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BELL SYSTEM TECHNICAL JOURNAL 



than through moisture condensed on their surfaces. Other evidences 

 that this is the case may be found in the relationships of conductivity 

 to humidity, moisture content and electrolyte content, as well as 

 the absence of any obvious relationship between the physical dimen- 

 sions of different classes of fibers and their electrical behavior. 



TABLE II 



Resistance of Different Lengths of Cotton Thread 



Humidity about 77 per cent Room temperature 



Resistance Megohms 

 Length Inches Total Per Inch 



0.5 21,700 43,400 



1 41,750 41,750 



3 153,000 51,000 



20 30 40 50 60 70 80 90 loo 



RELATIVE HUMIDITY— PER CENT 



Fig. 1 — Dependence of moisture content of textiles upon relative humidity of 

 atmosphere with which they are equilibrated 



While the form of the sample is not of predominating importance 

 with reference to the insulation resistance of either cotton or silk, 

 the marked contrast except at very high humidity between cotton 

 and silk in all forms of samples should be noted. Both these facts 

 and other available data justify the inference that the dielectric 

 properties of textiles are determined primarily by the composition or 



