thinkwhere

Popped along to the official launch of West Yorkshire Archive Service’s (WYAS) Tracks in Time website and their new online mapping application, held at the City Museum. Earlier the prototype was leaked onto Secret Leeds to an enthusiastic response. I’d always been interested in this project, having been made aware of it when I was asked for some advice about it in the very early days of the project, by me living in Leeds, and recently with our work with the New York Public Library georectifiying and digitizing their historical map collection – so it’s really good to see it out there and completed!

Its a nice application (even if it has a bit of an old fashioned/council GIS feel to it) and works well, that used the code from a similar Cheshire Project.  The project is the culmination of some Lottery funding and although the Archive service is for the whole of the county, the project was restricted to Leeds. Gardline Infotech were contracted to do the offline GIS portion, and the folks at WYAS, with Leeds City Council and Cheshire Shared Services who put together the online version.

The system has two map panes, on the left tithe maps and on the right some more modern reference maps.

There is also  layers for land use and who owns what. Users can search for people and get these selected on the map – it’s a great resource. Searches can be exported as CSV file, which gets marks from me. Unfortunately, both these exports and the maps miss out the land value data, which had been transcribed, apparently due to a technical limitation in the software, which is a great great shame. I’d love to be able to compare the price of land as it was then to house prices now.

I think it was Stephanie? from WYAS, who was describing how it was not only people that can be searched, but corporations or other owners. A search for “railway” for example gave results for all those portions of land taken for new railways. Railway companies such as Leeds & Bradford Railway Company and North & Midland Railway are recorded, with land also taken for railway stations. On the map we see that the present day lines of the railways, before the lines were built. Its a particularly good resource for that time of the industrial revolution, and is strong in the north of england where a lot of the industry was taking place.

The 58 hand drawn tithe maps were scanned, georeferenced and digitized. The digitized vectors were tied together with volunteer transcribed apportionment information – over 29,000 records!

The maps are hand drawn.
The maps were scanned by the Coal Authority in Nottinghamshire. They have the largest facility in its kind in Europe. Some of the maps took up the entire table – they were over 3m long!

Tithe maps were not meant to be definative maps of boundaries or for navigation, they were never meant to be a record of rights of ways and roads. As a consequence, these maps have parts where some areas are out by 60m or more. Its also important to remember that the maps are hand drawn. There were only ever 3 copies of each made – one sent to London, one to the Diocese and one to the Parish. The Archive Service had a copy of all of the maps but sometimes only one of the were found – and some were in poor shape.

We had a chat with the representative from Gardline Infotech whose name I didn’t catch and Peter Lythe, the project manager for WYAS – and discussed some of the challenges.

Georeferencing the maps proved troublesome – in particular where maps had folds and some where the original surveys were inaccurate. The side by side panes help to disguise some of the inaccuracies where they occur. They used the historical buildings data to help pin point some of the areas on the maps, and then used OS MasterMap to get the tie points. Yes, I can hear alarm bells ringing too – by using OS Master Map, the georectified maps are derivative works of Ordnance Survey, and so you’d need to have an OS license to use them.

Gardline used Cadcorp and FME mainly to vectorize the data, and they did a good job.  I don’t think the vectors can be downloaded either – if they were the digitized land parcels vector GIS files would also be under this same license. There was never a requirement to make available these files available to the public at large for free – so nothing wrong happened, just another missed opportunity. The good news is that the transcribed data is separate from the maps and can be accessed and downloaded (without the land values field) – and the scanned source imagery would be free of OS tie-in and it wouldn’t take too much to georectify the source maps (and even remaining ones for the whole county) and vectorize them in a collaborative and open manner, as we’ve seen.

Overall it’s a plus to the city and a marvelous resource of the past for the future.