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    *Introduction

    *Episode1:
    Sand Pneumatics of Egypt
    *Episode2:
    An Overview of Mechanics
    *Episode3:
    The Mind of an Inventor
    *Episode4:
    The Mechanic's Community

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michaelpwilkes@ou.edu

Episode 1:
Sand Pneumatics of Ancient Egypt


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Imagine a crane, or a steam shovel, or bulldozer. They all use the principle of pneumatics to operate. Pneumatics use the principle of fluids in pipes of different sizes to generate a huge mechanical advantage. Take two cyliner pumps, one much larger than the other. When pumping oil from the small tube into the larger tube, the pressure exherted by the larger tube is much much greater than the pressure required to push down the pump on the small tube. These are relatively new inventions, or are they? In fact, the concept of pneumatics was used in the Egyptian days of pyramid building.

The Egyptians came up with the idea of pneumatics out of necessity while building the pyramids. Also, they used sand for the pneumatics systems rather than oil. The problem they faced was lowering a giant stone down onto a mummy in efforts to seal the mummy from grave robbers. Deep inside the tomb, there was a stone table. Upon this table they would place a mummy. This was an important individual in their society, perhaps a ruler. The objective was to seal this individual's body in such a way that robbers could not gain access to it. This was important because it was tradition to bury important individuals with many of their belongings, most of which were quite valuable. Also, the quality of the afterlife sometimes depended on the condition of the physical body. So the Egyptians spent a lot of effort to protect their deceased leaders. The Egyptians devised a way to place a mummy onto a table and to then lower a giant stone down over the mummy. This stone would have a hole carved out on the underside large enough for the mummy to fit into.
This way, when the stone was completely lowered, the mummy would be trapped in the carved out area underneath the large stone and sealed from the world. This stone was usually very large weighing many tons. It did a great job of sealing a mummy, but created quite a difficult task to get it properly placed. This is when the concept of the sand pneumatics came about.

The Egyptians first completed the pyramid, or at least the portion where the mummy will go. Above the stone table where the mummy would eventually be placed, there was an open shaft. This shaft was about 10 feet squared and many feet high. This shaft was filled with sand and then the giant carved out sealing stone was placed on the sand at the top. This stone was probably lifted up to the top in the same way the rest of the giant stones comprising the pyramid were lifted. Most historians imagine there was a sort of ramp system built all around the pyramid and then removed after completion of the pyramid. So using this ramp system the large block is placed on the sand filled column high above the table which will become its final resting place. In this particular pyramid, the top of the shaft rising from above the tomb chamber is actually about ground level so this giant stone lid would not need to be lifted up any ramps.

At the bottom of this column of sand, a few holes are made in the sides of the column. The sand comes pouring out from the sides of the pyramid and the large stone is slowly lowered down the shaft. This is the first of two stages of the sand pneumatic system. After the giant sealing stone is almost completely lowered, the Egyptians slow the descent and manually shovel out different sides of the sand filled column to guide the giant stone down onto four large wooden posts. These posts hold the stone about 3 feet off of the table. Each of these posts is a miniature version of the same sand pneumatic system. They each rest a few feet into a shaft that is just bigger than the posts. These small shafts are filled with a little more than 3 feet of sand. The table is swept free of all the sand. At this point, the mummy is finally slid into position on the table right under the center of the giant stone. Some personal belongings are placed next to him, other belongings are placed around the room.

To finalize the sealing of the the mummy, four people get into position around the stone and climb down to the bottom of each of the four small sand filled shafts. At the same time, they all pull small corks out of the shafts allowing the sand to start slowly flowing out and the giant stone once again begins to slowly descend towards the table. Each of the four people around the stone can cover their hole or dig out more sand to control the speed of descent of their shaft. With some coordination they all work to keep the stone level as it comes to rest upon the table. After all the sand is removed, the stone is completely resting on the table, and the mummy is very well sealed underneath it.

This main shaft is only a few feet wider and longer than the tomb, so it is almost impossible to get any kind of levers or systems into the shaft to try to remove the giant stone. Also, using sand instead of a liquid pneumatic system is actually better in this situation. One property of the sand is that it can be removed from a shaft to release potential energy, but is almost impossible to use it in the reverse form, pushing the block back up. Once seated, the pneumatics are usless adding even more security to the tomb.
Sometimes, this shaft is even filled with sand a second time and sealed so that any prospective robbers would have to dig through many feet of sand just to determine if a tomb is there. All of these features make the Egyptians masters at burial security.   (Every pharoah wants increased security from tomb raiders.)

The Discovery Science Channel ran a special episode about this very topic. I believe the name of the series was "What The Ancients Knew" and one episode in particular "The Egyptians" involved a team of about five people reinacting this scene of sealing a mummy in a tomb. (6) The group worked for about a week. They built a cement shaft and filled it with sand. They had a crane place the giant stone lid on top of the sand filled shaft and then worked only by hand from then on. They attempted to lower the large stone down onto a fake mummy to see if the sand pneumatics system would have worked. They let the sand run out to lower the lid down many feet onto the four wood posts, then cleaned the rest of the sand out. They then put the fake mummy onto the table and procedded to let the sand out of the four posts and let the lid all the way down. The project went quite well and the block was placed perfectly in place by only a few people moving sand around.

The tomb has evidence of this method being possibly used. The shaft, the posts, the large stone. There are some people who study this history that believe the entire pyramids may have been built using water pneumatics. They explain that the many shafts of the pyramids are not just air vents, they are water valves. Perhaps the egyptians attached boyant materials to the giant stones and filled the pyramid with water to lift the stones up to the higher levels. If the sand pneumatics is proven effective and the Egyptians used the theories, then perhaps they did use this pneumatic power to aid in all the building the pyramids.


 

Tom, the brave little adventurer has enterd the tomb of Pharaoh Manilo to get the fabulous wealth buried with the Pharaoh.