It's one of the best occupational songs, by the standard of productivity -- a couple of verses are pretty standard, but then there's a world of variation you never get to the end of. It's for somebody else to judge whether it's legitimate for somebody who's not a sailor, let alone a Black Baller, to compose additional verses. I believe "blow the man down" meant to lower the main sails ("mains'l" or "muns'l"), a complicated and potentially dangerous task requiring a lot of coopreation and coordination. But I don't know what kind of vessel we'd be talking about, or how many main sails it would have.

Best,

Adam