I've been re-reading The Goat Foot God, and as is often the way with Dion Fortune's novels have come across a couple of references I've never noticed before: the 'lines of force' and 'lines of power' that she describes as running across the land between ancient sacred sites. She must be referring to what we now call ley lines, and perhaps she was aware of Alfred Watkins' seminal work on this phenomenon as I believe he first wrote about them in the 1920s.
'Ley hunting' was very popular a while ago. I remember once joining a local group of ley hunters and we had huge fun, not least because a surprising number of lines seemed to pass through village pubs….
So far as I am aware less is made of them now, although perhaps I'm out of touch? I don't think it's a subject Dion Fortune mentions elsewhere but it occurs to me that they are a - literally - vital part of the etheric body of the Earth, and this was something she was much concerned with, particularly in her work with the Planetary Being and the Planetary Entity. I'd be interested to learn if anyone has taken up this aspect of her work.
All good wishes,