Franz Xaver Hauser (1794-1870), born near Prague in Czechoslovakia, combined his career of singing and teaching with a consuming interest in the music of Johann Sebastian Bach. Hauser was a colleague of Felix Mendelssohn, Moritz Hauptmann, Robert Schumann, Jenny Lind, and Otto Jahn; author of a text on vocal pedagogy that stayed in print for more than a century; founder of the Munich Tonal Academy, which is still in existence; and the primary...