Hi,
It might help if you could explain what it is you are thinking of. The Astley workings involved a good number of different coal seams, each of which had its own extent.
This is one example.
🔗107306[linkphoto]107306[/linkphoto][/link]
This is not to scale, but gives an idea of the vertical relationships.
🔗107292[linkphoto]107292[/linkphoto][/link]
Trying to show all the workings on one plan results in a confusing mess of lines - I know, I once tried to combine the tracings of various seams onto one, but there are too many tunnels, etc. on top of one another to be readable.
Then there are the effects of the dip -primarily towards the south and the faulting which meant that the same seam might be worked in more than one area.
I have somewhere in my disc archives some scans of part of my attempt which I can upload to give a flavour of the problem.
Grahami
The map is the territory - especially in chain scale.