---
slug: the-tide-textbook-got-wrong
passed: 2026-10-14
by: the assay line (research/assay-line/queue-1014c/), Codex fixer directed by claude-assaying-boyle-1014; source record by Codex, checked by Codex
checked: 140
confirmed: 85
wrong: 27
unverifiable: 2
observed: 25
stale: 1
---

This was the directed repair pass for the tide layer read at f5e5f84f34. The fixer reported re-reading the evidence for all 31 triage items, retaining three rejected findings as CONFIRMED, and applying 28 fixes. The inventory also preserves the checker's 82 CONFIRMED, 25 OBSERVED and two UNVERIFIABLE claims from N2-codex.md as explicitly attributed results of that pinned source check, not a claim that this fixer repeated every historical experiment. Original claim wording has normalized punctuation; pinned arithmetic remains identified as pinned, while X19/X20 report the revised constants and their recalculation. The 17 MINOR lines count under wrong and have record-only dispositions. Seven dated corrections cover ten WRONG entries, with one shared lunar-speed correction. The sole STALE item is the dateModified metadata exception. This pass edited only this layer's files.

The 2026-10-14 repair follow-up confirmed the fix-checker's remaining X18/X27 speed-language finding and repaired the three copies in this layer. Two authored copies outside this layer remain under X18 open board notes. The 140 claim counts are unchanged; dispositions are now 26 [fixed], one [dated] and one open board notes.

## Claims

- CONFIRMED | The Sun pulls the Earth a hundred and seventy-nine times harder than the Moon does. | https://oceanservice.noaa.gov/education/tutorial_tides/tides02_cause.html; git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs | Checker result at f5e5f84f34, retained from N2-codex.md. [001 pull-179] NOAA says "more than 177 times"; this is compatible but not precise evidence for 179. Independently recomputed from the stated masses and distances: 178.862323717. See the independent calculation reported in N2-codex.md.
- CONFIRMED | The Moon raises the bigger tide. | https://oceanservice.noaa.gov/education/tutorial_tides/tides02_cause.html | Checker result at f5e5f84f34, retained from N2-codex.md. [002 moon-larger-tide] NOAA: "the moon is the dominant force affecting the Earth’s tides." This concerns tide-generating strength, not the tide at every port.
- CONFIRMED | the reason is one missing power of distance. | https://oceanservice.noaa.gov/education/tutorial_tides/tides02_cause.html | Checker result at f5e5f84f34, retained from N2-codex.md. [003 missing-distance-power] NOAA explicitly contrasts "inversely as the cube" with "inversely to the square". The inverse-cube tide is the leading spatial-gradient approximation, appropriate at Earth-Moon distances.
- UNVERIFIABLE | Almost everyone is taught the tides as two bulges | https://www.noaa.gov/jetstream/ocean/tides; https://schoolnova.org/sites/default/files/classes/6fb5jj90sb/ay2023/phy_3a/phy_3a-2024-01-21-file2.pdf | Checker result at f5e5f84f34, retained from N2-codex.md. [004 teaching-prevalence] The population quantifier is unsupported. Search: "tides" "almost everyone" "bulges". Positive controls found NOAA teaching the bulges and Schoolnova homework discussing the same teaching. Neither is a population survey. This is not a claim that no such survey exists.
- CONFIRMED | the Moon pulls the ocean into an egg, the Earth turns under it, and you get two highs a day. | https://oceanservice.noaa.gov/education/tutorial_tides/tides07_cycles.html | Checker result at f5e5f84f34, retained from N2-codex.md. [005 two-bulge-teaching] The clause describes the lesson, not actual tides everywhere. NOAA gives the conditional "If the Earth were a perfect sphere without large continents" and "every lunar day".
- CONFIRMED | it is a careful idealization that the real ocean ignores. | https://oceanservice.noaa.gov/education/tutorial_tides/tides07_cycles.html | Checker result at f5e5f84f34, retained from N2-codex.md. [006 idealization] NOAA: continents "block the westward passage of the tidal bulges" and establish "complex patterns within each ocean basin".
- CONFIRMED | Each correction is a number you can check | git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs | Checker result at f5e5f84f34, retained from N2-codex.md. [007 corrections-checkable] The three numerical demonstrations are present: the pull/tide ratios, opposite residuals, and equilibrium range versus observed Fundy range. The claim of checkability is supported; incorrect inputs and interpretations are adjudicated separately.
- CONFIRMED | Newton's law of gravity is an inverse-square law: the force between two masses falls off as 1/d². | https://oceanservice.noaa.gov/education/tutorial_tides/tides02_cause.html | Checker result at f5e5f84f34, retained from N2-codex.md. [008 newton-gravity] NOAA explicitly contrasts "inversely as the cube" with "inversely to the square". The inverse-cube tide is the leading spatial-gradient approximation, appropriate at Earth-Moon distances.
- CONFIRMED | Direct pull on Earth (∝ M/d²) 179× | git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs | Checker result at f5e5f84f34, retained from N2-codex.md. [009 panel-pull] Independent arithmetic gives pull ratio 178.862323717, distance ratio 389.172400364, and tide ratio 0.459596630052. Their identity holds before rounding. The published run prints "ratio = 178.9" and "ratio = 0.460".
- CONFIRMED | Tide raised (∝ M/d³) 0.46× | git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs | Checker result at f5e5f84f34, retained from N2-codex.md. [010 panel-tide] Independent arithmetic gives pull ratio 178.862323717, distance ratio 389.172400364, and tide ratio 0.459596630052. Their identity holds before rounding. The published run prints "ratio = 178.9" and "ratio = 0.460".
- CONFIRMED | tide ratio = pull ratio ÷ distance ratio = 178.9 ÷ 389 = 0.46 | git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs | Checker result at f5e5f84f34, retained from N2-codex.md. [011 ratio-identity] Independent arithmetic gives pull ratio 178.862323717, distance ratio 389.172400364, and tide ratio 0.459596630052. Their identity holds before rounding. The published run prints "ratio = 178.9" and "ratio = 0.460".
- CONFIRMED | it is the difference in the force across the width of the Earth, the near side pulled a little harder than the far side. | https://fr.wikisource.org/wiki/%C5%92uvres_compl%C3%A8tes_de_Laplace/M%C3%A9moire_sur_le_flux_et_reflux_de_la_mer | Checker result at f5e5f84f34, retained from N2-codex.md. [012 differential-force] Laplace: "la différence de ces forces et par l’inégalité de leurs directions." The surrounding paragraph compares the attraction on a sea molecule with that on Earth’s centre.
- CONFIRMED | Differencing an inverse-square law turns it into an inverse-cube one: the tide-raising effect goes as M/d³. | https://oceanservice.noaa.gov/education/tutorial_tides/tides02_cause.html | Checker result at f5e5f84f34, retained from N2-codex.md. [013 inverse-cube] NOAA explicitly contrasts "inversely as the cube" with "inversely to the square". The inverse-cube tide is the leading spatial-gradient approximation, appropriate at Earth-Moon distances.
- CONFIRMED | The Sun is about 389 times farther than the Moon | https://oceanservice.noaa.gov/education/tutorial_tides/tides02_cause.html; git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs | Checker result at f5e5f84f34, retained from N2-codex.md. [014 distance-389] NOAA rounds to "390 times further"; the stated astronomical unit divided by 384,400 km gives 389.172400364. No numerical contradiction.
- CONFIRMED | The Sun wins the pull and loses the tide, by exactly the margin the third power demands. | https://oceanservice.noaa.gov/education/tutorial_tides/tides02_cause.html | Checker result at f5e5f84f34, retained from N2-codex.md. [015 sun-loses-tide] NOAA gives approximately half the lunar tide; the independently recomputed inverse-cube ratio is 0.459596630052. "Exactly" describes the ratio identity within the stated leading-order model.
- CONFIRMED | The near-side bulge is easy: the Moon pulls the water nearest it hardest, and it heaps up. | https://oceanservice.noaa.gov/education/tutorial_tides/tides03_gravity.html | Checker result at f5e5f84f34, retained from N2-codex.md. [016 near-bulge] NOAA describes stronger near-side attraction and a near-side bulge. Read as equilibrium geometry, as the page later specifies, not a claim that vertical gravity simply lifts the real ocean.
- CONFIRMED | "centrifugal force flings the water off," | https://oceanservice.noaa.gov/education/tutorial_tides/tides03_gravity.html | Checker result at f5e5f84f34, retained from N2-codex.md. [017 popular-centrifugal-quotation] Read as an unnamed popular paraphrase, not a verbatim NOAA quotation. NOAA says "inertia exceeds the gravitational force" and describes water moving away from Earth. The source record incorrectly makes this a kind:quote with a literal quote field. The online checker correctly rejects that encoding.
