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Originally Posted by geonuc
Two points, Henrik:
First, the general term 'pyramid' includes tetrahedron. So, Robert is correct in describing the object as interlinked pyramids.
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Thanks Geonuc, that was my intent, and I do apologise for my imprecision. I have been looking at information on the
Platonic Solids. The
dihedral angle of the octahedron is 109.47°, confirming your earlier comment 'if my trigonometry is correct, the 'slope' works out to be 54.74 degrees' and illustrating how magnetite forms a platonic solid. Of course the octahedron based on the great pyramid is compressed slightly at top and bottom by comparison.
Quote:
Originally Posted by geonuc
Although, why the isometric magnetite crystal was invoked to compare to this object, I can't understand.
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The connection is that in Egyptian mythology Thoth was reputed to have a role in designing the pyramids, and his Emerald Tablets are the source of the idea that the microcosm is a reflection of the macrocosm, an idea which is conveyed in symbolic form in the stellated octahedron. To tell the truth, I am not aware of any Egyptian use of the octahedron, nor of this two/three dimensional representation like the Star of David.
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Second, I believe a stellated octahedron requires the two tetrahedra to 'interlink' to the point where the vertices are described by a cube. In other words, that object Thoth is holding is not interlinked enough to be a stellated octahedron.
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Are you sure? It looks like there are eight small tetrahedrons around a central octahedron, so the shape seems to be made of nine platonic solids, but maybe my eyes are playing tricks. It would be
easy to build one to put on my Christmas tree.
Quote:
Originally Posted by Celestial Mechanic
But will it sharpen my razor blades?   |
Thanks CM, that takes me back thirty years! Checked this out
here and
here. What I was wondering, tangentially, is whether the isometric shape of magnetite causes it to be magnetic. If so, we could imagine all sorts of resonant vibrations from an octahedron based on the GP. As I recall, the Von Danikin/Geller/whoever spookiness was at the pyramid focus point of the King's Chamber, whereas I am wondering about the relation between the end points of an octahedron.
ETA
A friend has sent me the following comments
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Hey Robbie, A fantastic image (literally!) of the octahedron. And poetically spot on, because of course a hemisphere implies a sphere. I recall but have been unable to locate a copy I have of an article from an English newspaper of the 20's or 30's which mentions a system of passageways under the Giza Plateau - typical, eh? The evidence vanishes like morning dew - but you remind me of another unanswered question from Giza - namely, what to make of the unfinished chamber at the end of the Descending Passage, which not only has a half-excavated horizontal passage, but also a vertical 'well' in the floor, filled with rubbish from time immemorial. If I were Zahi Hawass (and I will be one day), I'd clean that out and see where it leads, eh what? Emerald Tablet here we come!
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