And while we're at it, now that we're in the age of Google (which we weren't when the question was posed here), according to slangcity.com, re: "ball a jack" or "balling the jack" --

"... "balling the jack" has several meanings. None of them are used much these days, but maybe the expression may become more popular because of the recent novel, Balling the Jack, by Frank Baldwin. It's being made into a movie, starring Ben Affleck as a gambler, and the expression means "risking everything on one attempt" - in this case, he bets $40,000 on a dart game.

However, that's not the original meaning of the word. It was the name of a popular dance in 1913, which goes like this:

       [lyrics as above]

Later, the meaning was expanded from just "dancing" to "having a great time". Around the same time the song came out, the expression was used by railroad workers to mean "going at full speed." It's not clear whether the dance or railroad reference came first. And (if that's not enough) it's also been used to describe operating a jackhammer.

So it wasn't anything gross (disgusting), though you can find later uses of the expression where it has a sexual meaning, similar to "balling" (having sex). For example, in the 1940s, blues artist Big Bill Broonzy sang:

       My baby's coming home.
       I hope that she won't fail because I feel so good, I feel so good.
       You know I feel so good, feel like balling the jack.

Well, he could be talking about dancing... but maybe not."

~ B in T