Tried to learn it once, was reading a ghost story about a certain horse drawn coach.
If you follow it, it supposedly leads you into a tree or rock wall.
Been years since then, and haven't continued it since.
I was 6 or so at the time, and the books I studied were old at the time.
I'm now 29, and honestly don't remember a durn thing I learned.
Horse drawn coaches?
Darby O'Gill and the little people?
That scared the b'jaysis out of me as a child! :-)