I was flipping through Owen Jones’s Grammar of Ornament a couple months ago, and my eye was caught by this handsome pattern I had not noticed before. This is Jones’s Plate XLII, in the chapter on designs from the Alhambra in Granada, Spain. He calls it, “Part of the ceiling of the Portico of the … Continue reading Constructing the Pattern on the Sala de la Barca Ceiling →

(This is the math geek part about the Sala de la Barca ceiling. For instructions on constructing the pattern with compass and straightedge, go over to Part 1.) In the process of figuring out how to draw this pattern, I ran into a lot of questions, and had to do more than a little math … Continue reading The Mathematics of the Pattern on the Sala de la Barca Ceiling →

Nord de Guerre Here’s a survey plat made in 1919 by a US Army unit in France. In the aftermath of WW1, teams of American military surveyors produced these as they went around France mapping the grave sites of fallen soldiers. On this plat we can see a number of bearings and distances from the … Continue reading Transforming French WW1 Lambert Coordinates to WGS84 →

This story begins one day when I was assembling a map of the city of Edmonton, Alberta from OpenStreetMap data. It was going to be a big map, a 42″ (106 cm) wide poster for a wall. The data was good, but the standard OSM colours were not. They would work fine for a street … Continue reading Cartographic palettes and colour harmonies →

Now that we know our way around the pattern (go back to Part 1), it should be fairly straightforward to construct with a compass and straightedge. But be aware: any pattern that requires you to construct a pentagon is an advanced challenge. They are trickier to make than squares or hexagons. Here’s what we want … Continue reading Constructing Bourgoin’s Figure 171 – Part 2 →