Every Building in Crapaud

Crapaud, Prince Edward Island is, as I’ve written about at some length, a round municipality.

According to the History of Crapaud, the boundary of the village was set as follows:

It was further decided that the incorporated area should include all land and water within a half mile radius of Crapaud Bridge, which spans the Westmoreland River, on the present course of Highway Route No. 9.

To ensure that OpenStreetMap’s representation of Crapaud aligns with this description, I moved the point marking Crapaud to 46.2398387, -63.4997392, the centroid of the circle that describes the boundary:

OpenStreetMap showing the place marker for Crapaud

Eagle-eyed readers will note that this point falls about 30 meters east of “Crapaud Bridge, which spans the Westmoreland River,” which is where history describes it. It turns out that proclamation in the Royal Gazette of Crapaud’s incorporation refers only to “Crapaud Corner,” without a more specific geographic location; when digital cartographers of yore created the Crapaud municipal boundary in its contemporary digital form they thus had to take their best guess, and what you see in OpenStreetMap is the boundary they came up with.

With the centre of Crapaud now fixed (at least close to) its proper location, and with the work I’ve been doing all winter long to fill out the roads, buildings, driveways, sheds, trees, rivers and forests of Crapaud in OpenStreetMap, I can now use the lovely and powerful Overpass Turbo tool to do some interesting things.

For example, here’s a query to extract all of the buildings in the village:

  way["building"](around: 804);
out body;
out skel qt;

The key part here is the (around: 804), which says “include everything within 804 metres of this node.”

It so happens that 804 metres is 0.5 miles. So this says, in other words, “in Crapaud.”

On a map this looks like this:

Overpass Turbo showing all the buildings in Crapaud

Exporting the results as GeoJSON results in a file that can then be imported into geojson.io:

All the buildings in Crapaud, visualized in geojson.io

Or I can import the GeoJSON file into QGIS, and visualize it with public GIS data, like the 1900 forest layer, something that shows that the subdivision of Sherwood Forest (in the lower-left) used to actually be a forest:

Crapaud with the 1900 forest layer

But it’s not only buildings: this query shows polygons where residential land use has been tagged:

Crapaud residential land use in Overpass Turbo

And this query extracts all the points marked as individual trees (as opposed to areas marked as “wood”):

Trees in Crapaud in Overpass Turbo

I’ve so long thought of OpenStreetMap as a map, and of course it is that.

But it’s also a database with a powerful set of open tools that use open formats, meaning that the effort to keep the map up to date has all manner of unintended other benefits.

Prince County Hospital For the Win

Longtime readers will recall that in 2010, thanks to the good graces of my friend Joan, I came into possession of the tiny letterpress that was formerly the heart of the Prince County Hospital print shop.

In addition to the Adana Eight Five press itself, there were various bits and bobs of letterpress type, spaces, and ornaments, much of it stored, as befits its former home, in medical specimen jars.

One of the items I purchased on my visit last month to the Museum of Printing in Massachusetts was a small font of sans serif type; at the time I assumed it was 12 point, but, taking it out for a ride this morning I realized it was 10 point. And that it didn’t include anything other than em spaces for spacing material.

I had an inkling that, somewhere buried in the boxes of letterpress ephemera that I’ve accumulated over the last decade was so 10 point spacing; I was right: in a pink Starplex specimen jar on the back of my lowest shelf I found exactly what I needed.

Thank you, Joan. And thank you Prince County Hospital print shop.

A specimen jar of 10 point spaces

Download all public GIS layers for Prince Edward Island and use them in QGIS

Back in 2011 I wrote a script to automate the scraping of the public GIS layers that the Province of Prince Edward Island makes available.

I’ve updated this script now–download it here–to handle the now blessedly simpler way the downloads work now (you don’t need to register to download any longer), and I’ve added the generation of a PyQGIS script that will automatically load all the downloaded layers into a QGIS project, ready for entertainment and delight.

Screen shot of all of PEI's public GIS data layers in QGIS

Inconceivable Complexity

We are watching a livestream of the ECMA folk stage at St. Paul’s Anglican Church across the street.

Our bandwidth at home is beamed across Prince Street from the Reinventorium (in the basement of the Parish Hall of the selfsame church) into an Apple Airport Extreme upstairs, which has an Apple Airport Express extender downstairs that Oliver’s MacBook Air in using for his wifi.

Oliver’s got the livestream playing on his laptop, and is streaming it to our Apple TV.

The Apple TV is connected to our 20 year old analog Sony Trinitron using an HDMI to RCA converter.

Where we’re watching music being performed in the church. Across the street. As it’s happening.

Poisons and (Really Bad) Antidotes

My family doctor has this chart on the wall of one of his examining rooms, one of an interesting collection of old medical artifacts.

I’m deeply suspicious that the cure for cannibis poisoning includes strychnine, itself a poison that is “a highly toxic, colorless, bitter, crystalline alkaloid used as a pesticide, particularly for killing small vertebrates such as birds and rodents.”

That seems like a trick.

Another WestJet YYG to Calgary”

Two Weeks, from The East Pointers, is one of those songs that instantly and naturally finds its place in the canon, filling a void we didn’t know existed.

It also happens to include what I believe to be the first reference to Charlottetown Airport’s IATA code, YYG, in a song lyric:

Monday morning, minus eighteen
Another WestJet, YYG to Calgary
I’d always knew she’d get used to me leaving someday

This solves the perplexing problem of Charlottetown not rhyming with anything.

The song was awarded Song of the Year at the East Coast Music Awards last night, well-deserved recognition.

QR Codes Have Jumped the Shark

On page 73 of the 2019 East Coast Music Awards program there’s a half page advertisement for the PEI Liquor Control Commission:

ECMA program at for PEI Liquor

You will note that a QR Code figures prominently in the design of the ad; while leafing through the program this morning I noticed this, and I pulled out my phone to see what was encoded therein.

For reasons perhaps having to do with the QR Code’s non-standard white-on-salmon presentation, I couldn’t get it to scan; to do anything with it I needed to take a photo of the ad and then doctor the photo on my Mac, inverting the colours to be dark-on-light. Once I did that I could scan the code from my phone, where it unfurled into a link for Shopify’s website:

Scanning QR Code to decode shopify.com

I alerted the marketing department at the PEI Liquor Control Commission, and their response was that it was “a stock image that was used to create the ad for the ECMA program, and was not intended to be used as a functional QR code.”

While we all share a laugh about the folly of our government’s liquor regulator accidentally advertising for Shopify, there’s a more profound revelation to be gleaned here, and that is that QR Codes, always questionable to begin with, and of so limited a practical utility as to approach none, have now become digital tchotchkes so meaningless that there is apparently very little risk in dropping random ones here and there, safe in the knowledge that nobody’s ever going to scan them.