Empirical Earth · The Boomerangs — Flat-Earth Proofs That Backfire
The claim
“A telescope brings a vanished ship’s hull back, so there is no curve.”
What is measured
A 2 m viewpoint sees ~5 km to the horizon. Zoom magnifies but never raises that line, so a hull below it stays hidden, unless refraction (which needs a curve) lifts it. More on refraction and the curve.
What would show this is wrong
a partly-hidden ship whose hull is restored by magnification alone, with the observer’s eye at a fixed height; or a ship that stays equally hidden when the observer climbs from the beach to a 20 m gallery. Both tests are free, and either one would settle it.
Sources
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