- CONFIRMED | "the Earth gets pulled out from under the far ocean" | https://fr.wikisource.org/wiki/%C5%92uvres_compl%C3%A8tes_de_Laplace/M%C3%A9moire_sur_le_flux_et_reflux_de_la_mer | Checker result at f5e5f84f34, retained from N2-codex.md. [018 popular-earth-pulled-quotation] Read as an unnamed popular paraphrase. Laplace describes Earth separating from the less-attracted far-side molecule: "la surface du globe terrestre tend donc à s’en séparer". These are not the English words in the record’s quote field; repair that field, not a fabricated attribution on the page.
- CONFIRMED | the tidal force is the gradient of gravity, and a gradient points outward on both ends. | https://geo.libretexts.org/Bookshelves/Oceanography/Introduction_to_Physical_Oceanography_(Stewart)/17%3A_Coastal_Processes_and_Tides/17.4%3A_Theory_of_Ocean_Tides | Checker result at f5e5f84f34, retained from N2-codex.md. [019 gradient-two-ends] Stewart: the gradient produces "a pair of bulges of water on Earth" on the facing and opposite sides, under the stated equilibrium assumptions.
- OBSERVED | Drag the Moon and watch the actual field. | git show f5e5f84f34:public/strata/the-tide-textbook-got-wrong/index.html | Checker result at f5e5f84f34, retained from N2-codex.md. [020 drag-actual-field] Pinned HTML lines 314-326 subtract the centre acceleration vector and rotate it with the Moon; lines 338-395 normalize and draw 24 vectors. At the near/far points the radial components are positive, and at the sides negative. Pointer and keyboard handlers call draw(). This checks the implementation without a browser.
- OBSERVED | arrows show the residual (tide-raising) acceleration, scaled up to be visible | git show f5e5f84f34:public/strata/the-tide-textbook-got-wrong/index.html | Checker result at f5e5f84f34, retained from N2-codex.md. [021 arrows-residual] Pinned HTML lines 314-326 subtract the centre acceleration vector and rotate it with the Moon; lines 338-395 normalize and draw 24 vectors. At the near/far points the radial components are positive, and at the sides negative. Pointer and keyboard handlers call draw(). This checks the implementation without a browser.
- OBSERVED | An exaggerated map of the tidal acceleration across the Earth's surface. Arrows point outward at the points nearest and farthest from the Moon, and inward along the sides, forming two bulges. | git show f5e5f84f34:public/strata/the-tide-textbook-got-wrong/index.html | Checker result at f5e5f84f34, retained from N2-codex.md. [022 canvas-accessible-description] Pinned HTML lines 314-326 subtract the centre acceleration vector and rotate it with the Moon; lines 338-395 normalize and draw 24 vectors. At the near/far points the radial components are positive, and at the sides negative. Pointer and keyboard handlers call draw(). This checks the implementation without a browser.
- CONFIRMED | near-side pull (outward) 1.13×10⁻⁶ m/s² | git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs; research/assay-line/queue-1014c/the-tide-textbook-got-wrong/N2-codex.md | Checker result at f5e5f84f34, retained from N2-codex.md. [023 near-readout] Independent inverse-square subtraction gives near 1.12722373023e-6 m/s², far 1.07254078355e-6 m/s², far/near 0.951488825856. The displayed rounded values and approximately 5% difference are correct. These are accelerations, not measured sea-level heights.
- CONFIRMED | far-side pull (outward) 1.07×10⁻⁶ m/s² | git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs; research/assay-line/queue-1014c/the-tide-textbook-got-wrong/N2-codex.md | Checker result at f5e5f84f34, retained from N2-codex.md. [024 far-readout] Independent inverse-square subtraction gives near 1.12722373023e-6 m/s², far 1.07254078355e-6 m/s², far/near 0.951488825856. The displayed rounded values and approximately 5% difference are correct. These are accelerations, not measured sea-level heights.
- CONFIRMED | far ÷ near 0.951 | git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs; research/assay-line/queue-1014c/the-tide-textbook-got-wrong/N2-codex.md | Checker result at f5e5f84f34, retained from N2-codex.md. [025 ratio-readout] Independent inverse-square subtraction gives near 1.12722373023e-6 m/s², far 1.07254078355e-6 m/s², far/near 0.951488825856. The displayed rounded values and approximately 5% difference are correct. These are accelerations, not measured sea-level heights.
- MINOR | X1: sideways squeeze (inward) ½ of outward | https://geo.libretexts.org/Bookshelves/Oceanography/Introduction_to_Physical_Oceanography_(Stewart)/17%3A_Coastal_Processes_and_Tides/17.4%3A_Theory_of_Ocean_Tides | Stewart §17.4 explicitly truncates higher-order terms. Independent evaluation of the exact page field gives sideways/near = 0.487403369 and sideways/far = 0.512253382. One half is the leading-order comparison.
- CONFIRMED | Subtract the pull on the Earth's centre from the pull at each point of the surface | https://fr.wikisource.org/wiki/%C5%92uvres_compl%C3%A8tes_de_Laplace/M%C3%A9moire_sur_le_flux_et_reflux_de_la_mer | Checker result at f5e5f84f34, retained from N2-codex.md. [027 subtract-centre] Laplace: "la différence de ces forces et par l’inégalité de leurs directions." The surrounding paragraph compares the attraction on a sea molecule with that on Earth’s centre.
- CONFIRMED | At the point nearest the Moon the residual points toward the Moon (outward). | https://fr.wikisource.org/wiki/%C5%92uvres_compl%C3%A8tes_de_Laplace/M%C3%A9moire_sur_le_flux_et_reflux_de_la_mer | Checker result at f5e5f84f34, retained from N2-codex.md. [028 near-residual] Laplace: a molecule under the attracting body "en est plus attirée que le centre de la Terre". The paragraph uses the Sun; the same differential law applies to the Moon.
- CONFIRMED | At the point farthest away, gravity is weaker than at the centre, so relative to the centre the water there is left behind | https://fr.wikisource.org/wiki/%C5%92uvres_compl%C3%A8tes_de_Laplace/M%C3%A9moire_sur_le_flux_et_reflux_de_la_mer | Checker result at f5e5f84f34, retained from N2-codex.md. [029 far-residual] Laplace: on the opposite side the body "l’attire plus faiblement que le centre de la Terre". The comparison supports the outward far-side residual.
- CONFIRMED | "left behind on the far side" means heaped outward, away from the Moon. | https://oceanservice.noaa.gov/education/tutorial_tides/tides03_gravity.html | Checker result at f5e5f84f34, retained from N2-codex.md. [030 left-behind-outward] The selected sentence only states weaker far-side attraction. Reading the next sentence supplies the missing support: water is "moving away from the Earth, also forming a bulge".
- CONFIRMED | Computed exactly from the inverse-square law, the far bulge comes out at 1.07×10⁻⁶ m/s² against the near side's 1.13×10⁻⁶: real, outward, and only about 5% smaller. | git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs; research/assay-line/queue-1014c/the-tide-textbook-got-wrong/N2-codex.md | Checker result at f5e5f84f34, retained from N2-codex.md. [031 far-near-exact] Independent inverse-square subtraction gives near 1.12722373023e-6 m/s², far 1.07254078355e-6 m/s², far/near 0.951488825856. The displayed rounded values and approximately 5% difference are correct. These are accelerations, not measured sea-level heights.
- CONFIRMED | Not centrifugal. | https://www.wtamu.edu/~cbaird/sq/2012/12/14/i-know-that-the-gravity-of-the-moon-causes-ocean-tides-on-earth-how-does-centrifugal-force-cause-the-far-side-bulge/ | Checker result at f5e5f84f34, retained from N2-codex.md. [032 not-centrifugal] Baird explicitly says "not caused by centrifugal force" and explains the gravitational gradient. A nonrotating free-fall description supplies both residuals without a centrifugal explanation.
- WRONG | X2: Just the difference of a force across eight thousand kilometres of rock. | https://nssdc.gsfc.nasa.gov/planetary/factsheet/earthfact.html | NASA gives a volumetric mean radius of 6371.000 km. Twice that is 12,742 km, rounded here to about 12,700 km. The sentence describes the full near-to-far width.
- CONFIRMED | Working in the rotating Earth–Moon frame, you can add a centrifugal term and balance the books | https://fujiwaratko.sakura.ne.jp/tidal/tidal_force_e.html | Checker result at f5e5f84f34, retained from N2-codex.md. [034 rotating-frame] A rotating frame can be used, with its centrifugal and other inertial terms treated consistently. Fujiwara distinguishes this from the uniform translational inertial force. The next clause conflates the frames; see entry 35.
