Horn Concerto no. 4 in E-flat major, K. 495

Mozart entered the fourth horn concerto in his catalogue on 26 June 1786, six weeks after the premiere of Le nozze di Figaro. It was written, like the others, for Joseph Leutgeb, and the surviving autograph is notated in four colours of ink — red, blue, green and black — one of the practical jokes that run through Mozart's dealings with him. The rondo finale is built on a hunting-call rhythm, the natural idiom of an instrument that had no valves; every note outside the harmonic series has to be found by the player's hand.