Thanks so much for posting the lyrics, thoroughly delightful! I've done a desultory troll about online looking for an author to this song, and thus far come up empty; quelle dommage, as it really is terrific.
We just love this sort of stuff in my family. My mother was raised in England by her grandparents during WWII, and acquired a great many tunes from her grand-dad, who had done some music-hall as a young man, and we were raised on it as children. Everyone seems to go back to Peter Sellers for this one, but he had to have got it from somewhere, no? The Mudcat is invariably the best place to come with these sorts of questions, as they are almost always solved (even if it takes some time), so I'm confident we'll get to the bottom of it yet.
And Murray--I'm with you: this whole business of Google slashing and burning its way through YouTube is the height of foolishness, especially for the interests of the artists shown there. Anyone seeing the clip of Norma Waterson singing 'Black Muddy River,' for instance, would go looking for more.