I have always thought it to be a most improbable story but the tune is so good that I sing it now and then.

The version I have is from The Yetties and in it they "rode all night" and he was "taking of his donah".

Donah being a Cockney expression meaning girlfriend (or wife). I always wondered where Lamorna was. It would certainly be a long drive from London in a horse drawn cab, and would have taken several days.

Which brings up the question, Where is Albert Square? would it be in some west country city like Bristol. Or would that also be too far away?

I have always assumed that it was a music hall song that was written towards the end of the 19th. Century. Which would account for how the London slang could travel to Cornwall.