BigVern wrote:
Quote:
Wouldn't Open Street Map have the railways?
Unfortunately not. To the best of my knowledge the course taken by the old Ohrid line was never shown on OSM and in other parts of (former) Yugoslavia where the Steinbeis and Dubrovnik routes were previously clearly shown, these appear to have been removed, for reasons unknown. The pitfalls of Open source, as I notice abandoned railways have also been removed where previously shown in other countries - as diverse as the UK and Australia.
I see. With OSM it's always down to the contributors, of course. You may find fascinating details, like accurate track plans of tram depots, to the last piece of rail, for a place strictly off-limits to the public. I wonder...
Abandoned lines, if attributed correctly, should still be rendered - OSM will never throw away valuable data - but may not be very easy to detect.
For the "Greek Datum", I have discovered further information which looks more promising. It will need some extension to my datum shift class but I think it's worth a try.
Have you noticed that there are two longitudes marked on the Yugoslavian maps, black and blue? The original black is east of the Paris Meridian, while blue is east of Greenwich. That's a most interesting piece of history. On the European continent, under influence of the French revolution, land cartography was based on a longitude origin in Paris, originally 20 degrees east of Ferro (El Hierro), later somewhat adjusted, the western end of the antique world. There was an international conference in the late 19th century where the Greenwich meridian was agreed upon worldwide but it still took decades before it became the mapping standard everywhere. Germany switched from Ferro to Greenwich (and from Cassini/Soldner to Gauss/Krüger) in the late 1920s.
A few years ago BBC 4 showed a 3 part documentary series on the history of maps, very informative
. There is also a short article on the Paris Meridian in
wikipedia.