Phil wrote:
"if I were to name (say) three songs Lloyd extensively rewrote and another two he more or less wrote from scratch, what kind of proportion of the songs he collected would those five represent?"

What you are asking for would take an awful lot of research (and NB Steve Winick's comments about Lloyd as collector). Steve's conclusions about Reynardine and The Recruited Collier represent a good deal more than an afternoon's work. Malcolm Douglas tells us on the 'Blackleg Miner' thread that he spent a year "attempting to deconstruct the songs in Lloyd's Penguin Book of English Folk Songs". So, someone would have to identify all the songs in Lloyd's publications and discography, then cross-refer them against all the published collections and broadside indexes.   But, as Steve has pointed out, his most significant influence was in passing songs on to important singers in the revival, so you'd have to talk to those people as well, and do the same kind of detective work on the songs they had from Bert.

I would love to have the time and funds to undertake that research myself (I thought about it seriously as a project at one time), but I'm a musician, and it's not gonna happen. Just out of idle curiosity, though, I spent a couple of hours yesterday with one of Lloyd's LPs – the excellent 'First Person' – and cross-referred some titles with the Roud Index available at VWML online [http://library.efdss.org]. I left out the Australian songs – others know more about those – and I should stress that I've only used a list of titles and sources, not the original manuscripts or books, so I can't compare the actual lyrics or tunes.

'Four Drunken Maidens': Lloyd tells us little about the provenance of this song other than that it "spread like wildfire" during the 18th century, and that "the tune we use is the standard one in the Southern counties".
Roud lists two versions, one in Baring-Gould's 'Songs of the West', and one in 'A Pedlar's Pack of Ballads and Songs' (Edinburgh, 1869). I couldn't find a match in the Bodleian Library's Broadside index.
This song has long been a folk club standard, which I guess is due to Lloyd's popularizing it - I'm not convinced it was as widespread as he suggests.

'Saint James' Hospital': As to his source, Lloyd reports only that the tune "was sung in Cork about 1790". I don't have the resources handy to check that, but Roud tells us that Hamish Henderson collected the song in Scotland in 1952, and Mudcatter Jim Carroll recorded a version from Tom Lenihan in Co. Clare in 1978. Harry Cox sang the song as well.

'I Wish my Love'. Attributed to the manuscripts of John Bell of Newcastle, where Lloyd tells us it is titled 'A Pitmans Love Song' - and that he fitted a tune himself. There are over three hundred items from John Bell's collection at the FARNE site [http://www.asaplive.com/FARNE/Home.cfm] but I haven't been able to find the broadside under this title – but then, I'm not sure whether the FARNE resource represents the whole of Bell's collection.

'Jack Orion'. Based on Child 67 'Glasgerion'. "I took it out and dusted it off a bit, and set a tune to it."
A pretty radical rewrite, actually, though none the worse for that.

'The Lover's Ghost' "The great Irish Collector Patrick W. Joyce learned this as a boy in Co. Limerick."
The title is listed in Roud under Joyce's 'Old Irish Folk Music & Songs' (1909), but I don't have a copy to cross-check. Looks sound, though.

'Short Jacket and White Trousers' "I can't find [this] in any of the English printed collections, but Firth of Pocklington (Yorks.) published a broadside of it…. A bit longer but perhaps not as good as our version here".
Roud has only one entry, 'Short Jacket and Blue Trousers', from Newfoundland, but if it's the same song this at least places it in oral tradition. I couldn't find the broadside version on the web.

'Sovay the Female Highwayman' "Every collector of prominence has found versions of it" – there are indeed a number of versions in Roud, several collected by Sharp and others from Kidson, Hammond and Gardiner. "The Dorian tune here is …. substantially the same as H. E. D. Hammond's tune from Long Burton, Dorset… I've added a pinch of spice to the rhythm." Hammond did indeed collect a version about 'Shilo' from a Mrs. Young of Long Burton, and Lloyd does indeed seem to have spiced up the rhythm.

'Farewell Nancy' "Substantially the one that Sharp noted from a 74-year-old Somerset woman with lovely tunes but an uncertain voice." There are several versions in Roud, but Sharp only collected one from a woman, this being Susan Williams of Haselbury Plucknett. Strange, then, to find that Sharp wrote that her voice was "sweet and pure as the note of the woodland thrush." Perhaps Lloyd confused her with another of Sharp's singers.

'Fanny Blair' "Sharp noted this extraordinarily handsome and elusive tune in Somerset", says Lloyd, who goes on to explain that the source singer jumbled the words and that Sharp himself collated a text. Lloyd also mentions that a version from a whaling ship's log specified Fanny's age as eleven, which ties in with Roud's entry for the song's inclusion in Huntington's 'Songs the Whalemen Sang'. Roud also lists a number of broadsides and several traditional versions from Southern England.

And that's it. It looks to me (again stressing that I haven't checked the named sources against the actual MSS) that most of these have sound traditional antecedents, even though some are clearly rarer in tradition than others. Only 'I Wish my Love' defied my attempts to locate a source, but that may mean no more than that FARNE didn't have access to the entire John Bell collection.

Of the rest, 'Jack Orion' is the kind of major Child Ballad reworking that a number of singers (myself included) have indulged in from time to time. 'I Wish My Love' uses an original tune, 'Sovay' a 'spiced up' tune, and some of the others may well have been collated. 'Short Jacket and White Trousers' is a rarity. At a guess, though, I don't think he wrote any of the songs "from scratch". His notes on the sources (he wrote a lot more than I've included here, in characteristically colourful style) are actually very full. So there – for what it's worth – you have it. If anyone has the time to check the sources more fully, please do.

'The Weary Whaling Grounds', however, thanks to the contributions of Curmudgeon and Lighter, we might now add to the list of 'Bertsongs'. And what a great job he made of it!

Finally, in answer to WLD's comment: "I think he was writing for young people who went to folk clubs rather than scholars. you see most people were young in those days."

I first read 'Folk Song in England' when I was seventeen. I was fascinated not just by the songs and the background information, but by Bert Lloyd's way with words. The fact that I now sing these songs for a living is due in part to his book.... and so too is the fact that I want to know where they came from.