If you've never ventured downtown to experience the Organ Loft's silent film series, you've got an opportunity tonight to sample the experience in the South Valley. --- The fall series of bi-weekly silent films at The Organ Loft begins this week with Douglas Fairbanks in 1920's The Mark of Zorro on Thursday and Friday -- but that won't be the week's first offering of silent cinema. Sandy Amphitheatre (1245 E. 9400 South) will host a free program tonight (Sept. 5) of classic silent shorts featuring Laurel & Hardy, Charlie Chaplin and Buster Keaton. The Organ Loft's regular accompanist, Blaine Gale, will play the organ during the films. The films begin at dusk (approximately 8:30 p.m.), and the amphitheatre includes both fixed seats and lawn seating. Bring a blanket, bring the family and take a journey back in time.