the hydraulic elevator, said Dr. Judith Bunbury, a geoarchaeologist at the University of Cambridge in London who was not involved in the new study. She pointed to previous searches that found rainwater gutters being built and used in the Old Kingdom, as well as previous research that looked at the diet of birds at the time, which consisted of wetland species like frogs.
“I think there is a fairly widespread belief that it rained more in the Old Kingdom, certainly in the early Old Kingdom when the Step Pyramid was being built,” she added.
On the other hand, experts debate whether there would have been enough constant rain to fill the structures that would have supported the hydraulic lift, such as the “Dry Moat,” a giant canal that surrounds the Step Pyramid and nearby structures, which the authors believe the collected water helped power the elevator when in use.
The Sahara’s greenest period probably ended in the early third millennium BC, according to Jeffreys. The low rainfall would not be able to fill the structures to the extent necessary for hydraulic elevation and, furthermore, would not be able to keep up with the loss of water in the structure’s limestone, added Dr. Fabian Welc, director of the Institute of Archeology. at Cardinal Stefan Wyszynski University in Warsaw, Poland. Welc was not involved in the new study.
“There was a flooding of the climate (seasonal – winter rains) in northern Egypt (also in Saqqāra) during the 3rd Dynasty (2670-2613 BC), but its intensity was relatively low. These rains, even filling the wadis (a dry valley except in the rainy seasons) with water, it would not have been possible to fill the dry moat even to a small extent… these waters would have been immediately drained by gravity to the bottom of the rock mass, about which there is no doubt (unless it was a biblical flood), ” Welc said via email.
The study authors agreed that it is very unlikely that the system was permanently filled with water and argue that it is more likely that flash floods of the time could have provided enough water to support hydraulic lift during the pyramid’s construction. However, more research is still needed to know exactly how much rainfall and flooding likely occurred during this period, the authors noted in the study.
This is not the first time the Nile has been investigated to see if it played a role in the construction of the pyramids. A study published in May found a dry branch of the massive river and theorized that the stream was likely used to transport huge blocks of limestone to multiple pyramid construction sites. There is also some evidence that the ancient Egyptians used hydraulics on a smaller scale, Jeffreys said.
Mysteries of ancient Egyptian structures
Researchers have not previously determined a clear purpose for the vertical axis within Djoser’s pyramid. Some later pyramids, such as the Great Pyramid of Giza, have shafts that are believed to have been used for ventilation, and it is possible that the inner shaft was also intended for lighting or to relieve pressure in the chamber below, Jeffreys said. But as the first of its kind, the Step Pyramid was an experimental structure that is believed to have begun as an experimental structure. mastaba (a flat tomb) and was built, so it is not yet clear exactly what its internal features were intended for, he added.
The shaft inside the Step Pyramid is connected to a 200-meter-long (656-foot-long) underground tunnel that connects to another vertical shaft outside the pyramid. The external well could then connect to a hypothetical water-carrying section of the Dry Ditch known as the Deep Trench, but more research is needed, the authors wrote in the study.
The inner shaft begins directly below the pyramid, near the center, where there is a granite box with a plug at the base. This box is believed to be King Djoser’s burial chamber, but instead the authors suggest that it was built for the purpose of opening and closing the hydraulic elevator, allowing water to fill the shaft when in use.
As for whether other pyramids were built using this method, Landreau said further investigation is needed. “It could be the key to unlocking the mystery of how the largest monoliths, found in pyramids like Khufu or (Khefren) were created. These monoliths weigh tens of tons, making it seemingly impossible for them to be transported using human labor alone. On the other hand, a moderately sized hydraulic lift can lift 50 to 100 tons. Exploring hidden wells within these pyramids could be a promising avenue for research,” he added.
Despite the more than 4,000-year-old mysteries surrounding the pyramids and their features, there is sufficient documentation that the ancient Egyptians used certain technologies, such as scaffolding and mudbrick ramps, to help build varied structures, said geoarchaeologist Bunbury, from the University of Cambridge. , although there is no documentation or depiction of a water-powered lifting device to her knowledge.
“I think people since ancient times have been inspired by the pyramids as a huge building project,” Bunbury said. “And they find it very difficult to believe that they were just built by ordinary people at that time, partly because they consider it to be a long time ago. …It’s puzzling that there were so many proposals for what could be a kind of technological innovation that were again abandoned, when we know that they had technical solutions for these things anyway.
“That doesn’t mean (the hydraulic lifting device) wasn’t used,” she added. “But there is a kind of Occam’s Razor of what is the simplest thing based on what we already know.”
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