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BELL SYSTEM TECHNICAL JOURNAL 



the above fibers plotted against relative humidity over the upper 

 part of the range of atmospheric humidities. It is not practicable 

 to plot the resistance over the entire range of humidity directly in 

 this way, on account of the wide range of insulation resistance values 

 which are obtained. In order to depict the fact that there is a con- 

 sistent relationship throughout the range, we have plotted in Fig. 3 



^ 8 



5 



Z 6 

 < 



20 40 60 80 



RELATIVE HUMIDITY — PER CENT 



Fig. 3 — Log insulation resistance of }/2 inch lengths of textile threads vs. relative 



humidity of the atmosphere. For description of samples see Fig. 2. 



For tabulated data see reference ia 



Log Insulation Resistance vs. Relative Humidity as far as values are 

 at present available. When considered together, these three charts 

 show that the insulation resistance of a textile depends on its moisture 

 content, which in turn is a function of relative humidity. In the 

 series of papers previously mentioned,^ the electrical behavior of 

 textiles in relation to relative humidity and moisture content is dis- 

 cussed more fully. 



Aside from the common property of dependence of electrical charac- 

 teristics of textiles upon their moisture contents, several other phe- 

 nomena of electrical behavior have been encountered which are 



