History
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2026-09-06 19:52:10 0381a5 | Anonymous | REF108 r1: new reference page on real flood-control machinery, companion to REF101. The world page now builds its mystery from a weir, race, drum, sluices and valves invented from scratch, and D019 expanded the project to many districts. Records the documented field: a polder has no finished state, only a standing obligation against permanent inflow; Kinderdijk's 19 mills (c.1740, UNESCO 1997) worked as a staircase because one mill could not bridge the height, lifting into an intermediate reservoir discharged only when the river was low enough - so districts can be stages of one machine rather than a list of places, and discharge is gated by an external cycle nobody controls; several real sluice gates (flap, fan, needle) run on water pressure with no external power at all, which is a free and authentic split in a design where power is the scarce resource; and draining peat makes it oxidise and sink, so water levels are lowered again, which causes more subsidence - 7 mm/yr at Polder Spengen, 2-4 m cumulative since medieval times, peer-reviewed. Two claims found in secondary summaries (the 1-1.5 m scoop-wheel lift, and Simon Stevin 1589) are deliberately omitted as unverified. Proposes nothing. |