Hi Runemage, the masonry PAB refers to, or rather quotes the Bords regarding, is the actual well surround itself not the modern 'bus shelter' building surrounding the well.
If you look at the pictures at the top of this page you will see that the 'floor' of the sunken well surround is cruciform in shape and into that, just through the mass of leaves and stuff, you may be able to pick out the oval outline of the actual well housing itself (the third picture gives the clearest view). In the centre of that egg-shaped well housing is the well shaft itself.
As I said the well has been cleared of all that debris now so if anyone with a digital camera cares to go and take a photo to post on here then you will be able to see very clearly the oval 'egg' shape of the well.
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