File:Bell telephone magazine (1922) (14776587243).jpg

Identifier: belltelephonemag19amerrich (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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Text Appearing Before Image:
y pole fixtures of various types.One tj^De of strengthening fixture isthe H fixture shown in Figure 12.Another is the push-pull brace, Fig-ure 13. The Bell System Cable Network liiACH aerial wire on a line picks upits own quota of ice, and when this ismultiplied by 30 or 40 wires, thereis considerable sail area exposed to the wind by the whole line. On theother hand, where the number of cir-cuits warrants, several hundred oreven thousand wires may be gatheredtogether under a common lead sheathforming a cable of less than threeinches in diameter. Such a cable,when it has accumulated a heavy icecoating, will present no more area to the wind than half a dozen similarlycoated open wires. Moreover, inorder to provide large strength mar-gins to permit aerial cables to supportsafely the weight of men employed intheir construction and maintenance,it is the practice to support aerialcables on stranded steel messengers,some of which have breaking strengths 19^0 Outwitting Open Wires Worst Foe 247
Text Appearing After Image:
Fig. 15. THE BELL SYSTEMS BASIC TOLL CABLE NETWORK This map has been abbreviated to show only the arterial cable routes already in service.Many important additions are planned, including a 1,600-mile extension from Omaha toSan Francisco, touching Denver and passing through Cheyenne, Salt Lake City, and Reno,and thus providing cable circuits from coast to coast, on which work is being begun this fall as high as 25,000 lbs. Consequently,ice accumulations on aerial cable,even if accompanied by wind, do nothave the adverse effect that they doon open wire, and relatively high linestrengths can be obtained for aerialcable lines rather easily and at mod-erate cost. For this reason aerialcable becomes a practically storm-proof plant. Such a line is shownin Figure 14, which is a photographof a long distance telephone cableextending from Greenfield, Massa-chusetts, to White River Junction, Vermont. Incidentally, this cable re-mained continuously in service duringthe hurricane of September, 1938

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