(I hope I've got these right, I can't view them on this machine)
As a young man, Denys Stocks was obsessed with the Egyptians. For the past 20 years, this ancient-tools specialist has been recreating tools the Egyptians might have used. He believes Egyptians were able to cut and carve granite by adding a dash of one of Egypt's most common materials: sand.
"We're going to put sand inside the groove and we're going to put the saw on top of the sand," Stocks says. "Then we're going to let the sand do the cutting."
It does. The weight of the copper saw rubs the sand crystals, which are as hard as granite, against the stone. A groove soon appears in the granite. It's clear that this technique works well and could have been used by the ancient Egyptians.
Cutting Granite with Sand | PBS Online | NOVA Online | WGBH
Besides cutting clean surfaces on their granite, the Egyptians also drilled cylindrical holes into their stones. A hole eight inches in diameter was found drilled in a granite block at the Temple of Karnak.
"Even with modern tools -- stone chisels and diamond wheels -- we would have a tough time doing such fine work in granite," says Hopkins.
Stocks was brought along to test his theories about how the cores were drilled. Inspired by a bow drill seen in an ancient Egyptian wall painting, Stocks designs a home-made bow drill. He wraps rope around a copper pipe that the Egyptians could have forged. Hopkins and Lehner then pull back and forth on the bow, which is weighted from above. The pipe spins in place, rubbing the sand, which etches a circle into the stone. With the assistance of the sand, the turning copper pipe succeeds in cutting a hole into the granite slab.
Cutting Granite with Sand | PBS Online | NOVA Online | WGBH
With the aid of a bow drill and sand, the pipe has cut a circular hole into the stone. But how can the drillers get the central core out?
Stocks wedges two chisels into the circular groove. The core breaks off at its base. Stocks reaches in and plucks it out, leaving a hole behind not unlike the ones once cut by the Egyptians.
Cutting Granite with Sand | PBS Online | NOVA Online | WGBH
