In the old walkaway song/sea shanty known as "A Drop of Nelson's Blood," "Roll the Old Chariot," or "Roll the Old Chariot Along," the last line of each stanza is, "And we'll all hang on behind" (some versions say, "And we won't hang on behind" instead).
What is the meaning of "hang on behind" in this context?
I was fortunate enough to talk to a tallship sailing captain, and "hanging on" (or as a noun, being a "hanger-on") refers to when one sailor hauls on a line with a too-heavy load, so multiple other sailors help out by "hanging on" to the rope to add their weight and strength.
Ergo, the lyric, "we'll all hang on behind," likely means something similar to, "we'll all help each other / be in it together."
Many explanations of the origins of the song, here are some :
speak of it as being a re-arrangement of a song from the Gospel tradition called "Roll the old chariot", with "Hanging on behind" suggesting people following on behind the chariot as it rolls. That idea also works in the shanty version, suggesting the sailors tagging along behind whatever pleasures of the flesh the verse describes, and would give the singers something to act out. As first-language speaker of English, I don't believe "hanging on behind" has any other special meaning to sailors.
