The accuracy of longitude determinations by the U.S. Coast And Geodetic Survey by wire signals and general Ferrié's proposed radio longitude net

Almost from the beginning of telegraphy the U.S. Coast and Geodetic Survey determined differences of longitude by telegraph, and a network of lines between longitude stations has been spread over this country. An analysis of this work is opportune, as determinations of differences in longitude by wire signals will soon be superseded by work in which radio signals are used. It is important that the determinations by radio shall not be less accurate than the old work. In 1897 an adjustment of the longitude net was made in which 63 differences of longitude were used. The average correction to a difference was 0′019. There were 36 corrections less than 0.′02 and only two greater than 0′04. Since 1897 new determinations have been fitted into the adjusted net.