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BELL SYSTEM TECHNICAL JOURNAL 



may cause a change of about 10 per cent in resistance, these data are 

 considered significant in such testing methods as are used for electrical 

 textiles. 



In a previous publication ^ a series of simple equations was formu- 

 lated to show the quantitative relations between moisture content, 



1 2 3 4 6 6 7 



MOISTURE CONTENT IN PER CENT (BY WEIGHT) 



Fig. 3 — Moisture content-resistance relation for rag paper. 

 relative humidity, and the resistance (S2) of cotton: 



logfi = - A{%M. C.) +5, 

 logfi = - a(log%M. C.) +h, 

 logfi = - a(%R. H.) 4-^. 



(1) 

 (2) 

 (3) 



Equation 1 was considered as applying for moisture contents in 

 the vicinity of 3 per cent. Equation 2 between 3 per cent and 10 per 

 cent M. C, and Equation 3 from 10 per cent M. C. to saturation. 



