It is a genuine Tom Lewis verse, Leadfingers. I tried posting earlier but the post rejected. Here goes again...

"Now Bold Sir Walter Raleigh was a sea-dog brave and true
He sailed the Indies, fought the Spaniards, found tobacco too
He laid his cloak down in the mud, so Bess took him to bed
But in the Tower Of London he completely lost his head"

FYI, it IS actually included in Tom Lewis' Songbook - in a fulsome footnote to the song (page 47), Tom says therein that he only remembered writing it after hearing it performed by The Anchormen on BBC radio one day - he'd completely forgotten it, and "never included it in (his) version after its first few outings", but he generously adds: "please feel free to use it, if you will".

Interesting that you've heard it recently GRex - I thought I was the only one singing it (except for Keith and Ian of course)!