Map Evidence Lab

Maps

Historical maps, projections, geographic evidence, scriptural cosmology, and institutional symbolism — with sources, uncertainty, and clear separation between artifact facts and interpretation.

Methodology

Sources & methodology

Everything you see in the Map Evidence Lab is traceable back to a named dataset, a published projection formula, or an archival scan with a repository record. This page is the ledger.

Primary coastline dataset

Natural Earth 1:110m coastline / countries (via world-atlas TopoJSON) Public domain (Natural Earth). Distributed via the world-atlas@2.0.2 npm package as TopoJSON, converted at build time with topojson-client.

naturalearthdata.com →

Projection formulas

Each projection is implemented via d3-geo / d3-geo-projection. What each preserves and distorts is quoted in the Projection Lab; the source function is listed here.

ProjectionCreatorDateImplementation
Equirectangular (Plate Carrée)Marinus of Tyre (attributed)c. 100 CEd3-geo · geoEquirectangular
MercatorGerardus Mercator1569d3-geo · geoMercator
Equal EarthŠavrič, Patterson & Jenny2018d3-geo · geoEqualEarth
RobinsonArthur H. Robinson1963 (adopted by NGS 1988)d3-geo-projection · geoRobinson
Orthographic (globe view)Hipparchus (attributed)c. 200 BCEd3-geo · geoOrthographic
Azimuthal Equidistant · North PolePostel (attributed)1581d3-geo · geoAzimuthalEquidistant · rotate [0,-90]
Azimuthal Equidistant · South PolePostel (attributed)1581d3-geo · geoAzimuthalEquidistant · rotate [0,90]
Gleason layout — analytical approximationd3 azimuthal equidistant, N-pole centered (analytical stand-in)n/aAnalytical stand-in only. See the Gleason tab for the authentic archival scan (Boston Public Library, commonwealth:7h149v85z).

Sphere constants

  • Mean radius R = 6371.0088 km (WGS84 mean).
  • Great-circle distance uses d3.geoDistance (spherical law of cosines).
  • Axial tilt slider on the Globe tab ranges ±23.5°; day/night terminator uses current UTC hour to compute the sub-solar meridian.

Discipline for exhibits

  • The authentic 1892 Gleason map is only ever displayed as an archival scan (Boston Public Library, commonwealth:7h149v85z) with its rights statement. It is never redrawn, cleaned up, or substituted with a schematic or AI reconstruction.
  • Historical maps carry: creator, date, repository, catalog URL, rights statement, and any georeferencing status (approximate / anchored / not georeferenceable).
  • Where a historical map cannot be georeferenced, it is not overlaid on any coordinate system — it is displayed on its own with interpretive notes.
  • Overlays are only permitted within one projection. Different projections force side-by-side or difference views.
  • An organization's use of a polar-azimuthal or circular emblem is documented as an emblem, not evidence of institutional belief.
  • User submissions are held in a separate lane until reviewed; nothing enters the archive without founder approval.

See also About our method for the site-wide rules on evidence, findings, and corrections.