Telegraphing by Typewriter 



How one telegraph company doubled its 

 facilities without adding a single wire 



TO provide adequately for the handling 

 of its enormously increased business, 

 the Western Union Telegraph Com- 

 pany was recent- 

 ly confronted with 

 the problem of 

 doubling its serv- 

 ice facilities. To 

 double the number 

 of telegraph lines, 

 and therefore, to 

 increase the num- 

 ber of employees, 

 was too costly for 

 serious considera- 

 tion. Automatic 

 telegraph oper- 

 ators were in- 

 stalled. Their 

 speed is so great 

 that more than 

 twice the number of telegrams formerly 

 handled can now be sent over the same 

 lines. 



This is how it was made possible. Typists 

 take the place of key operators. As they 

 operate special typewriters, they perforate 

 a narrow strip of paper with a number of 

 holes, the arrangement of which varies with 

 each letter of the alphabet. A strip of paper 

 is to the new system of telegraphy what the 

 music roll is to the player-piano. As a given 

 perforation in the music roll determines 

 the note to be played, so a tape perfora- 

 tion determines the 

 letter to be printed 

 at the receiving sta- 

 tion. A tape is type- 

 written and drawn 

 through the electric 

 transmitters© quick- 

 ly that one thou- 

 sand, six hundred 

 and fifty words can 

 be sent in the time 

 required by one typ- 

 ist to send a thou- 

 sand words with the 

 regular key. 



Thus the company 

 has increased the 

 amount of business 

 it handles by sixty- 



The device by means of which four 

 messages come and four go over 

 the same wire at the same time 



Typists operate special machines which 

 make records of the messages in perfor- 

 ations on paper like player-piano records 



756 



five percent, without the addition of a single 

 new line ! It did not stop at that, however. 

 Key operators can work "quadruplex" — 

 that is, four of 

 them -can send 

 their messages 

 over a single wire, 

 two in one direc- 

 tion and two in the 

 other direction at 

 the same time. 

 The typewriters 

 were made to do 

 the same. We thus 

 come to the second 

 improvement, a 

 device which al- 

 lows four messages 

 to be transmitted 

 from the sending 

 to the receiving 

 station and four in the opposite direction 

 from the receiving to the sending station 

 at the same time and over the same wire ! 

 Two brushes, one at each station, rotate 

 over four segments at the same speed and 

 come in contact with corresponding seg- 

 ments at all times. At one station, the 

 four segments connect with the four tape 

 transmitters; at the other, they connect 

 with the four printing machines. While 

 one transmitter is sending a letter to its 

 corresponding printer, the brushes will be 

 moving toward the next segment. The 

 printer levers will 

 select the letter and 

 will print it on the 

 regular telegram 

 blank while the 

 brushes are rotating 

 over the three re- 

 maining segments. 

 The first printing set 

 is then ready for the 

 next letter. This 

 happens with every 

 segment, so that 

 with each complete 

 revolution of the 

 brushes, one letter 

 will have been sent 

 and received by four 

 operators. 



