I'm trying to remember a folk song I heard (recorded, sung by a man with a guitar) as a child. The only part I can remember now is from the refrain, which goes
Singing Jimmy, dearest Jimmy,
On the banks of the deep blue sea,
Are you going to leave me here alone
And forsake your own country?
Only I'm not sure about the name (Jimmy? Polly?), or what exactly they're on the banks of (maybe it was Loch Dundee, although the sea seems to make the most sense in context). It also might have been "forget" and/or "your own Polly" at the end. I hope this is enough to go on! I do remember the tune, so I can try to figure out how to attach a sound clip.
More info in response to comments: I have tried googling pretty much every variation of these lyrics, but so many of the words and themes (leaving a lover, the deep blue sea) are common that I haven't turned up anything. (Most of the results are lists of songs, where these words show up scattered across many titles, so there aren't any clear candidates I can say "it's not that.") If I use quotes I get no results.
It's probably American or Canadian, although there's a specific record I would have heard it on if it were Canadian and I can't find it on there.