- Historic Sites
Breaking The Connection
The story of AT&T from its origins in Bell’s first local call to last year’s divestiture. Hail and good-bye.
June/july 1985 | Volume 36, Issue 4
The growth of the system would not have been possible without constant technological innovation. One early problem was the proliferation of telephone poles and overhead wires, vulnerable to violent weather. The solution was the development of dry-core leadsheath cables that made underground wires practical. Another problem was static caused by electric light and electric trolley systems as well as by natural electricity. The solution was to replace one-wire circuits that used the earth itself as a conductor with two-wire circuits insulated from the earth. That meant rewiring the entire system, and that was exactly what was done, between 1890 and 1900.
As volume increased, the reliance on manual switching of calls became a matter of considerable concern. The larger the number of subscribers, the greater the cost of serving each one. One early manager commented that so far as he could see, all he had to do was to get enough subscribers and the company would go broke. This time the solution came from a source outside the Bell System—a Kansas City undertaker, Almon B. Strowger, who in 1891 invented an automatic switchboard that initially could handle ninety-nine telephones and soon was improved so that it could handle more.
The technological problems associated with the development of longdistance telephony were enormous. One major advance occurred in 1900, when Professor Michael I. Pupin, of Columbia University, showed that loading coils placed at frequent intervals in a telephone circuit would improve transmission. Before 1900, one-quarter of all capital invested in the telephone system had been spent on copper for wires; in addition to improving transmission, the Pupin coil cut in half the diameter of the wire needed for long-distance lines and thus cut those costs in half.
By 1925 AT&T’s stations served 60 percent of all radio owners.
The Pupin coil reduced attenuation, but it did not amplify sound. A threeelement vacuum tube, or Audion, invented by Dr. Lee De Forest in 1906-07 provided the basis for solving this problem. De Forest was an independent inventor, not employed by Bell. Building on his work, a young engineer at AT&T, H. D. Arnold, developed a high-volume vacuum tube that could be used in telephone repeaters to amplify sound.
Together the Pupin coil and the vacuum tube repeater made possible the first transcontinental telephone line. The last pole went up at Wendover, Utah, on the Nevada-Utah state line, on June 17, 1914, and a successful test was conducted at the end of July. On January 25, 1915, thirty-nine years after the first telephone conversation, the transcontinental line was formally opened, with Alexander Graham Bell, now sixty-seven, at one end in New York, and Thomas A. Watson, now sixty, at the other end in San Francisco.
A new technology, radiotelephony, made quick strides in this period. In 1907 Lee De Forest had transmitted voice without wires between two buildings in New York City. By 1909 researchers at AT&T were following his lead. Their work led to the first transatlantic radiotelephone transmission on October 21,1915, when a Bell engineer at the Eiffel Tower in Paris heard a few words addressed to him by an engineer in Arlington, Virginia. In the Bell tradition of uninspired messages on great occasions, the first words to wing across the Atlantic were “Hello, Shreeve! Hello, Shreeve! … And now, Shreeve, good night.”
The twenties were dizzy years for AT&T, with the company deeply involved in pioneer work in the new communications media: radio, television, and sound motion pictures.
Much attention was devoted to the development of regular transatlantic telephone service by radio. After a test in 1926, commercial service between New York and London opened on January 7, 1927. By the end of 1929 service had been extended to most of the major cities in Europe, as well as to Spanish Morocco.
Radio offered possibilities that went far beyond telephony, and AT&T was eager to explore them. On July 25,1922, the company launched a pioneer radio station, WBAY (later WEAF), which broadcast from the Long Lines Building on Walker Street in New York. Bell’s network of telephone wires enabled it to establish the first radio network, which in June of 1923 carried the first nationwide radio address by an American President (Warren G. Harding on “The World Court”). Within two-and-a-half years, a national network of seventeen stations owned or licensed by AT&T served more than 60 percent of all radio sets in the United States.