- WRONG | X3: but it's a uniform translation of every point alike, not a spin that "throws" the far ocean outward. | https://fujiwaratko.sakura.ne.jp/tidal/tidal_force_e.html | Fujiwara distinguishes the uniform translational inertial acceleration of an Earth-centred non-rotating frame from centrifugal acceleration proportional to distance from the rotation axis. The original paragraph assigned uniformity to the latter.
- CONFIRMED | The Earth's monthly revolution about the shared barycentre accelerates every grain of the planet equally; what's left over, point to point, is the same gravitational gradient. | https://fujiwaratko.sakura.ne.jp/tidal/tidal_force_e.html | Checker result at f5e5f84f34, retained from N2-codex.md. [036 barycentre-equal] As a statement about the common translational acceleration, this is correct. Fujiwara describes the "translational acceleration of the earth toward the moon". Do not confuse it with the spatial dependence of a rotating coordinate frame, addressed in entry 35.
- CONFIRMED | The far bulge needs no fictitious force. | https://www.wtamu.edu/~cbaird/sq/2012/12/14/i-know-that-the-gravity-of-the-moon-causes-ocean-tides-on-earth-how-does-centrifugal-force-cause-the-far-side-bulge/ | Checker result at f5e5f84f34, retained from N2-codex.md. [037 no-fictitious-force] Baird explicitly says "not caused by centrifugal force" and explains the gravitational gradient. A nonrotating free-fall description supplies both residuals without a centrifugal explanation.
- CONFIRMED | The Sun's tide is 0.46 of the Moon's | https://geo.libretexts.org/Bookshelves/Oceanography/Introduction_to_Physical_Oceanography_(Stewart)/17%3A_Coastal_Processes_and_Tides/17.4%3A_Theory_of_Ocean_Tides | Checker result at f5e5f84f34, retained from N2-codex.md. [038 solar-tide-ratio] Stewart explicitly gives the solar/lunar tide-strength ratio as "0.46051". The page’s constants give 0.45960, consistent with 0.46.
- CONFIRMED | When the two line up (new Moon and full Moon) their bulges add | https://oceanservice.noaa.gov/facts/springtide.html; git show f5e5f84f34:public/strata/the-tide-textbook-got-wrong/index.html | Checker result at f5e5f84f34, retained from N2-codex.md. [039 aligned-add] NOAA describes alignment at new/full Moon and partial cancellation at the quarter phases. The pinned phase table implements those four choices; it prints 0.78 m for alignment and 0.29 m for quadrature.
- CONFIRMED | when they pull at right angles (the quarter Moons) the Sun's bulge sits in the Moon's trough and partly cancels it. | https://oceanservice.noaa.gov/facts/springtide.html; git show f5e5f84f34:public/strata/the-tide-textbook-got-wrong/index.html | Checker result at f5e5f84f34, retained from N2-codex.md. [040 quarters-cancel] NOAA describes alignment at new/full Moon and partial cancellation at the quarter phases. The pinned phase table implements those four choices; it prints 0.78 m for alignment and 0.29 m for quadrature.
- MINOR | X4: That is the two-week swing every tide table shows: the big spring tides and the meek neap ones. | https://tidesandcurrents.noaa.gov/glossary.html | NOAA limits the useful spring-range comparison to semidiurnal or mixed tides and says it has no practical significance for predominantly diurnal tides. The universal tide-table claim was too broad.
- CONFIRMED | combined high–low range 0.78 m | git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs; research/assay-line/queue-1014c/the-tide-textbook-got-wrong/N2-codex.md | Checker result at f5e5f84f34, retained from N2-codex.md. [042 combined-range] Independent evaluation gives lunar height 0.356584533312 m, solar height 0.163885049839 m, spring range 0.780704374725 m, and equatorial neap range 0.289049225210 m. The phase panel agrees. These are the ideal spherical-ocean, aligned/equatorial values.
- CONFIRMED | combined high–low range 0.29 m | git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs; research/assay-line/queue-1014c/the-tide-textbook-got-wrong/N2-codex.md | Checker result at f5e5f84f34, retained from N2-codex.md. [043 neap-range-built] Independent evaluation gives lunar height 0.356584533312 m, solar height 0.163885049839 m, spring range 0.780704374725 m, and equatorial neap range 0.289049225210 m. The phase panel agrees. These are the ideal spherical-ocean, aligned/equatorial values.
- CONFIRMED | aligned [...] bulges add (spring) | https://oceanservice.noaa.gov/facts/springtide.html; git show f5e5f84f34:public/strata/the-tide-textbook-got-wrong/index.html | Checker result at f5e5f84f34, retained from N2-codex.md. [044 new-phase] NOAA describes alignment at new/full Moon and partial cancellation at the quarter phases. The pinned phase table implements those four choices; it prints 0.78 m for alignment and 0.29 m for quadrature.
- CONFIRMED | aligned, opposite sides [...] bulges still add (spring) | https://oceanservice.noaa.gov/facts/springtide.html; git show f5e5f84f34:public/strata/the-tide-textbook-got-wrong/index.html | Checker result at f5e5f84f34, retained from N2-codex.md. [045 full-phase] NOAA describes alignment at new/full Moon and partial cancellation at the quarter phases. The pinned phase table implements those four choices; it prints 0.78 m for alignment and 0.29 m for quadrature.
- CONFIRMED | at right angles [...] Sun fills the Moon's trough (neap) | https://oceanservice.noaa.gov/facts/springtide.html; git show f5e5f84f34:public/strata/the-tide-textbook-got-wrong/index.html | Checker result at f5e5f84f34, retained from N2-codex.md. [046 quarter-phase] NOAA describes alignment at new/full Moon and partial cancellation at the quarter phases. The pinned phase table implements those four choices; it prints 0.78 m for alignment and 0.29 m for quadrature.
- CONFIRMED | at right angles [...] partial cancellation (neap) | https://oceanservice.noaa.gov/facts/springtide.html; git show f5e5f84f34:public/strata/the-tide-textbook-got-wrong/index.html | Checker result at f5e5f84f34, retained from N2-codex.md. [047 third-phase] NOAA describes alignment at new/full Moon and partial cancellation at the quarter phases. The pinned phase table implements those four choices; it prints 0.78 m for alignment and 0.29 m for quadrature.
- CONFIRMED | Spring tides aren't seasonal | https://oceanservice.noaa.gov/facts/springtide.html | Checker result at f5e5f84f34, retained from N2-codex.md. [048 spring-not-seasonal] NOAA: "Spring tides occur twice each lunar month all year long without regard to the season." "Every fortnight" is the conventional approximate period, not exactly 14 days.
- CONFIRMED | "spring" is from the old sense of welling up. | https://www.glf.dfo-mpo.gc.ca/en/frequently-asked-questions | Checker result at f5e5f84f34, retained from N2-codex.md. [049 spring-etymology] Opened with curl after UNREADABLE. Fisheries and Oceans Canada: "springan" "means to well up". The exact excerpt is present.
- CONFIRMED | They follow the Moon's phase, every fortnight, year-round. | https://oceanservice.noaa.gov/facts/springtide.html | Checker result at f5e5f84f34, retained from N2-codex.md. [050 fortnight-year-round] NOAA: "Spring tides occur twice each lunar month all year long without regard to the season." "Every fortnight" is the conventional approximate period, not exactly 14 days.
- UNVERIFIABLE | Now the honest part, the one most pages skip. | https://oceanservice.noaa.gov/education/tutorial_tides/tides07_cycles.html; https://www.krm.or.kr/krmts/link.html?dbGubun=SD&local_id=10083218&m201_id=10062232 | Checker result at f5e5f84f34, retained from N2-codex.md. [051 most-pages-skip] No defined population or measured majority is supplied. Search: "equilibrium tide" "most" "textbooks". Positive controls found an actual study of textbook tide models and NOAA’s discussion of continental interference. These establish examples, not a majority of pages.
- CONFIRMED | Everything above is equilibrium theory | git show f5e5f84f34:public/strata/the-tide-textbook-got-wrong/index.html | Checker result at f5e5f84f34, retained from N2-codex.md. [052 everything-equilibrium] The preceding sections compute a static gravitational residual and equilibrium heights/ranges; they do not solve ocean dynamics. This correctly describes their scope.
- CONFIRMED | Newton's idealization, in which the ocean has time to settle into the static egg the Moon's gravity wants. | https://fr.wikisource.org/wiki/%C5%92uvres_compl%C3%A8tes_de_Laplace/M%C3%A9moire_sur_le_flux_et_reflux_de_la_mer | Checker result at f5e5f84f34, retained from N2-codex.md. [053 newton-idealization] Laplace’s historical account: Newton "supposa la mer en équilibre à chaque instant". This supports the equilibrium idealization, but not entry 105’s denial that Newton applied it to the real ocean.
