As a war measure, on July 31, 1918, by executive order issued in accordance with a Joint Resolution of the House and Senate, the telegraph and telephone systems of the United States were placed under the control of the postmaster-general, and on November 2, 1918, the marine cables were also placed under his control. These utilities were conducted by a wire control board, of which the postmaster-general was the head. The marine cables were returned to their owners May 2, 1919, and the telephone and telegraph lines were returned to their owners in accordance with an act of Congress on August 1, 1919, having been under government control just one year. When the telegraph was invented, in 1847, the first line between Washington and Baltimore was built through an appropriation authorized by Congress. Then, as now, there were public men who advocated government ownership of the wire systems as a means of communication, the same as the postal service. It was placed in private control, however, one year after its inauguration, and has grown up under that control. The Government's operation during the war of both the wire and railroad systems seems to have cooled the ardor of even the most enthusiastic advocates of government ownership of such utilities. Early in 1919 the Post-office Department used the wireless telegraph in connection with air mail service. A central station is located in the Post-office Department Building at Washington, and other stations are located in cities near the transcontinental air mail route from New York City to San Francisco. Experiments are being made with the wireless as a means of directing airplanes in flight, especially during foggy and stormy weather, and it is expected planes will ultimately be equipped with either wireless telegraph or telephone outfits. On April 22, 1921, the Post-office Department adopted the use of the wireless telephone in addition to the wireless telegraph service, and is now using both in the air mail service, and also for the purpose of broadcasting to farming communities governmental information such as market reports from the Agricultural Department and the big market centers. It is not contemplated, however, that the Post-office Department will maintain the wireless telegraph and telephone except as an aid in the development of the air mail service; only when not in use for this purpose is it utilized to broadcast the governmental information referred to for the benefit of farming communities and without expense to them. _The Post-office in the War_