I wish to map data from the 1911 census. Where can I get boundary data for, for example, the DEDs or the townlands? Alternatively, a single coordinate for the DED or townland would suffice.
If this isn't possible, would such data be available for Griffith's Valuation?
Oooh, good question. I've often wished there was a map on the census website showing those boundaries.
This data must exist in the National Archives, but Shane will probably have insight.
I definitely wouldn't use the Griffiths maps because they're 40-50 years older and they use civil parishes.
I'm not sure if the EDs here are what you're looking for.
or possibly maps.openstreetmap.ie
there are maps showing DEDs on logainm.ie, although slightly later and not very detailed - see Toponymy resources, scroll down to the first 4 maps under 'Historical maps > Boundaries'.
I've a joined up version somewhere if that might be of interest
You can download shapefiles with coordinates from the Irish Townlands/Openmapping website for townlands, civil parishes and Electoral district (c85% coverage), but I dont know the status or date for the DED data.
I'm actually working on a census search tool which allows searches by street/townland, although not directly linked to maps at the moment...
This is still not officially launched, but https://irishfamineproject.com maps the data from pre/post famine censuses per parish, with search/location and also a table of all info - you could contact the author for more info.
I don't want to hijack this thread with talk of this new website, which looks great. Danbo! - if you're happy, I'll split it off into a different thread.
Nah, not to worry, I removed the shilly bit, I think rest of post is still relevant, sorry
Thanks for your suggestions. I wish to plot all the DED's for the 1911 census. So, I have tried using the google and the open street map geocoders for all the DEDs in Donegal just to see how I might get on. I am doing this using a Python script. Here is the result:
The first column is the name of the DED. The green columns pertain to Google and the blue Open Street Map.
If I look up "Ardara, Co. Donegal, Ireland" with Google, I get an exact match and I am therefore content with the coordinate: 54.7671456 -8.4092864.
If I look up "Altnapaste, Co. Donegal, Ireland", Google gives me the location: "Meenagrauv, Altnapaste, Co. Donegal, Ireland" which I presume is also, acceptable.
However, I reject "Ballymacool, Co. Donegal, Ireland"'s result of "Ballymacool, Sallaghagrane, Letterkenny, Co. Donegal, Ireland" as I am not sure if there are other Ballymacool's in Donegal. But maybe I shouldn't be so strict... what do you think?
I dont seem to get on as well using the above rules with Open Street Map, but it is interesting to see that I get lots of ED's. For example,
"Three Trees, Co. Donegal, Ireland" gives: "Three Trees, Three Trees ED, Inishowen, County Donegal, Ireland" which my algorithm currently rejects but I should probably accept any match with ED in it I think.
Any suggestions as to how I might proceed?
My algorithm isn't fool proof . "Cross Roads, Co. Donegal, Ireland" is not the same as Google's match: "Avaltygort, Cross Roads, Co. Donegal, Ireland" nor is it the same as Open Street Maps match of "Cross Roads, Gleneely ED, Stranorlar, County Donegal, Ireland". It's actually an old name for "Falcarragh, Co. Donegal, Ireland" a long, long way away from the aforementioned matches. Maybe I also need to use the townloads within the DEDs to get a more reliable coordinate...
I applaud your efforts.
The IGRS has a copy of the 1901 Townland index (as opposed to the more freely available 1851) which should help differentiate townlands with the same name. They were revised for 1901.
OK, so here is how I am getting on now. I am looking at the county of Carlow as I am limited as to the number of lookups I can do using Googles geolocation.
Remember what I am after - I am looking for a coordinate for each ded in the 1911 census.
So, my algorithm is as follows:
A) I look to see if I can get an exact match for the name of the DED using google's geocoder. For example, "Ballon, Co. Carlow, Ireland" is such an exact match.
B) If this fails, I get all the townlands for this DED but throw away any which have the same name as a townland in another part of the county. Townlands like "Glebe" and "Main Street" are very common with a county. I then try to get an exact match for the townlands in this DED. For example, "Carrickslaney, Co. Carlow, Ireland" is such an exact match for the Kilbride DED. I then take all the exact matching townlands, find the coordinate at the center of theses townlands, and take the coordinate of the townland closest to this center as the coordinate for the DED. For example, "Barragh, Co. Carlow, Ireland" was this towland for Cranemore.
C) If I don't get any exact matches, I just take a list of townlands for the DED where I get an inexact match. For example, "The Numbers" matches "The Numbers, Carlow, Co. Carlow, Ireland". Again I take all the inexact matches, find the center and take the closest townland.
Here is the result for Carlow:
And here they are mapped, with Green = exact match on ded, Yellow = exact match on townlands, Red = inexact match on townlands:
What do you think? Can I improve the algorithm? I wonder how this will work in the likes of Dublin...
It's looking good. I wonder about the boundaries of these DEDs though. It would be useful to see an outline of exactly where somewhere encompassed.