VOLUME XV JANUARY, 1936 number l 



THE BELL SYSTEM 



TECHNICAL JOURNAL 



DEVOTED TO THE SCIENTIHC AND ENGINEERING ASPECTS 

 OF ELECTRICAL COMMUNICATION 



Long-Wave Radio Transmission Phenomena Associated with 

 a Cessation of the Sun's Rays— 



Austin Bailey and A. E. Harper 1 



The Corrosion of Metals— I. Mechanism of Corrosion Proc- 

 esses — R. M. Burns 20 



Magnetic Measurements at Low Flux Densities Using the 



Alternating Current Bridge— Wcfor E. Legg 39 



The Present Status of Ferromagnetic Theory—/?. M. Bozorth 63 



Some Equivalence Theorems of Electromagnetics and Their 



Application to Radiation Problems— S. A. Schelkunoff . . 92 



Magnetic Alloys of Iron, Nickel, and Cobalt— G. W. Elmen 113 



Improvements in Communication Transformers — 



A. G. Ganz and A. G. Laird 136 



Technical Digests — 



1. Measurement of Telephone Noise and Power Wave Shape — 



/. M. Bar stow t P. W. Blye and H. E. Kent 151 



2. On the Correlation of Radio Transmission with Solar Phenomena — 



A. M. Skellett 157 



3. Eclipse Effects in the Ionosphere— /. P. Sc/ia/er and W.M.Goodall 162 



4. Earth Resistivity and Geological Structure — R. H. Card 167 



Abstracts of Technical Papers 172 



Contributors to this Issue 177 



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