This poem seems another take on sailor fantasizing; see "Port o' Dreams" and "Sailor's Farewell." With C. Fox Smith the fantasy is often tempered with deeper insights.
"Peter" is a reference to the flag the sailors called "Blue Peter" which was flown to alert sailors ashore that their ship was about to leave port.
The original poem is quite similar to what Pint and Dale sing on their 2004 recording SEVEN SEAS, and the tune "Adieu Sweet Lovely Nancy" is a familar traditional one but not one I've ever tried to sort into chords.
This and 360 other poems by C. Fox Smith may be reviewed and harvested from the Oldpoetry website where Shanty Freak and myself have posted them: click here for website