Kidding on the square

Posted by John on November 08, 2009 at 11:11

"Kidding on the square"? I know what it is supposed to mean. I worked that out from the context. But does anyone know where it comes from? So far as I can find, only the writer, Mr. Turtledove uses it. I know, that would make it *un*common, but this bugs me enough to ask on the off-chance someone has a clue. Thanks.