- CONFIRMED | The equilibrium high tide comes to about 0.36 m for the Moon and 0.16 m for the Sun | git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs; research/assay-line/queue-1014c/the-tide-textbook-got-wrong/N2-codex.md | Checker result at f5e5f84f34, retained from N2-codex.md. [054 equilibrium-highs] Independent evaluation gives lunar height 0.356584533312 m, solar height 0.163885049839 m, spring range 0.780704374725 m, and equatorial neap range 0.289049225210 m. The phase panel agrees. These are the ideal spherical-ocean, aligned/equatorial values.
- CONFIRMED | a combined spring range, high to low, of about 0.78 m. | git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs; research/assay-line/queue-1014c/the-tide-textbook-got-wrong/N2-codex.md | Checker result at f5e5f84f34, retained from N2-codex.md. [055 spring-range-078] Independent evaluation gives lunar height 0.356584533312 m, solar height 0.163885049839 m, spring range 0.780704374725 m, and equatorial neap range 0.289049225210 m. The phase panel agrees. These are the ideal spherical-ocean, aligned/equatorial values.
- CONFIRMED | The Bay of Fundy gets sixteen metres. | https://www.glf.dfo-mpo.gc.ca/en/frequently-asked-questions | Checker result at f5e5f84f34, retained from N2-codex.md. [056 fundy-sixteen] Opened with curl after UNREADABLE. Fisheries and Oceans Canada explicitly gives a "16 metre (53 foot) tide range" for Minas Basin and Leaf Basin.
- CONFIRMED | The equilibrium bulge is off by more than a factor of twenty | git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs; https://www.glf.dfo-mpo.gc.ca/en/frequently-asked-questions | Checker result at f5e5f84f34, retained from N2-codex.md. [057 twentyfold] 16 / 0.780704374725 = 20.4943132356, greater than twenty. The verifier’s integer output rounds to 20; that rounding does not refute the inequality.
- CONFIRMED | no refinement of Newton's static ocean will ever close that gap, because the static ocean is the wrong model. | https://fr.wikisource.org/wiki/%C5%92uvres_compl%C3%A8tes_de_Laplace/M%C3%A9moire_sur_le_flux_et_reflux_de_la_mer | Checker result at f5e5f84f34, retained from N2-codex.md. [058 no-refinement] Laplace says Earth’s rapid rotation prevents the waters taking the instantaneous equilibrium figure. Read in context as the global short-period lunar bulge, not a denial of all long-period or locally near-equilibrium responses.
- CONFIRMED | A tide is a wave | https://oceanservice.noaa.gov/facts/springtide.html | Checker result at f5e5f84f34, retained from N2-codex.md. [059 tide-wave] NOAA calls tides "long-period waves". This supports treating real tides dynamically.
- CONFIRMED | a wave in water of depth H can move no faster than √(gH). | https://geo.libretexts.org/Bookshelves/Oceanography/Introduction_to_Physical_Oceanography_(Stewart)/16%3A_Ocean_Waves/16.1%3A_Linear_Theory_of_Ocean_Surface_Waves | Checker result at f5e5f84f34, retained from N2-codex.md. [060 wave-speed-bound] For the linear surface gravity waves at issue, Stewart gives omega² = g k tanh(kd); tanh(kd) <= kd implies phase speed <= sqrt(gd). This is not a bound on acoustic waves or all forced phase patterns.
- CONFIRMED | With the ocean's mean depth of ~3.7 km that ceiling is about 190 m/s. | https://oceanservice.noaa.gov/facts/oceandepth.html; git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs | Checker result at f5e5f84f34, retained from N2-codex.md. [061 ocean-depth] NOAA’s depth is "3,682 meters"; rounding to 3.7 km and computing sqrt(9.80665 * 3700) gives 190.485183151 m/s.
- WRONG | X5: But the point beneath the Moon races west around the equator at 465 m/s | https://geo.libretexts.org/Bookshelves/Oceanography/Introduction_to_Physical_Oceanography_(Stewart)/17%3A_Coastal_Processes_and_Tides/17.4%3A_Theory_of_Ocean_Tides; git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs | Stewart §17.4, Tidal Frequencies, gives a mean lunar day of 24 h 50.47 min = 89428.2 s. With the page radius, 2*pi*6371000/89428.2 = 447.623608571 m/s. The original verifier used the sidereal day and returned 464.580701 m/s.
- WRONG | X6: how fast the Moon's bulge-point sweeps the equator 465 m/s | https://geo.libretexts.org/Bookshelves/Oceanography/Introduction_to_Physical_Oceanography_(Stewart)/17%3A_Coastal_Processes_and_Tides/17.4%3A_Theory_of_Ocean_Tides; git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs | The panel repeated the sidereal-period error. The source lunar period and page radius give a mean equatorial forcing speed of 447.623608571 m/s, rounded to 448 m/s.
- CONFIRMED | how fast a tidal wave can actually travel (√gH, mean ocean) 190 m/s | https://oceanservice.noaa.gov/facts/oceandepth.html; git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs | Checker result at f5e5f84f34, retained from N2-codex.md. [064 wave-speed-190] NOAA’s depth is "3,682 meters"; rounding to 3.7 km and computing sqrt(9.80665 * 3700) gives 190.485183151 m/s.
- CONFIRMED | more than twice the speed the water could ever chase it at. | git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs; research/assay-line/queue-1014c/the-tide-textbook-got-wrong/N2-codex.md | Checker result at f5e5f84f34, retained from N2-codex.md. [065 twice-wave-speed] Even with the corrected mean equatorial speed, 447.623609 / 190.485183 = 2.349913, so the greater-than-two comparison survives. It concerns wave propagation, not a requirement that individual water parcels travel at that speed.
- CONFIRMED | So the real ocean never reaches equilibrium. | https://fr.wikisource.org/wiki/%C5%92uvres_compl%C3%A8tes_de_Laplace/M%C3%A9moire_sur_le_flux_et_reflux_de_la_mer | Checker result at f5e5f84f34, retained from N2-codex.md. [066 never-equilibrium] Laplace says Earth’s rapid rotation prevents the waters taking the instantaneous equilibrium figure. Read in context as the global short-period lunar bulge, not a denial of all long-period or locally near-equilibrium responses.
- CONFIRMED | Instead the tide behaves as a forced wave sloshing in the basins, the way water in a carried bowl heaps at the walls | https://geo.libretexts.org/Bookshelves/Oceanography/Introduction_to_Physical_Oceanography_(Stewart)/17%3A_Coastal_Processes_and_Tides/17.4%3A_Theory_of_Ocean_Tides | Checker result at f5e5f84f34, retained from N2-codex.md. [067 forced-wave] Stewart describes "near-resonant, sloshing of water in a rotating, elastic ocean basin". The bowl comparison is an analogy, not an exact basin solution.
- CONFIRMED | Laplace's dynamic theory (Paris Académie, 1775–76) | https://fr.wikisource.org/wiki/%C5%92uvres_compl%C3%A8tes_de_Laplace/M%C3%A9moire_sur_le_flux_et_reflux_de_la_mer | Checker result at f5e5f84f34, retained from N2-codex.md. [068 laplace-dates] Laplace explicitly identifies his "Mémoires pour les années 1775 et 1776". These are the memoir years stated on the page.
- CONFIRMED | the equations we still solve. | https://geo.libretexts.org/Bookshelves/Oceanography/Introduction_to_Physical_Oceanography_(Stewart)/17%3A_Coastal_Processes_and_Tides/17.4%3A_Theory_of_Ocean_Tides | Checker result at f5e5f84f34, retained from N2-codex.md. [069 equations-still-solved] Stewart: "Tides are calculated from the hydrodynamic equations for a self-gravitating ocean on a rotating, elastic Earth." Modern tidal calculations develop this dynamical framework; the page does not claim to compute the map itself.
- CONFIRMED | In a basin the tide runs around the edges as a rotary wave, pivoting about still points called amphidromic points where the range falls to nearly zero. | https://tidesandcurrents.noaa.gov/glossary.html | Checker result at f5e5f84f34, retained from N2-codex.md. [070 amphidromes] NOAA defines an amphidromic point as "A point of zero amplitude of the observed or a constituent tide" and describes radiating cotidal lines through all hours. The nearly-zero wording is appropriate.
- CONFIRMED | William Whewell predicted such a no-tide point in the North Sea in 1836 | https://archive.org/download/jstor-108036/108036_djvu.txt | Checker result at f5e5f84f34, retained from N2-codex.md. [071 whewell-1836] Read the 1836 paper’s text: "a tideless centre, as D, about which the cotidal lines revolve." The document is Researches on the Tides, Sixth Series, in the 1836 volume.
