Article: DT&I improves telephone communications - 1925

Radio communication along the DT&I ceased in early May with completion of a new and modern telephone and telegraph dispatching system between Detroit and Ironton. Transmission of commercial messages by radio has been in force on the DT&I for more than three years. It was installed as a means of expediting an increasing volume of business.

In addition, it has been used to speed up car tracing, and on a few occasions, as an emergency measure, radio served as a medium of assistance in dispatching trains. However, it has served the purpose for which it was installed; having provided a fairly reliable means of communication until the new wire system could be completed.

The DT&I is said to be the first railroad to employ radio as a means of transmitting daily routine business messages. The stations at Dearborn and Springfield have averaged 400 messages daily. Completion of the new telephone and telegraph dispatch system will provide continuous lines from Detroit to Ironton, a distance of approximately 396 miles.

Ten strands were laid between the Rouge and Flat Rock, and from six to eight extend from Flat Rock south. No. 9 hard-drawn copper wire was used exclusively, replacing the badly corroded iron wires which caused considerable trouble by breaking.

Both telegraph and telephone systems consist of two circuits, and a third telephone circuit is available by means of "pantomiming" wires of the other telephone circuits. The two telegraph circuits are "simplexed" to produce a station-to-station block telephone system. 

The perfected telephone dispatching system is faster than telegraph. Clear and direct communication may be had by dispatchers with every local station. [RSE-1925]