As an Incredible String Band fan, I can say that Mike Heron wrote 2 versions, one called "Black Jack DAVY" on the 1970 "I looked up" and "BLACK JACK DAVID" on the 1972 album "Earthspan". The former is I think the best, the latter having electric rather than acoustic fiddle, which I prefer; it also has a nice "false ending". Until about 2 years ago this was the only version I had heard, then I heard Woody Guthrie's version, on which Bob Dylan seems to have based his, though with many changes.

I also think "Black Jack Davy" sounds better than "Black Jack David". I imagine "Black" probably referred to hair colour, or complexion, as in "(Black) Jock/Johnnie Armstrong", the notorious Border "Reiver" of Gilnockie, who was hanged in 1530.

I am not aware of the other ISB man (not forgetting Clive Palmer), Robin Williamson, singing Black Jack Davy, though he does sing "Wae's Me for Prince Charlie" and also mentions Johnny Armstrong in a song called "Hughie the Graham", about a Border reiver of that name.

Anyway, the lyrics to the 1972 version as printed on the album sleeve are nearly the same as those posted by Jon Freeman on 17th June 2001, with a few very minor variations, and the omission of the following verse in the 1970 version:

Now fifteen summers was all that she'd seen
And her skin was as soft as the velvet
But she's forsaken her fine fine home
And Black Jack Davy
Singing through the green green trees

1972 version from "Earthspan"

BLACK JACK DAVID (Mike Heron)

Black Jack David is the name that I bear
been alone in the forest for a long time
But the time is coming when a lady I'll find
I will love her and hold her
singing through the green green trees

The skin on my hands is like the leather I ride
and my face is hard from the cold wind
But my heart so warm with the song that I sing
Will charm a fair lady
Singing through the green green trees

Fair Eloise rode out that day
From her fine fine home in the morning
In the flush of the dawn came a sound to her ear
Drifting and floating
Singing through the green green trees

Last night she slept on a fine feather bed
Far far from Black Jack David
But tonight she will sleep on the cold cold ground
And love him and hold him
Singing through the green green trees

Oh saddle me up my fine gray mare
Cried the lord of the house next morning
For the servants tell me my daughter's gone
With Black Jack David
Singing through the green green trees

And he rode all day and he rode all night
But he never did find his daughter
But he heard from afar come adrift on the wind
Two voices laughing
Singing through the green green trees

Oh Black Jack David is the name that I bear
Been alone in the forest for a long time
But now I have found me a lady so fair
I will love her and hold her
Singing through the green green trees

The theme of a young aristocratic lady running off with a gipsy seems to be a very old one, and while one can't deny the liking of some high born ladies "for a bit of rough" I wonder if it was really based on fact; would they really have swapped a life of luxury and ease to sleep on the "cold cold ground" (and live in poverty?). There is another variant on this theme "The Gipsy Rover" where the female runaway proudly boasts to her father, when he has caught up with her, that "He is no gipsy, father, but lord of these lands all over". At least in this case she knew which side her bread was buttered on.

As in some versions of the ballad the girl is only 15, legally this is basically a case of child abduction and if something similar happened today there would be an outcry about paedophilia, etc. In those times presumably people had a different attitude. I have just been reading that Henry VIII seduced Anne Boleyn's 14 year old sister Mary and then turned his attention to Anne (who was given tips on how to please Henry by Mary). The rest, as they say, is history.