THE BELL SYSTEM TECHNICAL JOURNAL 



Published quarterly by the 



American Telephone and Telegraph Company 



195 Broadway^ New York, N. Y. 



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Bancroft Gherardi 

 L. F. Morehouse 

 D. Levinger 



EDITORIAL BOARD 



H. P. Charlesworth 

 E. H. Colpitts 

 O. E. Buckley 



F. B. Jewett 



O. B. BlackweU 



H. S. Osborne 



Philander Norton, Editor 



J. O. Perrine, Associate Editor 



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SUBSCRIPTIONS 



Subscriptions are accepted at $1.50 per year. Single copies are fifty cents each. 

 The foreign postage is 35 cents per year or 9 cents per copy. 



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Copyright, 1935 



PRINTED IN U. 8. A. 



