Many years ago, I saw a movie about the navy and the second world war.
The movie starred James Cagney. It had a theme song that stuck in my mind - but unfortunately only the first verse did. It went like this:

"I knew a boy who went to sea
And he left the shore behind him
I knew him well for he was me
And now I cannot find him"

It may have been written for the movie but it had a lovely melody that sounded vaguely irish. Would appreciate the complete lyrics.