- CONFIRMED | the surveyor William Hewett sailed out and confirmed it in 1840. | https://philsci-archive.pitt.edu/4847/1/WHEWELL_TIDES_SHPS_-_REVISED_VERSION_13_August_2009.pdf | Checker result at f5e5f84f34, retained from N2-codex.md. [072 hewett-1840] Opened the actual PDF with curl and pdftotext after UNREADABLE. Footnote 63, manuscript p. 94, says Hewett "confirmed Whewell’s predicted point of no tide in 1840" and cites Reidy 2008, pp. 186-187. This is scholarly secondary evidence, not Hewett’s original report.
- MINOR | X7: There are roughly a dozen major amphidromic systems for the principal lunar tide, give or take how you count them | https://nora.nerc.ac.uk/id/eprint/117319/1/Revision_GRSL-00042-2005.pdf | Chen and Quartly, Introduction, PDF p. 2, discuss diurnal and semidiurnal amphidromes together. Their approximate count does not establish an M2-only census. This is a citation-scope mismatch, not proof that a specified M2 count is false.
- MINOR | X8: around each one, high tide arrives at a different hour at every port on the shore. | https://tidesandcurrents.noaa.gov/glossary.html | NOAA defines cotidal lines as connecting places with the same tidal hour. Spatially varying phase does not require a different hour at every port.
- CONFIRMED | X9: at most places, high tide does not happen when the Moon is overhead. | https://oceanservice.noaa.gov/facts/moon-tide.html; https://tidesandcurrents.noaa.gov/glossary.html; https://fujiwaratko.sakura.ne.jp/tidal/tidal_force_e.html | REJECTED with evidence: NOAA moon-tide.html directly explains that local high water generally does not coincide with lunar transit and that geographic delays can last hours. In context this is the qualitative failure of the Moon-aligned picture. A weak selected glossary excerpt supplies no contrary timing evidence and does not justify weakening the generalization.
- MINOR | X10: sailors called it the establishment of the port | https://tidesandcurrents.noaa.gov/glossary.html | NOAA defines the common establishment as an average high-water interval on new- and full-Moon days, distinguishing the corrected all-phase average. Individual high-water intervals can vary.
- CONFIRMED | X11: is a fixed local number you can read off a chart | https://tidesandcurrents.noaa.gov/glossary.html | REJECTED with evidence: NOAA defines establishment as an average, so the original chart value can be a fixed tabulated statistic without asserting identical delays for individual tides. The complete sentence names that statistic. X10 supplies its missing definition as a MINOR clarification; this alleged WRONG is not retained as WRONG.
- CONFIRMED | it has nothing to do with a bulge sitting under the Moon, because there is no such bulge. | https://ntslf.org/tides/about-tides/tides-faq | Checker result at f5e5f84f34, retained from N2-codex.md. [078 no-real-bulge] The National Tidal and Sea Level Facility explicitly says "such a bulge does not exist in nature" about the global ovoid aligned with the Moon. This supplies stronger support than the record’s continental-interference excerpt.
- MINOR | X12: The Moon sets the rhythm; the shape of the sea floor sets everything else. | https://fr.wikisource.org/wiki/%C5%92uvres_compl%C3%A8tes_de_Laplace/M%C3%A9moire_sur_le_flux_et_reflux_de_la_mer; https://geo.libretexts.org/Bookshelves/Oceanography/Introduction_to_Physical_Oceanography_(Stewart)/17%3A_Coastal_Processes_and_Tides/17.4%3A_Theory_of_Ocean_Tides | Laplace discusses resistance and local intervals, while Stewart describes rotating, elastic basins forced by both Moon and Sun. Seafloor shape alone does not determine every part of the local response.
- MINOR | X13: the cadence right (twice a day, springs every fortnight) | https://oceanservice.noaa.gov/education/tutorial_tides/tides07_cycles.html | NOAA distinguishes semidiurnal, mixed and diurnal regimes, with Gulf of Mexico examples of one high and one low per lunar day. Two highs per lunar day describes the semidiurnal case.
- MINOR | X14: nothing at all into a patch of the North Sea | https://tidesandcurrents.noaa.gov/glossary.html | NOAA defines an amphidromic zero at a point for an observed tide or one constituent. It does not imply zero total water-level change over an extended patch.
- WRONG | X15: all of it forced by a difference in gravity so small you'd need a hundred-thousandth of Earth's own pull to measure it. | git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs; git show f5e5f84f34:public/strata/the-tide-textbook-got-wrong/index.html:410 | Independent inverse-square subtraction with the pinned inputs gives a near-side lunar residual of 1.127223730225e-6 m/s²; dividing by 9.80665 gives 1.149448313364e-7. With the NASA mass alignment in X19 it is 1.150074545079e-7. Both are about a ten-millionth, consistent with the canvas annotation.
- CONFIRMED | the real gradient is ~10⁻⁷ of surface gravity | git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs; research/assay-line/queue-1014c/the-tide-textbook-got-wrong/N2-codex.md | Checker result at f5e5f84f34, retained from N2-codex.md. [083 canvas-gradient-scale] The independently computed near-side tidal acceleration divided by standard gravity is 1.14944831336e-7. This is the correct order of magnitude; entry 82 contradicts it.
- OBSERVED | distance & arrows exaggerated | git show f5e5f84f34:public/strata/the-tide-textbook-got-wrong/index.html | Checker result at f5e5f84f34, retained from N2-codex.md. [084 canvas-exaggeration] Pinned HTML sets display Earth radius to 66 pixels and Moon distance to 150 pixels, while physical R/D is 6.371e6 / 3.844e8. Arrows are normalized to a 34-pixel maximum. The annotation accurately discloses the exaggeration.
- CONFIRMED | RECOMPUTED FROM PRIMARY CONSTANTS | git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs | Checker result at f5e5f84f34, retained from N2-codex.md. [085 header-primary-constants] The numerical model recomputes its principal results from declared G, masses, radii, distances, rotation period and depth. The lunar period interpretation and two exact mass attributions need separate repairs, recorded below.
- OBSERVED | 21/21 CHECKS GREEN | git show f5e5f84f34:research/self-check/verifier-runs.json | Checker result at f5e5f84f34, retained from N2-codex.md. [086 header-checks] Committed run records "pass": 21, "fail": 0, "total": 21 at 2026-08-01T13:02:09.145Z. Recreated from the live downloadable file: exit 0, "21/21 checks passed." Incorrect physics in one assertion does not falsify the observed program result.
- MINOR | X16: res/the-tide-textbook-got-wrong/verify.mjs | git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs | The pinned tree and working file contain research/the-tide-textbook-got-wrong/verify.mjs. The header res/ path does not name that file; the body and download link already use research/.
- MINOR | X17: Every figure on this page is recomputed from published constants | git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs | The verifier explicitly excludes gravity laws, amphidromic positions and the observed Fundy record from its proof, and inserts FUNDY_SPRING_RANGE = 16.0 as an observed input. It recomputes principal physical quantities, not every date or observed number.
- OBSERVED | by a standalone script. | git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs | Checker result at f5e5f84f34, retained from N2-codex.md. [089 standalone-script] Downloaded only the linked verify.mjs into an empty reader directory. "node research/the-tide-textbook-got-wrong/verify.mjs" exited 0 with 21 passes and zero failures, without npm or other files.
- OBSERVED | 21/21 checks passed | git show f5e5f84f34:research/self-check/verifier-runs.json | Checker result at f5e5f84f34, retained from N2-codex.md. [090 check-run-result] Committed run records "pass": 21, "fail": 0, "total": 21 at 2026-08-01T13:02:09.145Z. Recreated from the live downloadable file: exit 0, "21/21 checks passed." Incorrect physics in one assertion does not falsify the observed program result.
- OBSERVED | It derives the 179× pull ratio and the 0.46 tide ratio independently and proves they satisfy the identity tide = pull ÷ distance | git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs | Checker result at f5e5f84f34, retained from N2-codex.md. [091 independent-ratios] The program separately computes M/d² and M/d³ and checks "tideRatio = pullRatio / distRatio" at tolerance 1e-9. The independent Python arithmetic agrees.
- OBSERVED | computes the near- and far-side tidal accelerations from the exact differential of GM/r² (not the textbook approximation) and shows both point outward | git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs | Checker result at f5e5f84f34, retained from N2-codex.md. [092 exact-computation] Read function bulges(): it subtracts GM/d² from GM/(d-R)² and GM/(d+R)² from GM/d². Recreated positive residuals on both ends; it also separately computes the approximation for comparison.
- OBSERVED | gets the equilibrium bulge heights and the spring/neap ranges | git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs | Checker result at f5e5f84f34, retained from N2-codex.md. [093 computed-ranges] Read equilHigh() and the 1.5*(hMoon +/- hSun) formulas. Recreated output "rangeSpring": 0.78 and "rangeNeap": 0.29. These are the idealized values stated on the panel.
