Hi Bill,

Vic has already given you most of what you wanted, but here are a few more details:

In The New Penguin Book of English Folk Song, which prints a version of 'The Cruel Ship's Carpenter' from Henry Burstow, collected in 1893, Steve Roud states that the song originated from a garland (i.e. songsheet) printed in England in the mid-eighteenth century, titled 'The Gosport Tragedy'. A shortened version was widely published as a broadside in the nineteenth century - here's one example:

Polly's Love

Most of the versions of the song collected in England follow closely the broadside text, which ends with Polly's ghost taking bloody revenge on her murderer. As late as 1958, a version - very full and again sticking closely to the broadside text - was recorded from Sam Larner, who called it 'The Ghost Ship' or 'The Ghost Song'.

It's worth mentioning that the broadside is one of the small family of 'Jonah Ballads' (also including 'The Ghost so Grim', 'Sir William Gower' and 'The Banks of Green Willow') in which a ship's voyage is disrupted by the presence on board of a miscreant, who must be disposed of before the vessel can sail ahead:

"There's a murderer on board, and he it lately has done
Our ship is in mourning and cannot sail on"

Vic is right to say that the American version as widely sung today lacks the ghostly ending. Here's a typical lyric: Pretty Polly; and great performance: Jeff Davis plays 'Pretty Polly'. It's often hardly recognizable as 'The Cruel Ship's Carpenter', except for tell-tale phrases like:

"He led her through woods and through valleys so deep,
Which caused this poor damsel to sigh and to weep"

... and the stark image:

"Your grave is now open and the spade is standing by"

However, when Cecil Sharp and Maud Karpeles went song hunting in the Appalachian mountains in 1916-18, they found several versions resembling the old British versions more closely. Two of the four printed with full texts in English Folk Songs from the Southern Applachians actually do finish with Polly's ghost claiming William, while another (from Jeff Stockton of Flag Pond, TN) includes in verse 1 the line "Him to his trade was ship's carpenter" (compare the English broadside), and a verse bringing out the 'Jonah' motif.

Looking through the 21 tunes printed in EFSSA (this was clearly a very popular song in the mountains!), it's interesting to see that the majority were in triple time - like the English song - with just a few having moved to the 2/2 or 4/4 time that characterises more modern American versions.

So you can actually find stages in the evolution of 'Pretty Polly' from its British origins (unlike many Appalachian ballads, the song' seems to have been more common in England than Scotland) to the familiar modern song, which has probably stablized in its present form as a result of recordings by singers like Dock Boggs and Ralph Stanley.