VOLUME Xn APRIL, 1933 NUMBER 2 



THE BELL SYSTEM 



TECHNICAL JOURNAL 



DEVOTED TO THE SCIENTIFIC AND ENGINEERING ASPECTS 

 OF ELECTRICAL COMMUNICATION 



Ultra-Short Wave F*ropagatioii — 



J. C. Schelleng, C. R. Burrows and E. B. Ferrell . 125 



Mutual Impedance of Grounded Wires for Horizontally 

 Stratified Two-Layer Earth — 



John Riordan and Erling D. Sunde 162 



Some Theoretical and Practical Aspects of Gases in 



Metals— 7. H. Scaff and E. E. Schumacher . .178 



Some Results of a Study of Ultra-Short Wave Trans- 

 mission Phenomena — 

 C. R, Englund, A. B. Crawford and W. W, Mumford 197 



New Results in the Calculation of Modulation Prod- 

 ucts— W^. R. Bennett 228 



Abstracts of Technical Papers 244 



Contributors to this Issue 248 



AMERICAN TELEPHONE AND TELEGRAPH COMPANY 



NEW YORK 



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