lessons. In 1819, Zelter was appointed as the composition teacher of Felix and his sister Fanny; he taught counterpoint and music theory according to the methods of Kirnberger. Felix's piano teacher was Ludwig Berger, a pupil of Muzio Clementi, and his organ teacher was August Wilhelm Bach (unrelated to J.S. Bach), who had himself studied musical theory under Zelter. A.W. Bach was organist of the Marienkirche, Berlin, which had an organ built in 1723 by Joachim Wagner. Mendelssohn's organ lessons were conducted on the Wagner organ, with Fanny present; they commenced in 1820 and lasted for less than two years. It is probable that he learnt some of J. S. Bach's organ works, which had remained in the repertoire of many Berlin organists; his choice would have been limited, because at that stage his pedal technique was still rudimentary. In autumn 1821 the twelve-year-old Mendelssohn accompanied Zelter on a trip to Weimar, stopping on the way in Leipzig where they were shown the cantor's room in the choir school of the Thomaskirche by Bach's successor Schicht. They stayed two weeks in Weimar with Goethe, to whom Mendelssohn played extensively on the piano each day. All Mendelssohn's music lessons stopped by summer 1822 when his family left for Switzerland. In the 1820s, Mendelssohn visited Goethe four more times in Weimar, the last time being in 1830, a year after his resounding success in reviving Bach's St Matthew Passion in Berlin, with the collaboration of Zelter and members of the Sing-Akademie. On this last trip, again by way of Leipzig, he stayed two weeks in Weimar and had daily meetings with Goethe, by then in his eighties. He later gave an account to Zelter of a visit to the church of St Peter and St Paul where Bach's cousin Johann Gottfried Walther had been organist and where his two eldest sons had been baptized: In 1835, Mendelssohn was appointed director of the Gewandhaus Orchester in Leipzig, a post he held until his death in 1847 at the age of 38. He soon met other Bach enthusiasts including Robert Schumann, one year his junior, who had moved to Leipzig in 1830. Having been taught piano by J.G. Kuntsch, organist at the Marienkirche in Zwickau, Schumann seems to have started developing a deeper interest in Bach's organ music in 1832. In his diary he recorded sightreading the six organ fugues BWV 543–548 for four