When people learn about Hydra-Slide skidding systems many comment on how innovative this new technology is, and how it changes the way they think about moving heavy loads, and I smile and nod. Hey, I’m ok with people thinking we invented the idea. The truth is, people were jacking and sliding 5,000 years ago.
While our civilization has evolved incredibly, the methods used by the ancient Egyptians to haul the huge stones used to build the pyramids are essentially the same as we use to skid heavy objects today.
The Egyptians had to quarry rocks and make huge stones. Then they had to transport these stones from the site and haul them up the side of the pyramid as construction progressed.
The laborers were able to get the 2.5 – 15 ton stone blocks from the quarries to the building site by sliding them across a lubricated surface, one small step at a time with no pulleys, no wheels, and no iron tools.
They most likely dragged the blocks with wooden sleds and ropes. Some think that workers used quarter-circle wooden sleds that fit around a rectangular block. They attached the sleds to the block, and a crew of men rolled them along the ground.
It has been theorized than the stones were then transported up the pyramid with a system of simple sledges on tracks (round logs laid lengthwise so they formed rails) installed directly on the side of the pyramid. They must have reduced the friction between the materials, probably by using a water/oil lubricant. The stone would then be laid on a sledge made with round crossbars and skidded diagonally across the logs. Then a team of men, some behind with levers and some in front with hauling ropes would transport the stones over the lubricated surface.
Many improvements have been made to this concept in the last 5 milleniums… the modern skidding system uses hydraulic cylinders that push (or pull) shoes that carry a load over a controlled friction surface on a guided track, but the basic principle is the same… take a heavy load, whether it’s a stone to build a pyramid or a 500-ton vessel, put it on a reduced-friction track using levers or jacks, and push or pull the object using applied force. By doing this we reduce the amount of force needed to move something horizontally and can accomplish seemingly impossible tasks.
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