Pitt's Mirskey Collection of Salon Orchestra and Silent Film Music is a large collection of printed music that was used in the early 20th century in various U.S. locales by Nek Mirskey's Polonia Orchestra. The collection includes a large amount of photoplay music, or music composed for the accompaniment of silent films. In 2023, the University Library System completed a project, funded by the National Endowment for the Humanities, to digitize the collection and make it freely available through ULS Digital Collections.

In the early days of the motion picture industry (until the late 1920s), the films themselves had no sound and were usually accompanied by live music performances. Performers could improvise or compose scores to accompany films, but in most movie theaters, scores were created by compiling short selections of pre-composed music which was often written specifically for that purpose- i.e., photoplay music. Theater orchestra conductors like Nek Mirskey had extensive libraries of photoplay music and worked hard to compile scores that would complement the on-screen action. 

In recent years, there has been a revival of interest in silent films and their accompanying music. Due to its size and to the evidence of practical usage in the form of annotations, manuscripts, and marginalia, the Mirskey Collection offers rare and valuable insight into the performance practices of this fascinating period.