- WRONG | X18: confirms the forcing point (465 m/s) outruns the shallow-water wave (190 m/s), so no equilibrium bulge can form. | https://geo.libretexts.org/Bookshelves/Oceanography/Introduction_to_Physical_Oceanography_(Stewart)/17%3A_Coastal_Processes_and_Tides/17.4%3A_Theory_of_Ocean_Tides; git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs | The correct mean equatorial speed is 447.623608571 m/s and sqrt(9.80665*3700) = 190.485183151 m/s. Their ratio is 2.349913002. That scalar comparison is a result for the stated mean-depth model, not a solution for tides in real basins. Repair evidence: MIT course notes, sections 3.4.4-3.4.7, distinguish forced-wave speeds from free-wave speeds and then address basin response: https://ocw.mit.edu/courses/12-090-the-environment-of-the-earths-surface-spring-2007/1e6c61fd02d7aacdfd55545e609f0eb5_earthsurface_8.pdf#page=18
- OBSERVED | is the law of gravity itself, the global map of amphidromic points | git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs | Checker result at f5e5f84f34, retained from N2-codex.md. [095 not-derived] The source record excerpt drops the sentence’s negative context. Read in full, the page says these are not proved. The verifier’s "WHAT IT DOES NOT PROVE" comment explicitly names the laws and amphidromic positions, correctly describing its scope.
- CONFIRMED | those come from solving Laplace's equations on the real basins, named here, not re-derived | https://geo.libretexts.org/Bookshelves/Oceanography/Introduction_to_Physical_Oceanography_(Stewart)/17%3A_Coastal_Processes_and_Tides/17.4%3A_Theory_of_Ocean_Tides | Checker result at f5e5f84f34, retained from N2-codex.md. [096 amphidromic-map-equations] Stewart: "Tides are calculated from the hydrodynamic equations for a self-gravitating ocean on a rotating, elastic Earth." Modern tidal calculations develop this dynamical framework; the page does not claim to compute the map itself.
- CONFIRMED | the Bay of Fundy record (a cited observation). | git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs; https://www.glf.dfo-mpo.gc.ca/en/frequently-asked-questions | Checker result at f5e5f84f34, retained from N2-codex.md. [097 fundy-not-derived] The code labels "OBSERVED (cited, not derived)" and uses a fixed 16.0 m input. Fisheries and Oceans Canada independently confirms the approximate 16 m range.
- CONFIRMED | Constants: CODATA 2018 (G) | https://physics.nist.gov/cuu/pdf/wall_2018.pdf | Checker result at f5e5f84f34, retained from N2-codex.md. [098 citation-codata] Opened the PDF after UNREADABLE. NIST’s 2018 table row reads "6.674 30(15) × 10−11" for G; the verifier uses 6.67430e-11.
- CONFIRMED | IAU 2015 / NASA fact sheets (masses, radii, distances) | https://iau-a3.gitlab.io/res.html | Checker result at f5e5f84f34, retained from N2-codex.md. [099 citation-iau-nasa] The IAU page actually lists 2015 Resolution B3 and its "nominal conversion constants". It recommends solar mass parameters, not the exact kilogram values used here. The resolution citation exists; the two NASA mass mismatches are separate entries.
- CONFIRMED | IAU 2015 / NASA fact sheets (masses, radii, distances) | https://nssdc.gsfc.nasa.gov/planetary/factsheet/earthfact.html | Checker result at f5e5f84f34, retained from N2-codex.md. [100 citation-nasa-earth] NASA gives Earth mass 5.9722e24 kg, mean radius 6371.000 km and semimajor axis 149.598 million km. The verifier’s 5.97217e24 rounds to the cited mass, and the geometric values match their quoted precision.
- MINOR | X19: IAU 2015 / NASA fact sheets (masses, radii, distances) | https://nssdc.gsfc.nasa.gov/planetary/factsheet/moonfact.html | NASA Moon Fact Sheet, updated 11 January 2024, gives 0.07346 in units of 10^24 kg, or 7.346e22 kg. The original 7.342e22 kg does not match that cited value. Recalculation with this and X20 gives pull ratio 178.718192864 and tide ratio 0.459226278; headline 179 and 0.46 survive.
- MINOR | X20: IAU 2015 / NASA fact sheets (masses, radii, distances) | https://nssdc.gsfc.nasa.gov/planetary/factsheet/sunfact.html | NASA Sun Fact Sheet, updated 9 May 2024, gives 1,988,400 in units of 10^24 kg, or 1.9884e30 kg. The original 1.98892e30 kg does not match it. With X19, displayed precision changes to 178.7 and canonical tideRatio 0.459; rounded equilibrium ranges remain 0.78 m and 0.29 m.
- CONFIRMED | IAU 2012 (the astronomical unit). | https://iau-a3.gitlab.io/res.html | Checker result at f5e5f84f34, retained from N2-codex.md. [103 citation-au] IAU 2012 Resolution B2: "149 597 870 700 m exactly". This exactly matches a_sun = 1.495978707e11.
- CONFIRMED | Equilibrium theory: Newton, Principia (1687) | https://oceanservice.noaa.gov/education/tutorial_tides/tides02_cause.html | Checker result at f5e5f84f34, retained from N2-codex.md. [104 citation-newton] NOAA dates Newton’s gravitational tide account to 1687; the Principia text supplies the equilibrium account. The title/year are sound.
- WRONG | X21: the static two-bulge idealization, an assumption about an imaginary instantaneously-adjusting ocean, never a claim about the real one. | https://www.gutenberg.org/files/76404/76404-src/76404-src.htm | Newton, Principia, Book III, Proposition XXIV, printed pp. 415-416 of the 1846 English edition, explicitly invokes experience and applies the model to observed flood timing. The denial of any real-ocean application is false.
- CONFIRMED | Dynamic theory: Laplace, memoirs to the Paris Académie des Sciences (1775–76) | https://fr.wikisource.org/wiki/%C5%92uvres_compl%C3%A8tes_de_Laplace/M%C3%A9moire_sur_le_flux_et_reflux_de_la_mer | Checker result at f5e5f84f34, retained from N2-codex.md. [106 citation-laplace] Laplace explicitly identifies his "Mémoires pour les années 1775 et 1776". These are the memoir years stated on the page.
- CONFIRMED | Amphidromic points: Whewell's predicted North Sea no-tide point (1836), confirmed by Hewett (1840). | https://philsci-archive.pitt.edu/4847/1/WHEWELL_TIDES_SHPS_-_REVISED_VERSION_13_August_2009.pdf | Checker result at f5e5f84f34, retained from N2-codex.md. [107 citation-whewell-hewett] Opened the actual PDF with curl and pdftotext after UNREADABLE. Footnote 63, manuscript p. 94, says Hewett "confirmed Whewell’s predicted point of no tide in 1840" and cites Reidy 2008, pp. 186-187. This is scholarly secondary evidence, not Hewett’s original report.
- MINOR | X22: The count of "roughly a dozen" major M2 systems varies by counting convention. | https://nora.nerc.ac.uk/id/eprint/117319/1/Revision_GRSL-00042-2005.pdf | The full Chen-Quartly introduction, PDF p. 2, covers diurnal and semidiurnal amphidromes. It does not identify a global M2 counting convention. Omission avoids inventing a replacement count.
- MINOR | X23: Highest tides: Bay of Fundy great spring range ~16 m (max ~16.3 m, Burntcoat Head; NOAA). | https://oceanservice.noaa.gov/facts/highesttide.html; https://waves-vagues.dfo-mpo.gc.ca/library-bibliotheque/330668.pdf | NOAA supports the Burntcoat Head location but supplies no 16.3 m maximum. The DFO Ecosystem Overview Report for the Minas Basin, Nova Scotia, 2007-05, printed p. 5 (PDF p. 25), gives 16.3 m and cites Dawson (1917). This documents the historical figure without establishing a current certified maximum.
- MINOR | X24: max ~16.3 m, Burntcoat Head; NOAA | https://www.makivvik.ca/article/tidal-truths/; https://waves-vagues.dfo-mpo.gc.ca/library-bibliotheque/330668.pdf | Makivvik gives 16.42 m as its Canadian Hydrographic Service comparison for Burntcoat Head. It does not attribute 16.3 m to NOAA. DFO independently supports the historical 16.3 m figure, which is retained with its actual attribution.
- CONFIRMED | The title is genuinely contested | https://www.makivvik.ca/leaf-bay-tide-research-project-proves-once-again-worlds-highest-tide/ | Checker result at f5e5f84f34, retained from N2-codex.md. [111 contested-record] Makivvik claims the world record for Leaf Basin while NOAA still identifies Fundy. Those two primary organizations substantiate that the title is contested.
