In the early part of the war I became interested in fragments of the works of Johann Sebastian Bach quoted in books on the theory or history of music, or in albums of pieces, printed during his lifetime or in the fifty years from his death to the appearance of the first collected editions. In Marpurg's Abhandlung von der Fuge (1753, 1754), I found unexpected treasure; not only were there many quotations from a wide range of Bach's compositions, showing clearly that Marpurg was acquainted with the whole of Bach's output, but I found the subject and answer of a tonal fugue unknown to the complete edition of the Bach-Gesellschaft.