When Andrew Earle Simpson arrived in Washington to become head of Catholic University of America’s Division of Theory and Composition, the music librarian, Maurice Saylor, soon introduced him to silent films. At the turn of the century, the stories on screen were propelled by theater pianists and organists who often chose classical excerpts to illustrate drama, comedy and suspense. Because many films were not scored, Simpson saw the need to compose appropriate music for them.

His latest accomplishment is an original score for “The Wind,” a classic silent film starring Lillian Gish presented Saturday at the American Film Institute. The world premiere commission from the Cantate Chamber Singers incorporates a chorus of 30 singers, an instrumental ensemble and Simpson at the organ.