Verses 2-5 are very similar to "I'm a rover, seldom sober".

And the last verse reminds me of the only words I've ever found to the Morris tune Constant Billy:

Billy, Billy, [Oh/my] constant Billy
Oh When shall I see my Billy again?'
When the fish fly over the mountains
That's when you'll see your Billy again

Does anybody know any verse to Constant Billy?

WassaiL! V