TO SEPT. 3

Image-bearing celluloid preserves lost worlds but is itself extraordinarily vulnerable. The battle to save the world’s cinematic heritage is ongoing, fought by such institutions as the Library of Congress, the Museum of Modern Art, the George Eastman House, and the UCLA Film and Television Archive. Those are among the organizations that preserved this series’ titles, which range from foreign art films to American B-grade pictures. The scope is demonstrated by this weekend’s offerings: “A Slapsticon: Silent Film Comedy, 1916–1929” (at 4 p.m. Saturday, July 30) collects shorts starring Stan Laurel (without Hardy), Charley Chase, and Billy Whiskers, billed as America’s only goat comedian; it’s followed by The River (at 4:30 p.m. Sunday, July 31), Jean Renoir’s lovely vision of life along the Ganges in West Bengal. Filmed nearby a few years later, Pather Panchali (at 2:30 p.m. Saturday, Aug. 6) introduced Western audiences to Satyajit Ray’s world—as well as Indian classical music, via Ravi Shankar’s score. The program’s other rural idyll is Zem Spieva (at 2:30 p.m. Saturday, Sept. 3), an overview of Slovakian folk culture. There’s also plenty of mainstream fare, including The Man From Planet X (at 4:30 p.m. Sunday, Aug. 7), an alien-invasion cheapie by Edgar G. Ulmer, a Viennese aesthete who took to Hollywood like a duck to duck chow. (It’s shown with a new documentary about the director.) Also included are films by Alfred Hitchcock (Suspicion, at 2:30 p.m. Saturday, Aug. 13, is pictured), David Lean, George Cukor, and a young Frank Capra. The series runs through Saturday, Sept. 3, in the National Gallery of Art’s East Building Auditorium, 4th Street and Constitution Ave. NW. Free. (202) 842-6799. (Mark Jenkins)