Mapping Erasure

A Historical GIS of Place, Uncertainty,
and Archival Absence in the Panama Canal Zone

A map of the places, and the infrastructure within them, that were flooded, depopulated, relocated, or renamed during the construction of the canal, and of what now stands on the same ground.

view ?
?
time 1900 ?
showing ? ?
filter by ? ? ? ? ?

Legend: ?
Colour — this view:
Geometry — every view:
striped area = uncertain, drawn at its stated radius
filled area = extent on record (overlaps freely)
dashed symbol = located, but no extent recorded (fixed size, not an area)
hollow rings joined by a line = sources disagree; all claims plotted
Time:
faint = claimed for this year, but no source is dated to it
dotted ring = removed by this year, still shown as a trace
present-day (extant), drawn beneath the historical symbols
Sources: ?
select a source to see only the places it records, ordered from earliest to latest
Unlocated places: ?
documented in the sources but not placed — each shown with the archives that name it and those searched without result
Located places:
places with coordinates, plotted at the selected scale, ordered from oldest founding to youngest; select one to open its record on the map
The archives behind the sources: ?
every institution whose collections were searched for this study, ordered alphabetically; select one to view its collections and the sources drawn from each
This dataset reflects the collections and material consulted for this study. Access varies: some entries record searches of digitized items, while others describe catalogue checks or material requiring a visit. The notes under each collection give the recorded scope and limits of those searches.

How to read this map

Using the controls:
1
Choose a view. Each one colours the same places by a different question. Start is the opening state: choose it again to clear everything and begin afresh.
2
Move the time slider, or press Play, to run from 1850 to 2025. Play slows through the construction decade, where most of the change happens.
3
Show all puts every placement back on screen at once, in whichever view you are in, ignoring the year.
4
Click any place, on the map or in a panel, to open its record card; it turns red on the map. Drag the card by its title bar; close it with the ×, Escape, or a double-click outside.
5
Type in the find box to search both place panels by any name the sources record, so a renamed place still turns up under its earlier name.
6
The showing switch chooses places or the buildings & infrastructure inside them. The filter menus narrow that down further.
7
sources disagree keeps only contested locations. american origin fills the townsites the United States canal authority built for its Gold Roll (mostly white American) and Silver Roll (mostly West Indian Black) workers.
8
In the Sources panel, click a source to redraw the map with only the places it records. Sources and Located places can be sorted by date or A–Z.
9
The dot beside each name carries the colour the map is giving that place right now; unlocated places keep a neutral grey ring. From 2000 a closing tally joins the caption.
10
Each ? explains a control. The page address saves the view, year and filters; it does not save the search text or map position.
The map symbols:

Shape shows how confidently a place is located; colour depends on the current view; opacity shows the state of the evidence for the selected year; places that are absent from the record are still shown as such. Fixed-size symbols do not represent distance on the ground.

1A precisely located feature, drawn as a solid point.
2The same symbol, faint: the place is claimed to exist in this year, but no dated source covers it.
3An extent drawn at the radius its source states, translucent so that neighbouring extents can overlap.
4A striped area: the place lay somewhere within it, but its position is only loosely known.
5A dashed symbol of fixed size: located, but with no extent on record.
6Hollow rings joined by a line: sources place the same feature differently, so every claim is plotted and none is chosen.
7A dotted ring: removed by the year on the slider, but still shown as a trace. Dotted outlines are only used for removed places.
8A dashed halo: an unlocated place that the sources tie to the located place it surrounds.
9Solid red, with the american origin switch on: a townsite the United States canal authority built for its Gold Roll (mostly white American) or Silver Roll (mostly West Indian Black) workers, in any view. A red outline alone marks whichever place's record card is currently open.
10A traced outline: the shape the place actually had, digitised from a historical map or town plan rather than approximated by a circle. Most of the buildings and infrastructure are drawn this way, and a town keeps its traced extent underneath them.
The archives card:
1Institution name
n collections searched · m sources in this study
2Collection name ARC-##
the repository holding it · the years it covers
3how it can be consultednot yet searched
digitized how much of it can be read from a distance
4Holdings:
  • what the collection contains
5Sources drawn from this collection (n):
  • Source title (date)
1Archives are listed at three levels: the institution, the collections it holds, and the sources drawn from each collection. Click any institution in the archives section to open its card.
2Each collection keeps its own identifier and its own origin tag, so a French map held in a United States library is still tagged French.
3How the collection can be consulted, and whether it has been searched yet. The bars say how much of it is readable from a distance; a "searched, absent" claim is only as strong as the archives it was possible to search.
4What the collection contains, in its own terms.
5The sources this study drew from it. Click a source title to redraw the map with only the places that source records, exactly as clicking it in the Sources panel does.
The record card:
1Place name CZ-###
2scale · place type · theme · part of a parent place
A short description of the place, where one is recorded.
3~1890-1913spatial: Lowcommunitywarnings, in red
4at 1910what the slider year means for this place
5Location:
how its shape was drawn, and from what
6Names as recorded:
1907Earliest name 3 sources, first: where it appears
1912A later name the source that renamed it
7Relations:
1906-13part of / near / replaced by another place
8Features within this town (n):
Buildinga hospital, a camp, a roundhouse… each linked to its own record
9Sources (n, across m mentions):
×4Source title (origin; kind of record; ×4 = mentions it 4 times)
10Not found in searches overlapping its lifespan (n):
×1A source made while the place stood that does not name it (origin)
Also searched, absent (n):
made before it existed, after it was removed, or undated
1The place and its ID in the dataset.
2The kind of place, its scale, and the place it belongs to, with a short description where one is recorded.
3Lifespan, how confidently it is located, and whom it housed (Gold or Silver Roll, Panamanian village, or mixed). Red chips are warnings, such as a source made while the place stood that leaves it out.
4What the year on the slider means for this place: attested, only claimed, before its founding, or after its removal. This updates as the slider moves.
5Where its map shape comes from: a stated radius, an extent traced from a map, competing claims, or "no coordinates on record."
6Each distinct name the sources use, earliest first, since renaming is part of these places' history.
7Dated links to other places in this study.
8The buildings, camps and institutions recorded inside a town, each linking to its own record; a feature's card links back to its town.
9One expandable entry per source. Open it to see individual references, dates, confidence and research notes. Unchecked search results are labelled.
10Searches without a result are grouped by whether their dates overlap the recorded lifespan. Their meaning depends on what was searched and how thoroughly; an unsuccessful search does not establish that a place was absent.