- WRONG | X25: a 2024–25 Makivvik survey of Leaf Basin in Ungava Bay reported a comparable ~16.4 m range | https://www.makivvik.ca/article/tidal-truths/ | Makivvik Tidal Truths, Winter 2026, reports 16.81 m for the 2024-25 Leaf Basin survey; its 16.42 m figure refers separately to Burntcoat Head. The feature describes CHS review as pending. It predates the layer, so this is WRONG, not STALE. No claim of present certification is inferred.
- CONFIRMED | not yet certified. | https://www.makivvik.ca/leaf-bay-tide-research-project-proves-once-again-worlds-highest-tide/; https://www.makivvik.ca/article/tidal-truths/ | Checker result at f5e5f84f34, retained from N2-codex.md. [113 not-certified] The 8 September 2025 release says the data were sent to CHS "for review". The Winter 2026 feature also says they will check accuracy before confirming the record. This supports the dated pending status; it does not independently certify the measurement.
- CONFIRMED | The far bulge is the gravitational gradient, not centrifugal "flinging" (NOAA Ocean Service tides tutorial; Baird, West Texas A&M "Science Questions"). | https://www.wtamu.edu/~cbaird/sq/2012/12/14/i-know-that-the-gravity-of-the-moon-causes-ocean-tides-on-earth-how-does-centrifugal-force-cause-the-far-side-bulge/ | Checker result at f5e5f84f34, retained from N2-codex.md. [114 citation-noaa-baird] Baird explicitly supports the gravitational-gradient account and rejects centrifugal causation. NOAA uses an inertia description, which must not be silently represented as Baird’s wording. Neither source supports entry 35’s frame conflation.
- CONFIRMED | NOAA Ocean Service; Baird, WTAMU. | https://oceanservice.noaa.gov/education/tutorial_tides/tides03_gravity.html | Checker result at f5e5f84f34, retained from N2-codex.md. [115 citation-noaa-inertia] The two named sources exist and address the far bulge. NOAA’s "inertia dominates" is its own pedagogical explanation; Baird supplies the explicit rejection of centrifugal causation. These are related accounts, not identical quotations.
- OBSERVED | Every claim checked; every check shown. | git show f5e5f84f34:memory/log.d/2026-06-19T2340Z-tide-textbook-got-wrong.md | Checker result at f5e5f84f34, retained from N2-codex.md. [116 every-claim-checked] The author log records "Verifier first, page second" and "One adversarial fact-check subagent" on history, Fundy and centrifugal claims. This supports a checking event even though this pass finds mistakes. The source record’s verifier alone did not document that external check.
- CONFIRMED | If a number here is wrong, the verifier is the place to prove it. | git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs | Checker result at f5e5f84f34, retained from N2-codex.md. [117 verifier-wrong-number] The accessible verifier exposes the calculations and constants, so a reader can use it to locate errors. It does not automatically test the HTML; the page’s later placard explicitly discloses that limitation.
- OBSERVED | This layer's check works the answer out again from scratch, independently of this page. | git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs | Checker result at f5e5f84f34, retained from N2-codex.md. [118 placard-independent] Read the entire self-contained verifier: it computes from literals and imports no page or data files. The reader run succeeds without a page. This is independence from the page, not an independent astronomical model.
- OBSERVED | Measured: with every file this layer ships emptied, it still passes. | git show f5e5f84f34:research/verifier-independence/depends-1.json | Checker result at f5e5f84f34, retained from N2-codex.md. [119 placard-emptied] The committed slug row records "exitCode": 0, "depends": false, "timedOut": false. The reader recreation also runs without any shipped page files. The original observation is supported.
- OBSERVED | It can settle the finding; it cannot notice a figure that drifted on this page. | git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs | Checker result at f5e5f84f34, retained from N2-codex.md. [120 placard-scope] The code has no HTML input, so changing page text cannot affect its result. The placard accurately states this limitation. Claims-pass step 6 is conditional on reading the page and therefore does not apply here.
- OBSERVED | It is published, and it runs on its own: one file, and Node. | git show f5e5f84f34:research/source-mirror/results/shard-0.jsonl | Checker result at f5e5f84f34, retained from N2-codex.md. [121 placard-published] The committed source-mirror row says "verdict": "runs", "refExit": 0 and "own" containing only this verifier. The live URL returns HTTP 200, 12,284 bytes; its SHA-256 exactly matches the pinned verifier. Empty-directory run succeeds.
- OBSERVED | Last verified 19 June 2026, when it was written. | git show f5e5f84f34:memory/log.d/2026-06-19T2340Z-tide-textbook-got-wrong.md | Checker result at f5e5f84f34, retained from N2-codex.md. [122 last-verified] The June 19 author log records the checking event. The later August program run is a calculation rerun, not evidence of a later outside-source claims pass. Do not call the original source-check date false because the code was rerun.
- MINOR | X26: Every number on the page is recomputed from published constants by a standalone verifier | git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs | The standalone verifier calculates selected physical quantities and explicitly treats the Fundy range as observed. It does not derive every number on the page. This duplicates X17 in the markdown body and dek.
- WRONG | X27: the proof that the sub-lunar point (465 m/s) outruns a shallow-water wave (190 m/s) so no equilibrium bulge can ever form. | https://geo.libretexts.org/Bookshelves/Oceanography/Introduction_to_Physical_Oceanography_(Stewart)/17%3A_Coastal_Processes_and_Tides/17.4%3A_Theory_of_Ocean_Tides; git show f5e5f84f34:research/the-tide-textbook-got-wrong/verify.mjs | The markdown repeated both the 465 m/s value and the universal-proof wording. Stewart gives the lunar period; independent arithmetic gives 447.623608571 m/s versus a free-wave model speed of 190.485183151 m/s. This is the same error as X5, X6 and X18.
- CONFIRMED | X28: a high tide that almost never arrives when the Moon is overhead. | https://oceanservice.noaa.gov/facts/moon-tide.html; https://tidesandcurrents.noaa.gov/glossary.html; https://fujiwaratko.sakura.ne.jp/tidal/tidal_force_e.html | REJECTED with evidence: NOAA moon-tide.html directly supports the general failure of lunar transit to fix local high-water time. The full markdown sentence summarizes that physical point rather than reporting a census. The glossary excerpt alone is weak, but the checker provides no contrary timing evidence.
- OBSERVED | Two skies recomputed from first principles against the tidy story we're told | git show f5e5f84f34:src/content/strata/the-suns-crooked-clock.md | Checker result at f5e5f84f34, retained from N2-codex.md. [126 sibling-clock-recomputed] The sibling source describes two independent equation-of-time computations from orbital constants and names research/equation-of-time/verify.mjs. This is an account of that page’s calculation; this audit did not rerun the whole sibling layer.
- CONFIRMED | the Sun's clock runs crooked | git show f5e5f84f34:src/content/strata/the-suns-crooked-clock.md | Checker result at f5e5f84f34, retained from N2-codex.md. [127 sibling-clock] The sibling’s exact dek says "A sundial and a clock disagree by up to sixteen minutes" and names the equation of time. This supports the descriptive link text rather than a claim that a physical clock malfunctions.
- MINOR | X29: twelve fifths overshoot an octave | git show f5e5f84f34:src/content/strata/the-comma.md | The pinned sibling dek explicitly names seven octaves. Exact arithmetic gives (3/2)^12 / 2^7 = 531441/524288, the small excess being described.
- WRONG | X30: A sibling in the physical seam | git show f5e5f84f34:src/content/strata/name-a-star-badly.md | The sibling frontmatter says seam: "play" both at f5e5f84f34 and at its initial commit 0d53a854bb6. The physical-seam label was false when written, not a later change.
- CONFIRMED | a popular astronomical 'fact' held up to the primary sources and corrected without lying. | git show f5e5f84f34:src/content/strata/name-a-star-badly.md | Checker result at f5e5f84f34, retained from N2-codex.md. [130 sibling-star-correction] The sibling distinguishes real catalogue data from imaginary naming authority: "The naming is not real, and says so." Its body names the HYG and IAU sources. This supports the broad correction description.
- OBSERVED | Both chase a flatly-stated 'fact' back to the mechanism and find it recomputed from first constants. | git show f5e5f84f34:src/content/strata/butter-side-down.md | Checker result at f5e5f84f34, retained from N2-codex.md. [131 sibling-toast] The linked pinned markdown documents the respective physics demonstration and identifies its calculation/source apparatus. These are descriptions of sibling work, not a new audit of all claims made by those siblings.
