Category: QGIS

As everyone will no doubt have heard, Scotland voted in a referendum on independence on the 18/09/2014. The vote was no, but it presents an excellent opportunity to visualise election results.

Addition From Black

We start with a black background since in RGB 0,0,0 is pitch black. Then we have 2 datasets with graduated colour scheme from completely transparent to completely red/blue. We use the percentages per council area to show the split, but using absolute counts could also work. These layers have the blending mode of “Addition” so they stack creating a purple map, with the redder areas voting no and the bluer areas voting yes.

Bar Graph

This is more of a proof of concept than a truly functional map. The bars are created from the polygon centroids as a line symbol. The length of each bar plotted in meters from a calculation of the number of votes * 1000. I found out that this could be more easily created using the diagrams feature, which would produce the same result without the need for creating centroids and allow for more placement options.

Data Driven Opacity and Hue

Simple Red to Blue gradient from the percentage of yes votes. So from 30% to 70%, providing a nice gradient of the vote outcome. Above this was place a completely white layer, which had its alpha channel driven by a normalized total voters field. So Glasgow has a white 100% transparent feature over it, while Orkney has a 0% transparent feature. This symbolises the impact of each councils vote and the result.

In 1654 Joannis Blaeu published volume 5 of his Atlas Novus. The Atlas contained three general maps of Scotland and 46 maps of Scottish counties or regions, making Scotland the best mapped country in the world.

The Blaeu outline was influential on the outline of Scotland for the next decade to come. This is a comparison of subsequent outlines of Scotland before the 1747-1755 Roy Military Survey of Scotland truly surveyed the whole of Scotland.

The maps in this comparison are:

• [1654] – Robert GORDON – Scotia Regnum… (1654 Blaeu)
• 1665 – Nicolas Sanson – L’Escosse Royaume
• 1714 – Hermann Moll – The north part of Great Britain called Scotland.
• 1745 – John Elphinstone – A new & correct map of North Britain
• 1751 – James Dorret – A correct map of Scotland from new surveys

Excluded is the [1687] – Robert Morden – A mapp of Scotland made by R. Gordon because it essentially just follows the Blaeu outline.

In addition a background map was created from OS BoundaryLine (High Water Polyline) and converted to a polygon.

Everything is converted to WGS 84 / World Mercator projection (EPSG:3395).

For more on how the outlines were created:

Georeferencing vector data

For a history of the maps used:

Historic Maps of Scotland from Blaeu to Dorret (1600-1700)

If you are interested in buying a historically amazing map:

Blaeu Atlas Maior of 1665 – Including the atlas of Scotland.

Scotland’s changing coastline: