![]() Since its beginnings in 1877, the long-term goal of The Bell Telephone Company was to create a network that would connect all parts of the U.S. with voice communication. Although the company began using the logo pictured in 1885, the service available was strictly local. The problem was the technology. The telephone Bell had patented in 1876 created a weak signal that quickly faded as the distance between callers increased. Bell Company's engineers like Edison's inventions depended on trial and error. Thomas Edison, perhaps the greatest American technological innovator tried 6000 different materials before finding the best filament for his electric light and in his efforts to improve the quality of voice transmission he tried lead, copper, manganese, graphite, osmium, ruthenium, silicon, boron, iridium, and many other substances before stumbling on carbon granules. ![]() The trial and error quest for greater distance made it possible for Bell engineers to eventually extend the long in long distance to mean 1700 miles, still about 1000 miles less than would be needed for a New York to San Francisco call. Trial and error discovered that signals traveled farther: if thick copper wire was used; if "loading coils" were added about every 6000 feet along the wire; and by employing electro-mechanical repeaters, which were simply telephones reconfigured by connecting speakers (the earpiece) to the microphone (the mouthpiece). Unfortunately, the repeater also distorted the signal so that only a maximum of two could be used on any circuit. Despite nearly three decades of work, telephone technology in 1907 was not significantly better than the technology Bell had patented in 1876. By 1904 trial and error hit a wall. A new approach to technological innovation at AT&T-Bell Telephone began in 1904 with the hiring of Frank B. Jewett in the transmission engineering department. In addition to the usual credentials the company sought in its engineers, ingenuity and mechanical skills, Jewett added a new capability; he was a trained physicist, having studied with the University of Chicago's Robert A. Millikan. The University of Chicago, abundantly funded by John D. Rockefeller, was one of the several American universities like Johns Hopkins and Cornell that were modeled on German universities that emphasized basic scientific research. As a student Jewett had assisted Millikan in the conduct of his famous "oil drop" experiment would prove the existence of the electron and which would also earn Millikan a Nobel Prize in 1923. ![]() In 1909 a new company president gave Jewett, now a manager, the task of making a coast to coast call a reality. The deadline for the task was 1915 where a truly long distance call could be shown at the Panama-Pacific International Exhibition in San Francisco. For Jewett the solution began with basic physics. Instead of going to his engineering department Jewett paid a visit to his physics teacher Robert Millikan and asked him to recommend several of Millikan's best physics students. Jewett's strategy mirrored something already tested and proven successful in Germany; an investment in basic scientific research created the foundation for new technologies such as in Germany's world-leading chemical and steel industries which were the world's most advanced because of the basic scientific research conducted in German universities. By 1915, the University of Chicago physicists working in Jewett's department had discovered the work of another Ph.D. physicist, Lee DeForest, a Yale Ph.D. who had studied with Williard Gibbs. De Forest had invented a vacuum tube, the audion based on De Forest's work on radio waves. The audion was an amplifier. Its work was done by generating electrons on a hot filament (a cathode), the electrons pass through a metal grid, attracted by a cool metal plate (an anode). It was found that adding current to the cathode amplified the small signal so that it could travel farther without distortion. Jewett’s young scientists successfully adapted the audion to Bell’s task by 1915. In a widely advertised phone call in which the now elderly and retired Alexander Graham Bell in Boston, called both President Woodrow Wilson in Washington, DC, and Thomas Watson, Bell’s old assistant in San Francisco at the site of the Panama-Pacific International Exposition. During the call Bell repeated his famous first telephone call, ‘Mr. Watson, come here I need you.” Ten years later, the laboratory that Jewett had created to solve the distance problem was formalized into an entire division within AT&T that was staffed by 4,000 scientists and engineers. The new Bell Laboratory was led by Frank B. Jewett until 1940, with Jewett becoming the president of its board of directors. From 1925 until 1984, Bell Laboratory was arguably the most productive research center in the U.S. Among its world changing innovations was the transistor. How it was invented was typical of how science and technology worked together. Bell Lab’s John Bardeen, a theoretical physicist and his office mate Walter Brattain, a bench physicist who built the devices that Bardeen used to test his theories, a collaboration that resulted in the transistor. In addition to the transistor data networking, the solar cell, cellular telephone technology, the laser, communications satellites, the Unix Operating System and C Language, Digital Signal Processing, and evidence of the Big Bang were all produced at the Bell Laboratory. Note: Bell patented his telephone in 1876. In 1877 Bell Telephone Company was founded, followed by other branches. One of these American Telephone & Telegraph became the parent company in 1885. Resources: Bell Laboratory Accomplishments Gertner, Jon (2012). The Idea Factory: Bell Labs and the Great Age of American Innovation. Penguin Books. New York. DeForest, Lee (1907). The Audion.—I.: A New Receiver for Wireless Telegraphy. Scientific American Supplement No. 1665, November 30, 1907. DeForest’s account about the audion tube. The account shows how scientific observation and experimentation lead to technological innovation. Millikan’s “oil drop” experiment was done to determine the charge of an electron. Millikan constructed an apparatus composed of two metal plates in an enclosure. Electrically charged oil drops were sprayed into the enclosure and were held in balance between the plates. Alternating the charge in the plates would allow the droplets to fall at a constant rate, the gravitational and the electrical forces were equal. Frank Jewett spent many hours at the enclosure watching oil droplets as they fell. Images: The Bell Long Distance Logo, p. 1 Bell Telephone Company Repeater diagram, p. 2 DeForest Audion Tube, p. 3
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Dr. John HOlton
Dr. John Holton joined the S²TEM Centers SC in July of 2013, as a research associate with an emphasis on the STEM literature including state and local STEM plans from around the nation. Archives
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