 Liszt also published a series of writings titled "Baccalaureus letters", ending in 1841.During the Weimar years, Liszt wrote a series of essays about operas, leading from Gluck to Wagner.Liszt also wrote essays about Berlioz and the symphony "Harold in Italy", Robert and Clara Schumann, John Field's nocturnes, songs of Robert Franz, a planned Goethe foundation at Weimar, and other subjects.