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THE BELL SYSTEM TECHNICAL JOURNAL 



ADVISORY BOARD 



F. E. K A P P E L, President, Western Electric Company 



M. J. KELLY, President, Bell Telephone Laboratories 



E. J. McNEELY, Executive Vice President, American 

 Telephone and Telegraph Company 



EDITORIAL COMMITTEE 



B. MCMILLAN, Chairman H. R. HUNTLEY 



A. J. BUSCH F. R. LACK 



A. C. DICKIESON J. R. PIERCE 



R. L. DIETZOLD H. V. SCHMIDT 



K. E. GOULD C. E. SCHOOLEY 



E. L GREEN G. N. THAYER 



EDITORIAL STAFF 



J. D. TEBO, Editor 



M. E. s T R I E B Y, Managing Editor 



R. L. SHEPHERD, Production Editor 



THE" BELL SYSTEM TECHNICAL JOURNAL is pubUshed six times 

 a year by the American Telephone and Telegraph Company, 195 Broadway, 

 New York 7, N. Y. Cleo F. Craig, President; S. Whitney Landon, Secretary; 

 John J. Scanlon, Treasurer. Subscriptions are accepted at $3.00 per year. 

 Single copies are 75 cents each. The foreign postage is 65 cents per year or 11 

 cents per copy. Printed in U. S. A. 



