| Description | The impending change of frequency and voltage in the Birmingham area. Dgms. 43pp. 1931. MANN (FRANK HARRIS).
Some experiences in air survey work. 9pp. Illus. Dgms. 1931. COCHRAN-PATRICK (CHARLES KENNEDY).
President's address. 13pp. 1931. SMITH (ARTHUR ERIC) B.Sc..
The transmission of power by ropes. Illus. Charts. 18pp. 1931. LEIGH (JOHN). |