From Giza and Saqqara the system extended through a network of obelisks distributed along the country's routes: Heliopolis twenty kilometres away, Tanis in the delta, Alexandria on the coast — Cleopatra's Needles, today in London and New York — and Karnak, six hundred and sixty kilometres to the south, with the most imposing obelisk complex in Egypt. All of the same material: Aswan granite, the same as the King's Chamber. All roughly twenty to forty-two metres tall. All crowned by a small pyramidion clad in gold or electrum. All founded on deep bases that put them in contact with the water table.
Archaeology reads them as commemorative monuments, symbols of the Sun's ray. But the anomalies are too many. Why all from the same quarry, hauled for hundreds of kilometres, when local granite was everywhere? Why all within such a narrow band of heights? Why all with the gold pyramidion on top? Why distributed along the communication routes and not concentrated in the religious centres?
The technological model proposes that the obelisks are piezomechanical granite resonators, tuned to the frequencies of the pyramids' acoustic-seismic system, that work as repeater stations. They receive the signal travelling through the crust, amplify it with the monolith's resonance, and re-radiate it locally. The gold pyramidion on top acts as an electrostatic concentrator — a lightning rod working at low frequencies — and turns mechanical vibration into an electric field that nearby devices can pick up. The band of heights is not aesthetic: it is the window in which a granite monolith resonates within the system's frequencies.
There is a proof by counterexample, and it is the unfinished obelisk of Aswan: forty-one metres seventy-five, twelve hundred tonnes, the largest ever attempted, abandoned halfway through the work because it cracked. A transverse crack in a monolithic resonator drops its quality factor by orders of magnitude and introduces spurious harmonics. It stopped working. The same logic as the unfinished sarcophagus of the Serapeum: two archaeological anomalies, the same pattern, the same technical explanation.
The complete model — the obelisks as the network's backbone, the pyramidion concentrator, the coupling to the water table, the entire four-level architecture of the Giza system — continues in Vol. 1, Chapter 18 «Giza, the machine».
This simulation visualises the model discussed in the book; sources and the full argument are in the chapter indicated.