All right, let's get this out of the way straight off. I hear those of you who know me well giggling in the corners. "Nice excuse to post a picture of a half-naked Russell Crowe, Pauline!" Fine. Maybe it is. Looks better than the ridiculous picture of a jackrabbit that I found on Google Images, doesn't it, ladies? Ah hell yeah. Besides, that's not Russell Crowe, that's Captain John "Jack" Aubrey, RN. See how it all ties together?
From the 17th century on, Jack was the common term for a sailor in England and her colonies. In French, the name was Jacques. This is interesting because in English "Jack" is a diminutive of John, whereas in French - particularly the Creole French spoken in the Caribbean and Louisiana - "Jacques" is a diminutive of James. Go figure.
Anyway, the name Jack began to be applied to things that had to do with sailors and shipping. There were black jack tankards for swilling grog, jack-blocks for tying off topgallant sails, jack cross-trees made of iron to support high sails like royals, jack-in-office, a common sailors' term for a snarky officer and foremast jack, the common sailor just spoken of who worked "before the mast" rather than aft on the quarterdeck. The name Jack became so attached to Englishmen around the world that the flag of Britain, with its confluence of St. George's, St. Andrew's and after 1801 St. Patrick's crosses, became known as the Union Jack and was first flown on Royal Navy vessels. Huzzah!
Still in parlance today is the word "John" for a prostitute's customer. "Jack" was the original term used by "doxies" (girls who worked the dock) for any paying sailor. Prostitution was tacitly sanctioned by most navies and, when ships were at anchor near home, "bum boats" were rowed out with provisions and paid companions for the sailors rather than allowing shore leave. This was particularly necessary in the Royal Navy where impressed men might take the opportunity to escape.
Also, there's the word "jacket" for a short, sturdy coat. Before foremast jacks were issued uniforms these types of all purpose coats were made by the men themselves out of sail cloth or nankeen and they easily identified a man as a Jack - a sailor who was not an officer, surgeon or member of the clergy. In French a jacket is now a veste but during the Napoleonic era it was a jaquet - a nod to not only French sailors but Revolutionaries who were known as Jacques as well.
So there you go. If you run into a man named John today, Brethren, call him Jack. Or if he's James, call him Jacques. Why the hell not? Happy Saturday to you, and three cheers for Lucky Jack!