] ]I seem to recall from somewhere (L&T?) that the contraction "an't" was viewed very much like today's "ain't": a sign of low breeding. And in S&S, I had always associated this word with the Steele sisters.

I cannot remember the source, but it has always been my understanding that the use of "ain't" or "an't" was at one time quite widespread and was not considered vulgar. It even became a fad among the upper classes to use the expression, and I believe the fad lasted until the latter part of the 19th century. I will see if I can locate my source.