For the last (at present) reference that might be attributed to the 1850s, I want to copy (with minor additions) John Minear's post from elsewhere on Mudcat.

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Posted By: John Minear
31-Mar-10 - 07:45 AM
Thread Name: From SF to Sydney - 1853 Shanties Sung?
Subject: RE: From SF to Sydney - 1853 Shanties Sung?

Here is a reference to the hauling/halyard chanty "Whiskey for Johnny!" being used to "pull round the yards" on board of the packet ship "Mary Bradford" on a cruise from London to New York, from the book THE REAL EXPERIENCES OF AN EMIGRANT [(Ward, Lock and Tyler)]:

       "The passengers assisted the sailors to pull round the yards - a work of great difficulty. It was done by a series of pulls - thus: one man took hold of the rope and stood on the spar of the bulwark, singing a few words of a song - I could not make them out - the others called out, "Whisky for Johnny!" and gave a simultaneous haul, when the yard came round an inch or two, and so they continued until the sail was sheeted home." (p. 39)

The frustrating thing about this reference is that there is no publication date that I can find for the book other than "187?". And like a lot of these accounts, the writer chooses to *not* give a date for his experience! I have yet to understand this, unless it is a way of covering up a fiction. It makes me suspicious right off. He says, "On Saturday, the --day of June, 18--, I embarked on board the "Mary Bradford," then lying in the basin of the London Docks, and bound for New York." (p. 5)

There certainly was a "Mary Bradford", and she was one of the "Swallow-Tail Line of Packet Ship", sailing every alternate Thursday from New York and London. Here is an advertisement from 1859:...

She was launched in October of 1854 at Warren, Rhode Island, and immediately sailed for Mobile....

And on July 5, 1855, she was struck by lightning at Battery Wharf in Boston!...

While it is a somewhat shaky guess, I would say that this reference to "Whiskey for Johnny!" *could* be located in the later 1850s. It seems to place it in the packet trade. However, this chanty has quite a reputation for being used on board the packet ships. It is strange that this is the only reference I have been able to find that really confirms that, so far. All of the other solid references to "Whiskey Johnny" are later.
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As far as dating the event goes, that makes a lot of sense to me. Additionally, the narrator mentions meeting a survivor of the U.S. steamship CENTRAL AMERICA, which used to transport gold-seekers between NY and Panama, and which sank off North Carolina in Sept. 1857. Abolitionists are mentioned, but the Civil War is conspicuously absent. So between 1858-1860 sounds about right. OK?

My suspicion is that this is not the halyard chantey "Whiskey for Johnny." Because if they were pulling the yards around (tacking), they'd be hauling on braces, right? (Someone please adjust my shaky sailing knowledge.) It sounds like a sheet shnty or a "sing-out," where perhaps there was just a hard pull on "Johnny!" Thoughts?