The "Folksinger's Wordbook", compiled by Fred and Irwin Silber, provides an additional verse, after "And being cruel still":

And being nigh to death, etc.
I vowed with every breath
To walk in wisdom's way, etc.

The last line curiously breaks with the rhyme scheme used throughout the rest of the song. I suspect it should be "path" (close enough for jazz).

The tune on the Golden Ring album (the only version I've heard) is the one Cecil Sharp gives for "Admiral Benbow" (No.87) in his "One Hundred English Folksongs". He says the air "Marrinys yn Tiger" is a variant of the same tune. He references a completely different version of Benbow, and a version with essentially the same words but a different tune.

The trial of Kidd and the engagement of Benbow with the French fleet occurred in roughly the same time frame (1702). I like to think there was a bit of irony in using the same tune for both a hero (albeit a minor one) and a pirate.

Actually, the facts we now have show quite clearly that Kidd was a pirate hunter and never a pirate. Most of his crew mutinied in order to turn pirate, and stranded him and the others on an island off Madagascar. Both William Moore and the gunner were leaders of the insurrectionists. In an argument on this issue, Kidd in exasperation tossed a bucket at Moore, which hit him on the head; Moore sustained a concussion and died of it the next day. Kidd was not the agent of the gunner's death, though I don't recall what became of him.   The trial was a mockery from beginning to end--the prosecution had in its possession the evidence proving Kidd's story, and prevented Kidd from using it in his defense. The very men who DID turn pirate gave perjured testimony in order to obtain pardons for themselves. The whole story is one of perfidy on all sides; read Zack's book "Pirate Hunter".

Kidd was orphaned very early in life, and was quite a devout man, so the entire song is a pack of lies. But it's great fun to sing.