The physics of building the pyramids
How did the ancient Egyptians manage to move stone blocks weighing tons? Perhaps by tying logs around them, as physicists have suggested in recent years.
The first pyramids were built more than 4,500 years ago in Egypt, in the days when mammoths were still roaming the world, to serve as burial sites for pharaohs. They were one of the Seven Wonders of the Ancient World, and the only one of the seven that survived to this day. They are made up of huge stones, most of which weigh about 2.5 tons and some even reach 80 tons. The question of how they moved these huge stones and raise them remains controversial to this day.
The first pyramids were built of strong granite stones. As time passed, smaller pyramids began to be built and the quality of their construction diminished due to a transition to soft, cheaper limestone. Unsurprisingly, the ancient pyramids were better preserved over the years thanks to the quality of the building materials. Contrary to what is commonly believed, the builders of the pyramids were not slaves, but most likely paid locals.
One of the most famous and preserved pyramids is the Giza Pyramid, built of 2.3 million blocks of stone and its total weight is estimated at 5.9 million tons. Researchers estimate it took 20 years to build, so that the builders had to build an average of 800 tons a day. This raises the question: how did they manage to carry hundreds of stones a day, each weighing a few tons, without the help of electric cranes and air-conditioned trucks?
One of the theories suggested was that the workers dragged the stones onto sand that had been moistened with water from the nearby Nile River. According to this theory, the water reduced the friction between the stones and the ground by 40 percent.
Though this method may have been useful in Egypt, many pyramid sites are very far from any water source (e.g., in Sudan).
According to another theory, raised by John Bush in 1977 in a article he titled the Rolling Stones, the ancient Egyptians attached cylindrical pieces of wood to the stones on all four sides. And by doing so, they could roll them instead of dragging them, on surfaces they laid along the way ahead of time to make the work easier.
In August 2014, Professor Joseph West proposed a new idea. In his opinion, the builders tied logs on the sides of the large stones. He estimated that the logs should have been about 30 cm in diameter, just like those used by sailors on the ships that carried the building stones on the Nile.
Whether the Egyptians used one of the methods proposed by the researchers or not, there is no doubt that the construction of the pyramids is an engineering marvel. These are engineering projects that required thousands of workers and many long years. The result is one of the most resistant structures in the world!
(Translated and edited by N. Elias)
