File:Bell telephone magazine (1922) (14776667493).jpg

Identifier: belltelephonemag26amerrich (find matches)
Title: Bell telephone magazine
Year: 1922 (1920s)
Authors: American Telephone and Telegraph Company American Telephone and Telegraph Company. Information Dept
Subjects: Telephone
Publisher: (New York, American Telephone and Telegraph Co., etc.)
Contributing Library: Prelinger Library
Digitizing Sponsor: Internet Archive

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Part of the testin? laboratory at I2J Purchase Streetin T889 In August, 1904, the first commer-cial application of the Shreeve re-peater was made at Pittsburgh on anopen-wire circuit between Chicagoand New York. Substantial improve-ments were made in this repeater inthe years that followed, and it wasused in the Bell System to a limited The Shreeve repeater was of the extent until superseded by the vacuummechanical type, in which the work- tube repeater,ing parts of a telephone receiver andtransmitter were combined in one in-strument. By careful refinements indesign, Shreeve was able to so reducethe inertia of the working parts thathe succeeded where others had failed. It was not until Arnolds improve-ment of the deForest audion, whichled to the high-vacuum electronictube in 1913, that a satisfactoryvacuum-tube repeater became avail-able. This was not due to a failure 166 Bell Telephone Magazine AUTUMN
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A corner of the Mechanical Department laboratory at 12/ Purchase Street about i8go to recognize the possibilities of elec-tronic amplification or to lack of ef-forts to achieve it by the membersof Mr. Hayess department. Asearly as 1896, stirred by the recentinvention of the X-ray tube, JohnStone Stone undertook studies andexperiments of ways of utilizing theX-ray or similar tubes as a telephonerelay. Similar studies were begunin 1904 of methods of using the mer-cury-vapor arc—invented by PeterCooper Hewitt—as a telephone am-plifier; and in 1906 and 1907, G. A.Campbell and T. C. Hebb studiedthe negative-resistance characteristicsof the electric art with a similar ob-jective in view. Far-sighted Investigations This was by no means the first in-stance where the far-sightedness of Mr. Hayes stimulated investigationsthat were so much in advance of theirtime that immediate practical resultscould not be obtained. In 1892,only a few years after the discovery *of Hertzian waves and before

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