On July 4, 1917, French actress Sarah Bernhardt speaks in Prospect Park, Brooklyn, N.Y., on behalf of French-American cooperation in the war effort. Addressing more than 50,000 people gathered around a decorated music platform, Mme. Bernhardt stands and speaks from an open touring car parked in front of the platform. Medium close shot of Mme. Bernhardt speaking and gesturing, with man who may be her personal physician, Dr. Felix Marot, and woman who is probably her secretary and translator, Miss...