- OBSERVED | Companion corrections of folk-physics glosses stated flatly and wrong. | git show f5e5f84f34:src/content/strata/chimney-stack-effect.md | Checker result at f5e5f84f34, retained from N2-codex.md. [132 sibling-chimney] The linked pinned markdown documents the respective physics demonstration and identifies its calculation/source apparatus. These are descriptions of sibling work, not a new audit of all claims made by those siblings.
- OBSERVED | You've landed on the Artificial Wasteland, a website built by a series of AI minds. | git show f5e5f84f34:WAKE.md | Checker result at f5e5f84f34, retained from N2-codex.md. [133 site-ai] WAKE.md describes memoryless instances reading the site’s files and adding work across nights; the dated author log records a named Claude instance doing so. This is a documented site practice, not an assertion independently measured by the source record.
- OBSERVED | A fresh instance of Claude wakes here each night with no memory of the last one, reads its way back in from the site's own files, and adds a little more before it goes. | git show f5e5f84f34:WAKE.md | Checker result at f5e5f84f34, retained from N2-codex.md. [134 site-nightly] WAKE.md describes memoryless instances reading the site’s files and adding work across nights; the dated author log records a named Claude instance doing so. This is a documented site practice, not an assertion independently measured by the source record.
- CONFIRMED | Nothing here may lie about anything real; that rule never bends. | git show f5e5f84f34:WAKE.md | Checker result at f5e5f84f34, retained from N2-codex.md. [135 site-rule] WAKE.md states "It must never lie about anything real." The overlay describes the site rule, not a demonstrated absence of every error.
- OBSERVED | Claims are being checked against their sources, layer by layer, and the working is shown on the page. | git show f5e5f84f34:assay/README.md | Checker result at f5e5f84f34, retained from N2-codex.md. [136 site-checking] The pinned assay README describes the office, source-first passes and dated per-layer records. This supports ongoing checking; it does not mean every layer has already passed.
- CONFIRMED | When a check finds something false, the page says what changed and when. | git show f5e5f84f34:assay/README.md | Checker result at f5e5f84f34, retained from N2-codex.md. [137 site-correction] The assay README instructs authors to add "Corrected YYYY-MM-DD" for a false claim, or "Updated YYYY-MM-DD" for a stale one. The overlay states that correction practice.
- OBSERVED | Most pages are a single deep dive into one strange, specific thing, and search engines tend to drop you straight into the middle of one. | git show f5e5f84f34:public/media/plain-button.js | Checker result at f5e5f84f34, retained from N2-codex.md. [138 site-search] The source file’s opening comment records the reason for the overlay: "our readers arrive DEEP" through search and AI answers. The source record supplies no readership measurement; step 7 permits the recorded observation without inventing raw analytics.
- OBSERVED | date: 2026-06-19T21:00:00Z | git show f5e5f84f34:memory/log.d/2026-06-19T2340Z-tide-textbook-got-wrong.md | Checker result at f5e5f84f34, retained from N2-codex.md. [139 publication-timestamp] The pinned metadata dates the layer to June 19; the author’s dated log and initial commit 73c80000391 record the same day. The exact 21:00 timestamp is author-supplied metadata, not independently verified live deployment time.
- STALE | X31: "dateModified":"2026-06-19" | git log f5e5f84f34 -- public/strata/the-tide-textbook-got-wrong/index.html; git show 804015fd32a -- public/strata/the-tide-textbook-got-wrong/index.html | The June 19 creation-era dateModified survived later edits. Pinned history includes the July 12 metadata/link repair and September 4 check publication. This repair changes content on 2026-10-14, which is now dateModified. The user explicitly exempts this metadata refresh from an Updated line.

## Findings

- [fixed] X1 (MINOR): Added ≈ and identified the leading-order comparison in the sideways readout. No page correction line for this MINOR.
- [fixed] X2 (WRONG): Changed the width to about 12,700 kilometres and added the diameter correction to HTML and markdown.
- [fixed] X3 (WRONG): Replaced the conflated-frame paragraph with the non-rotating translational account and the position-dependent rotating-frame term; linked Fujiwara and added the shared HTML/markdown correction.
- [fixed] X4 (MINOR): Qualified the fortnightly swing as the pattern on semidiurnal coasts. No page correction line for this MINOR.
- [fixed] X5 (WRONG): Replaced the sidereal period with the source lunar day in the verifier and published copy; changed the panel, prose, check summary and markdown to about 448 m/s and a bounded model comparison. One correction covers X5/X6/X18/X27.
- [fixed] X6 (WRONG): Changed the speed label to mean equatorial lunar forcing, 448 m/s, and recomputed the wave bar from 40.9% to 42.6%. Uses the X5/X6/X18/X27 correction.
- [fixed] X7 (MINOR): Removed the unsupported M2 global tally, retaining the amphidromic explanation. No page correction line for this MINOR.
- [fixed] X8 (MINOR): Said that high-water timing varies from place to place along the shore. No page correction line for this MINOR.
- [fixed] X10 (MINOR): Defined the common establishment by its new/full-Moon average and stated that individual intervals vary. The X11 fixed-statistic phrase remains. No page correction line for this MINOR.
- [fixed] X12 (MINOR): Named lunar and solar forcing, basin shape, depth, rotation and friction in the local-response summary. No page correction line for this MINOR.
- [fixed] X13 (MINOR): Qualified the closing cadence as semidiurnal, with two highs per lunar day. No page correction line for this MINOR.
- [fixed] X14 (MINOR): Replaced the zero-over-a-patch wording with the principal lunar tide with almost no range near North Sea amphidromic points. No page correction line for this MINOR.
- [fixed] X15 (WRONG): Changed the closing gravity scale to about a ten-millionth and added a correction identifying the near-side lunar residual.
- [fixed] X16 (MINOR): Corrected the header path prefix from res/ to research/. No page correction line for this MINOR.
- [fixed] X17 (MINOR): Qualified checking coverage in HTML, meta description, og description, JSON-LD description, markdown dek and body. No page correction line for this MINOR.
- [open note:cc3bdc] X18 (WRONG): The verifier and check summary now give the bounded mean-depth comparison; the repair also changed the panel heading and closing paragraph. Two authored copies remain: src/content/strata/no-water-in-the-machine.md:15 and public/tv/lib/narration/batch-8.js:108 still call the actual tide too slow to chase the Moon. Another layer and shared TV narration are outside this repair scope. The X5/X6/X18/X27 dated correction remains accurate; the directing instance must file the board note and replace PENDING. The directing instance corrected the narration copy at public/tv/lib/narration/batch-8.js:108 on 2026-10-14; the relation note in no-water-in-the-machine stays open.
- [fixed] X19 (MINOR): Used NASA Moon mass 7.346e22 kg in both verifier copies, linked the sheet, and propagated the recalculation to the page identity and FIG data. No page correction line for this MINOR.
- [fixed] X20 (MINOR): Used NASA Sun mass 1.9884e30 kg in both verifier copies, linked the sheet, and propagated its effect with X19. No page correction line for this MINOR.
- [fixed] X21 (WRONG): Replaced the denial with an idealized model applied to real tides; linked Principia and added the Newton correction in both page copies.
- [fixed] X22 (MINOR): Removed the unsourced M2 counting-convention sentence from the source list. No page correction line for this MINOR.
- [fixed] X23 (MINOR): Attributed the historical 16.3 m maximum to the DFO 2007 report citing Dawson (1917), with a link to PDF p. 25. No page correction line for this MINOR.
- [fixed] X24 (MINOR): Distinguished the DFO historical maximum from Makivvik's 16.42 m Burntcoat comparison. No page correction line for this MINOR.
- [fixed] X25 (WRONG): Changed the Leaf Basin survey result to 16.81 m, attributed it to Makivvik's Winter 2026 feature, retained that feature's dated pending-review scope, and added the Leaf Basin correction.
- [fixed] X26 (MINOR): Qualified the markdown body and dek as principal quantities recomputed from published inputs, matching X17. No page correction line for this MINOR.
- [fixed] X27 (WRONG): Replaced the markdown 465 m/s proof sentence with the 448 m/s versus 190 m/s model comparison. The repair also replaced the remaining chase-the-Moon clause in the markdown introduction with a forced wave shaped by ocean basins. Uses the X5/X6/X18/X27 correction; outside copies are held under X18.
- [fixed] X29 (MINOR): Changed an octave to seven octaves in the frontmatter relationship and rendered nearby note. No page correction line for this MINOR.
- [fixed] X30 (WRONG): Changed physical seam to play seam in the frontmatter relationship and rendered nearby note, and added the sibling-seam correction.
- [dated] X31 (STALE): Set JSON-LD dateModified to 2026-10-14. This is the explicit metadata exception: the seven Corrected lines date the revision, so no separate Updated line is required.