THE BELL SYSTEM 



TECHNICAL JOURNAL 



VOLUME XII, 1933 

 Table of Contents 



January, 1933 



Pulp Insulation for Telephone Cables — • 



H. G. Walker and L. S. Ford 1 

 A Recording Transmission Measuring System for Telephone 



Circuit Testing — F. II. Best 22 



Probability Theory and Telephone Transmission Engineering — 



Ray S. Hoyt 35 



An Oscillograph for Ten Thousand Cycles — A. M. Curtis 76 



Contemporary Advances in Physics, XXY — High-Frequency 



Phenomena in Gases, Second Part — Karl K. Darrow 91 



April, 1933 



Ultra-Short Wave Propagation — 



/. 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 — 



/. //. Sea ff and E. E. Schumacher 178 

 Some Results of a Study of Ultra-Short Wave Transmission 

 Phenomena — 



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

 New Results in the Calculation of Modulation Products— 



W. R. Bennett 228 

 3 



