The National Library of Scotland’s high-quality scans of historical Scottish mapping have been made available under an Attribution licence, which means they can now be used to trace features for OpenStreetMap in Scotland. While the maps themselves were already out of copyright, the high quality scanned imagery itself was still subject to copyright.
You might think that, with the recent releases of up-to-date(ish) Ordnance Survey mapping in various scales and formats for the whole of the UK, historical mapping is less useful for OpenStreetMap. After all, why use 60-year-old mapping, available in raster form and available at (relatively) low resolutions, when resolution-free vector data, and 1:10000 rasters of the same area are similarly available. But these beautiful old maps contain a lot of detail not on the newer ones, and for large parts of rural Scotland, where roads, rivers and mountain features very rarely change, they will still be enormously useful for completing the more remote parts of the country.
The historical maps can be viewed here. As you zoom in a few levels, the projection changes into the regular EPSG900913 (the tilted north lines are a tell-tale sign) that can be used directly in OpenStreetMap editors such as Potlatch.
Here’s Applecross, a place near Skye in North-West Scotland that I have long wanted to visit. In this particular area, historical imagery (OS 7th Edition) is already available on OpenStreetMap, allowing for tracing, but this is not the case for most of Scotland, as many of the sheets are still in copyright.
National Library of Scotland (Historical):
Ordnance Survey Street View:
Ordnance Survey 7th Edition (Historical):
The current OpenStreetMap Mapnik render: