Letters Editor, Smithsonian
900 Jefferson Drive, S.W., MRC 406
Washington, D.C. 20560
As a long time supporter of Smithsonian as well as an ardent fan of NOVA, I enjoyed reading the "Obelisk Mystery" article in the January issue. But, I was disappointed that the "mystery" was never satisfactorily resolved and the project was abandoned before its completion.
Since the Egyptians had developed a fair level of geometry and skill at math, and the invention of the wheel preceded the obelisks, a thought occurred to me that seems to have been entirely overlooked by your article and the NOVA group. The leverage required to stand the obelisk upright could actually be supplied by the obelisk itself.
To illustrate my theory, I built a miniature wooden model representing a 100 foot high obelisk 10 feet square at the base tapering to 5 feet at the crown. Such an obelisk in granite would weigh in at approximately 637 tons. Even at this weight, the amount of human effort involved to set the obelisk upright using this method should be infinitely less than that employed by the NOVA group.
At 16,000 lbs./sq. inch, granite's compression strength is excellent. I suggest that two granite blocks weighing approximately 6 tons each be properly shaped then tied to the bottom of the obelisk with their parting line positioned exactly at the obelisk's center of balance. Each block would act as a fulcrum and a piston. As the obelisk is "teetered" in one direction, the corresponding block would be lifted up, under which sand mixed with water, clay or some other combination of materials could be pounded in to support the weight of the obelisk during its next "totter." As one after the other end of the obelisk is pushed up and down, a retaining wall or flask of sufficient strength, would be required for support as well as to keep the sand bed from settling or shifting. This action effectively duplicates that of a mechanical or hydraulic jack.
The obelisk's center of gravity is approximately 40 feet from its base end, so the effort required to lift the opposite end of the obelisk plus its offset weight (at 2 feet)and the 6 ton piston would be approximately equal in weight to 10 men. Since the moment arm on the top, or long section of the obelisk, is significantly greater than that at the base end, the same amount of work could be accomplished with only 4 men plus any amount of energy needed to overcome friction.
For a 100 foot obelisk, the tower upon which the obelisk must ultimately rest needs only to be 40 feet high, which represents significantly less rubble than the ramps or sand container suggested in the article. Final rotation into its full upright position could easily be done using ropes and ballast or a guide-way approximately 25 feet high filled with sand. Slowly emptied, this fluid bed of sand would lower the base of the obelisk very close to its final upright position. A key element in accomplishing this task would be the strength of the granite piston/fulcrum blocks. The removal of one block and the securing of the other so tightly to the tapered obelisk shank that it could act as a hinge to rotate the obelisk without slipping, is key to the project's success. The problem is not so much one of weight, but of balance. This would allow the obelisk to assume an upright position to the point of contact with an alignment channel carved into the base block. At this point, all remaining sand grains could be removed from around and underneath the obelisk and from the top of the base block. If the angle of the rotation of the obelisk and contact with the base block were carefully enough calculated, loosening and removal of the upper fulcrum block could then allow the bottom contact point of the obelisk with the base to become the new fulcrum. Thus, the obelisk could then be tipped into its fully upright and final resting place using levers, ballast and ropes.
By employing such a method, I suggest that a 100 foot obelisk could be lifted and set upright within a reasonable amount of time by a crew of fewer than 50 men.
Edward J. Fraughton, Sculptor
Telephone: 801 254-3303
Fax: 801 254-6606