THE BELL SYSTEM TECHNICAL JOURiNAL 



A D V I S O R \ IJ O A H I) 



S. B R A c K E N. President. H rs/crn /J/ectnc Company 



F. n. k A l> i» K L. lice Prcsidcif. A/neriran '/'clcpl/one 

 and 'VeU'<>:rnf)h ('oniparn- 



M. J. K ]•: L L N . Prexideitt. I><dl Telephone Lahornlones 



E D I r () H I A L C () M \l 1 T I i: E 



E. I. GREEN, Chairman 



^- J- '^ • ^ <: '« F. R. LACK 



VV. II. I) oil KllTY J. w. MCRAE 



G. D. E j:) w a II d s w. it. n it N N 



J. B. FI S K H. I. ROM NE S 



R. K. IIONAMAN H. V. S Oil M I D T 



EDITORIAL STAFF 



PHILIP C. JONES, Editor 



M. E. S T K I K 15 \. Mfinairirto; Editor 



R. L. 8 11 E 1' II K u 1). Paul „rt ion Editor 



THE BELL SYSTEM TECHNICAL JOURNAL is published 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; 

 Alexander L. Stott, 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. 



