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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f telegrams. It is re-corded that a British scientist, W. H.Barlow, after close observation of thisinterference to the telegraph, con-cluded in 1847 that the interferencecame from the earth. Soon thereafterit was recognized that these occasionsof severe interference to the tele-graph, called earth current storms,were associated with brilliant north-ern lights in the same manner as wasthe erratic behavior of compass nee-dles. In 1859 all the grounded tele-graph lines in the world were appar-ently affected by a very severe storm.During most of the seven-day periodfrom August 29 to September 4 ofthat year, it was impossible to trans-mit telegrams. On one line in Francewhich spanned a distance of 373 milesthe current was said to be ^equal tothat produced by a battery of 800volts. The effects of such storms havegradually become of much greater im-portance as first the telegraph, thenthe telephone, and lastly radio havebeen introduced and become more 19^0 Sun Spots and Telephone Service 185
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HAVUEN PLANETABIUM A RARE DISPLAY OF THE AURORA BOREALIS Showing both arches and streamers, this picture is reproduced from a pastel made more thanhalf a century ago by Etienne Trouvelot (1827-1895), artist and amateur astronomer widespread. Due to the presence ofthese and many other new services,and the dependence which our moderncivilization places on them, the greatmagnetic storm which occurred onSunday, March 24, 1940, probablyhad more diverse reactions on com-munication services than any thathave occurred before. It is believedthat readers of the Quarterly willbe interested in a discussion of thecauses of such storms and some in-formation about the March 24 storm,particularly as it affected Bell Systemservices. The underlying cause of the mag-netic and electrical disturbances on1 the earth probably resides in disturb- ances in solar activity, of which sunspots are perhaps only one manifesta-tion. This has become evident as aresult of a great amount of data takenover a long period

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