Multispectral Analysis Reveals Lost Details on a 16th-Century Portolan Chart

Excerpt from an enhanced version of Bartolomeu Velho’s portolan chart of the east coast of North America, ca. 1560. Compare with the original. Library of Congress.

The Library of Congress reports on how its Preservation Research and Testing Division used multispectral imaging to bring out previously illegible place names on a 16th-century portolan chart of the east coast of North America. Initially the PRTD was brought in to confirm that the chart was legit before the Library purchased it (which it did last fall), but the faded iron gall ink in some areas of the map suggested obscured details that further analysis could draw out and place names that could be made legible again. According to the article, this represents the first time the Library has posted an enhanced image of one of their holdings.

‘An Impossibly Heavy, Large Silver Globe’

“Of all the globes in the Geography & Map Division’s collections, there is one that has always caught my eye: an impossibly heavy, large silver globe tucked away in our stacks, that stands without any depiction of the earth’s physical features at all. The large silver orb instead displays only a coordinate system grid composed of unlabeled latitude and longitude lines.” Meagan Snow writes about the unlikeliest of globes in the Library of Congress’s collection: a precisely machined 34-inch blank metal globe. What on earth it was it used for? Answer unclear: “The intended use of the globe is described as ‘for earth study.’”

Geofence Warrants Found Unconstitutional by One U.S. Federal Court

A U.S. federal court has held that geofence warrants are unconstitutional under the Fourth Amendment, finding that they fit the definition of general warrants that are “categorically prohibited” by that Amendment. EFF, TechCrunch. Geofence warrants, you may recall, require a data provider (usually Google) to identify all users in a given area during a given time period. While ruling them unconstitutional, the U.S. Fifth Circuit Court of Appeal nonetheless allowed evidence collected under a geofence warrant in the case under consideration, citing the good-faith exception, given the novelty of such warrants at the time and the lack of legal guidance available to law enforcement: see the court’s decision.

Geofence warrants are now in something of a grey area: the Fourth Circuit upheld geofence warrants’ legality, at least under certain circumstances, only last month. The two cases may not be an apples-to-apples comparison, but even so the constitutionality of location data searches may take a while (and the Supreme Court, eventually) to sort out.

OpenStreetMap Is 20 Years Old

OpenStreetMap is celebrating its 20th anniversary today. It was originally created in response to restrictive Ordnance Survey licensing in the U.K., in a context that seems unrecognizable today. Founder Steve Coast writes about the anniversary (mirror link). “Allowing volunteers to edit a map in 2004 was simply anathema and bordering on unthinkable. Map data was supposed to be controlled, authorized and carefully managed by a priesthood of managers.”

Tim Walz Is a Huge GIS Nerd

Yesterday, U.S. Vice President and Democratic presidential nominee Kamala Harris announced Minnesota Governor Tim Walz as her running mate. Among other things, Walz is a former social studies teacher and early adopter of GIS as a teaching tool, and has nerded out on geography and GIS throughout his political career, both in the U.S. House of Representatives and as governor. Walz even spoke at the 2024 Esri User Conference in San Diego last month (as someone married to a high school teacher, I can say this: he totally talks like a high school teacher). See also this summary of the talk, and Walz’s map nerdery in general, in the Minnesota Reformer.

The Babylonian Map of the World

The British Museum has posted this video about the Babylonian Map of the World, a nearly 3,000-year-old clay tablet inscribed with Akkadian script and a schematic map that is often called the oldest map in the world. The video, part of the Museum’s Curator’s Corner series, focuses on the discovery in 1995 of a missing section of the tablet, and what the inscriptions mean. Here’s the Museum’s collection listing for the tablet.

Previously: An Ancient Map of the Mesopotamian World.

Null Island as Easter Egg

Stamen Maps

Null Island is an inside joke among cartographers: an imagined island situated at 0° latitude, 0° longitude, where maps suffering from data glitches point themselves. If your map is centred on Null Island, something has gone wrong. So of course mapmakers have been having some fun with it—after all, it’s not something you could stumble across by accident. In a blog post, Alan McConchie of Stamen Maps delves into the lore and history of Null Island and its status as an Easter egg on the Stamen Maps platform, where it takes the shape of the island from the Myst game.

(As an update to my 2016 post on Null Island: Alan reports that the buoy at 0°, 0° has ceased to be. Also, the Null Island website, complete with flag, has moved here.)

