“The Wife of Usher’s Well” is, in effect, a ghost story,"
I think this beautiful ballad is a little more than that - for me it's a superb example of a whole genre of songs and tales of 'the unquiet dead', describing the effects of 'over-mourning' the dead
It even made it to the silver screen, one of the bet examples (imo) being the gentle English 'Truely, Madly, Deeply' - vastly superior to the cack-handed and mawkish Hollywood blockbuster, 'Ghost', made around the same time

Technically, the sons aren't 'ghosts', as their mother's over-mournng has not allowed them to die properly and pass to their rest
They are not threatening, as ghosts are generally considered to be, not frightening in any way - they have returned to close their lives properly rather than having died away from their loved ones unseen

Travellers told us how they kissed the foreheads of the corpses so they could be 'seen off' in peace
If they met a funeral on the road they would turn and follow it for six steps to save 'the feller in the box' the bother of chasing after you to say goodbye'
Twenty years ago I attended Clare fiddle player, Junior Crehan's very traditional wake - the mirrors and shiny surfaces in the room were all covered and the window was left wide open so, when the time came, the spirit could depart freely without 'bumping into things'
THere was a 'correct war of doing things that had to be adhered to for the sake of both the departed and those left behind

There is an equally beautiful 'prequel' to this ballad , 'The Clerk's Twa Sons of Owsenford' explaining how the boys died - well worth looking out for - it's occasionally claimed they are the same ballad broken in half
Can't find it on UTube, but MacColl makes a fine job of it on 'Blood and Roses (vol 4)
Jim Carroll