This collection of autographed inscriptions and letters from noted 19th century musicians was assembled by Mason. The material includes the signatures of 85 composer, performers, and other musical people, most of whom were Dr. Mason's contemporaries and personal friends. There are 103 items the majority of which are bits of music in script with signatures, and a few autograph letters to Mason. Among those represented are Berlioz, Jenny Lind, Franz Liszt, MacDowell, Paderewski, Rubinstein, Saint-Saens, Samaroff, and the Schumanns.