Mark finds a bridge (Mimi calls it 'Arch' form) structure (ABCBA) in Bartoks fourth string quartet. This I belive is one of Bartoks "tricks" of the trade, I first noticied it in his 'music for strings. Percussion and Celesta', and since in many other of his works, acctuly in many other composers works as well, the compositional trait ABC, turning backwards mid C and going BA ending up where You started has been used since the Renaissance. (some might complain that its not a perfect arch (like in the suggsted quartet), well; this is theoretical stuff, any prospering composer would as such, let the music grow around it..) cheers peter lundin