I'd better post this here before it gets lost again (I lost it once before for several years).

From James Hall, "Letters from the West: Letter III," The Port Folio, XII (Sept., 1821), p. 446. Judge Hall made a trip down the Ohio from Pittsburgh to Shawneetown, Ill. This comes from a letter about Parkersburg, Virginia:

"To the admirers of the simplicity of Wordsworth, to those who prefer the naked effusions of the heart, to the meretricious ornaments of fancy, I present the following beautiful specimen verbatim, as it flowed from the lips of an Ohio boatman:

"It's oh! as I was a wal-king out,
One morning in July,
I met a maid, who ax'd my trade,—
Says I, 'I'll tell you presently,'
'Miss, I'll tell you presently!'"

Obviously the first stanza of a predecessor of the capstan shanty "New York Girls/ Can't You Dance the Polka?"

When Hall revised his article for book publication in 1828, he added a second stanza:

And it's oh! she was so neat a maid,
That her stockings and her shoes,
She toted in her lilly [sic] white hands
For to keep them from the dews, &c., &c.

So it isn't quite "New York Girls." And that unfortunately is that.

Except that Hall also quotes "the words which the rowers are even now sounding in my ears as they tug at the oar,

Some rows up, but we row down,
All the way to Shawnee town
Pull away - pull away!"

I believe Hall makes the earliest reference to the "Shawneetown" rowing song. Its form and the "pull away" chorus brings it very close to the apparently soon-to-evolve halliard shanties.