© Edwin Clarence Hedler; title, descr., & small roll, 15Jan40; MU9949.

THE PRIMARY CELL; electricity from chemical action. Encyclopaedia Britannica Films, Inc., c1944. 1 reel.

© Encyclopaedia Britannica Films, Inc.; 2Jun44; MP15910.

THE PRIMARY CELL. SEE

La Pila Simple.

A Pilha Elétrica.

PRIMARY FLIGHT TRAINING, STAGE A. sd. United States Navy, Bureau of Aeronautics Training Division.

© The Jam Handy Organization, Inc.; title & descr., 8Jul43; 87 prints, 5Jul43; MU13998.

PRIMARY FLIGHT TRAINING, STAGE B. sd. United States Navy, Bureau of Aeronautics Training Division.

© The Jam Handy Organization, Inc.; title & descr., 8Jul43; 84 prints, 5Jul43; MU13999.