II 111 



VOLUME xm JANUMy,, i^^^ „ 



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NUMBER 1 



THE BELL SYSTEM 



TECHNICAL JOURNAL 



DEVOTED TO THE SCIENTIHC AND ENGINEERING ASPECTS 

 OF ELECTRICAL COMMUNICATION 



Stabilized Feedback Amplifiers — H. S. Black ... 1 



Open-Wire Crosstalk — A. G. Chapman 19 



Vacuum Tube Electronics at Ultra-high Frequencies — 



F. B. Llewellyn 59 



Contemporary Advances in Physics, XXVII — The 



Nucleus, Second Part — Karl K. Darrow .... 102 



Abstracts of Technical Papers 159 



Contributors to this Issue 161 



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