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BELL SYSTEM TECHNICAL JOURNAL 



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FREQUENCY- KILOCYCLES 



Fig. 2 — Attenuation variation with weather. 



The deposits on the wire may be actual ice, or in some cases wet 

 snow or frost adhering to the wire. Figure 3 shows an example of such 

 deposits. Theory shows that the increase in attenuation is caused by 

 energy losses in the ice itself and that leakage across the insulators is 

 usually a negligible factor. 



An extensive survey of the effects of ice has been carried on at 

 various points throughout the country during the past four years and a 



