The President of the United States of America, authorized by Act of Congress, July 9, 1918, takes pleasure in presenting the Army Distinguished Service Medal to Lieutenant Colonel Augustus Trowbridge, United States Army, for exceptionally meritorious and distinguished services to the Government of the United States, in a duty of great responsibility during World War I. As Supervisor of the technique of flash and sound ranging, by his complete scientific knowledge and keen devotion to his important duties Lieutenant Colonel Trowbridge rendered services of great value. Due to his good judgment and painstaking energy suitable personnel were selected and properly trained in the efficient operation of the Flash and Sound Ranging Service of the American Expeditionary Forces.