162 BELL SYSTEM TECHNICAL JOURNAL 



intervals, making connection between the zinc anodes and the cable sheaths 

 by buried wire. The cable-to-earth potentials were appreciably affected 

 throughout the entire 120 route miles across the Great Salt Desert by this 

 procedure. 



During the year these anodes have been in place, the cables have re- 

 mained at a satisfactory negative potential to earth (.20 to .50 volt) with 

 a small current being constantly drained to the zinc anodes. It is con- 

 sidered from the results to date that for similar areas the use of metallic 

 anodes offers an economical and satisfactory means for protecting buried 

 cables against corrosion. 



Transmission Networks for Frequency Modulation and Television? Har- 

 old S. Osborne. Looking forward to a great post war expansion in the 

 arts of frequency modulation and television this paper discusses plans of the 

 Bell System for providing transmission networks required for the inter- 

 connection of broadcast stations. A review of cable and open-wire car- 

 rier systems shows how developments for purely message telephone business 

 have at the same time put the Bell System in a position of being able at the 

 present time to meet such network transmission requirements for frequency 

 modulation as the broadcasters may select as desirable. Coaxial develop- 

 ments are reviewed briefly, including the application of these developments 

 to television transmission. Future developments, together with the coaxial 

 construction plans now under way, are expected to provide by about 1950 

 a fairly comprehensive nationwide network of facilities capable of providing 

 for such transmission requirements as may be desired by the television 

 industry. The important features involved in the operation of such net- 

 works are discussed, indicating a requirement for a highly trained nation- 

 wide organization and much equipment — a requirement which the Tele- 

 phone Companies can face with confidence because of their experience in 

 handling nationwide communications. 



Visible Patterns of Sound} Ralph K. Potter. New ways of trans- 

 lating sounds into pictures are described. These methods of sound por- 

 trayal are unique because what may be seen in the sound patterns is con- 

 sistent with what is heard in the original sound. The pictures display the 

 three basic dimensions of sound-pitch, loudness and time — in a form some- 

 what analogous to a musical score. Experimental training has shown that 

 with practice one may learn to read such patterns of speech so that the 

 development offers the ultimate possibility of aid to the severely deafened in 

 learning to speak correctly and to use the telephone by seeing rather than 

 hearing the voice of the distant speaker. The patterns will also be of 

 considerable interest in the fields of speech science and music. 



^ Elec. Engg., November 1945. 



^Science, November 9, 1945; Bell Tel. Sys. Monograph B-1368. 



