Hanson, Howard. (1896-1981) Autograph Manuscript, "Harmonic Materials of Modern Music."A fascinating autograph manuscript, 37 handwritten pages, including revisions and corrections to his "Harmonic Materials of Modern Music: Resources of the Tempered Scale" (New York, 1960), described in Grove as "a seminal work in what would later be termed pitch class set theory." The manuscript consists of numerous charts, lists of pitches and formulas of various kinds, completed mostly in pencil, with a few leaves in ink. Hanson apparently intended