Printing telegraph systems applied to message traffic handling

R. E. Chetwood: At the present time, in the Western Union System, we have about 185,000 miles of trunk wires, equipped with automatic, printing telegraph apparatus. If the automatic apparatus had not been used it would have required approximately 460,000 miles of wire to handle the same amount of traffic. That shows a great saving in wire plant, due to the use of automatic apparatus. Another figure that possibly would be of interest is that today approximately 75 per cent of the trunk line traffic is handled by automatic apparatus. By automatic apparatus, I refer to apparatus of the type described in the paper and also the heavy traffic apparatus which was described in Mr. Bell´s paper of two years ago.