On Tuesday nights in the North Seattle neighborhood of Wedgwood the backroom of the Wedgwood Alehouse is taken over by an Old Time jam. Instrument cases pile up under the pool tables, chairs and stools are brought into tight concentric rings, a melody will be offered up from a fiddle somewhere in the corner, and then the room is off and running. If you know the tune, you play it. If you don't, you learn it as you go. In between tunes, drinks are drunk, gab happens, and th