The Useless Grandeur of Coronelli’s Great Globes

Constructed in the 1680s for Louis XIV, and measuring nearly four metres in diameter and weighing a couple of tons apiece, Vincenzo Coronelli’s great globes “are a simply amazing celestial and terrestrial pair,” writes Matthew Edney, who saw them at the Bibliothèque nationale de France in 2019. But, he goes on to say,

[T]he globes were effectively useless. Their imposing grandeur made them completely the wrong size to be used effectively. Smaller globes—made with diameters between 0.075–1.7m (3–67″)—could be easily turned to show specific parts of their convex surface. Or, people could enter within much larger globes, called georamas, turning themselves around as necessary to see all parts of the earth on the concave interior surface. Coronelli’s globes were far too large for the former, and far too small for the latter.

This unavoidable reality inverted the usual physical relationship between viewers and globes, undermining the viewer’s usual sense of intellectual domination and converting the globe-viewing experience to one of awe and amazement. As a result, no-one really knew quite what to do with them[.]

Their difficult size and limited utility is why they’ve spent most of their 340-year existence hidden from view, though they’ve been on display since 2005 at the BNF’s François-Mitterrand site (see the above BNF video, in French).

A Map of Wildfire Damage in Jasper, Alberta

Municipality of Jasper

Fire forced the closure and evacuation of Jasper National Park this week, and the Jasper townsite itself was directly hit by flames on Wednesday. Parks Canada estimates about a third of the town’s structures have been destroyed. Municipal officials released a preliminary map today showing the damaged and destroyed buildings in the town. They stress that the information “is based on the damage that is visible from the street. We have not been inside buildings or seen the backside of properties. There may be additional damage to homes and businesses that isn’t visible from the street. Buildings marked as ‘not damaged’ on the map could also have internal damage caused by smoke and water. Consider this a preliminary description of properties affected in Jasper.” CBC News coverage.

Remembering MapQuest

The tenth installment of James Killick’s “12 Map Happenings that Rocked our World” series focuses on a company James actually worked at: MapQuest, which grew very, very rapidly between its launch in 1996 (James outlines its antecedents) to its IPO and acquisition by AOL a few years later. And then:

The new management seemed to have very little interest in anything to do with MapQuest, particularly as it related to product road map and strategy. And with the layoffs and hiring freeze there weren’t enough resources to do anything substantial even if there was a good plan.

I tried to make matters clear and pleaded with the powers that be: MapQuest was a site built on map data but it didn’t make maps. In fact 98% of the map data was licensed from third parties. I knew MapQuest had to build a moat around the product otherwise someone else could swoop in, license the same data and build a better product.

And you won’t win any prizes for guessing who did.

Previously: Remember MapQuest?

Terse Directions

Adding to the discussion as to whether online maps’ directions are too exhausting, Tim Bray argues for terse directions: “When I’m navigating an area I already know about, don’t give me turn-by-turn, just give me a short list of the streets to take.”

Right now, Google Maps insists on turn-by turn, with three warnings for each turn. It’s dumb and annoying and interrupts whatever music or show I’m listening to.

What I want is to get in the car and say “Short directions to New Brighton Park” and have it say “Take Main to 12th to Nanaimo to 1st to Renfrew to McGill.” Then when I’m driving, I’d get one vocal warning a block out from each turn, like “Next left on Nanaimo” or some such.

Previously: ‘Map-Splaining’.

Apple Maps on the Web

Apple announced yesterday that Apple Maps is now available on the web as a public beta. Prior to this it was mostly available through its iOS, iPad and Mac apps, except that developers have been able to embed Apple’s maps on their websites through the MapKit JS API for several years now. Those embedded maps can now point to the web version, “so their users can get driving directions, see detailed place information, and more.” Limited browser and language support for the time being.

Historical Maps of London

Tudor London: The City and Southwark in 1520. Historic Towns Trust.

Londonist does a good job introducing us to two maps of old London published by the Historic Towns Trust a few years ago—a map of medieval London (1270-1300) published in 2019, and a map of Tudor London (1520) published in 2018 (and updated in 2022). The Historic Towns Trust publishes many maps of British towns and cities—historical maps, not reproductions of old maps (in fact, Londonist points out that no maps of London prior to about 1550 currently exist). The Trust’s London maps are also available as overlays on the Layers of London online map: Tudor, medieval. Some maps from the Trust’s British Historic Towns Atlas, which began publishing in 1969 and the earliest volumes of which are out of print, are also available as PDF downloads; here’s the page for London.

Google Maps Navigation Updates

Google Maps is introducing a speedometer and speed limits to iOS and Carplay; the feature has been on Android since 2019. Meanwhile, Google has pushed back on the claim from one user that pop-up ads were turning up while navigating with Google Maps; rather, they say it was an instance of “promoted pins” that (should) only pop up if tapped on. 9to5Google: “we were able to replicate the exact same UI by tapping on a location on the map, so it seems the screen was either touched by accident or a glitch was at play.”