On January 25, 1915 the AT&T long-distance telegraph network, the development of which began in 1885, finally reached from New York to San Francisco, allowing Alexander Graham Bell in New York and Thomas Watson in San Francisco to participate in the first transcontinental telephone call. Photo by Irving Underhill.
"Four locations participated in the first call. Alexander Graham Bell, inventor of the telephone and co-founder of AT&T, led a group of dignitaries in New York. His one-time assistant Thomas Watson, led a group in San Francisco. AT&T President Theodore Vail [cousin of telegraphy inventor Alfred Vail] spoke from Jekyll Island, Ga. And U.S. President Woodrow Wilson spoke from the White House.
At one point during the call, someone asked Professor Bell if he would repeat the first words he ever said over the telephone. He obliged, picking up the phone and repeating 'Mr. Watson, come here, I want you.' To which Watson, in San Francisco, replied, 'It would take me a week now.' "(http://www.corp.att.com/history/nethistory/transcontinental.html, accessed 01-24-2010).