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BELL SYSTEM TECHNICAL JOURNAL 



by the first term of such a series, and the total field intensity may be 

 written 



N-l 00 



J = o s = o 



Pj and 4:j being referred to the axis of wire j, as shown in Fig. 5. That 

 is, the resultant field is expressible as a set of waves centered on the 

 axis of the cable and the axes of the N armor wires. 



Fig. 5 



In the neighborhood of the armor wires the arguments of the Bessel 

 functions are sufficiently small ^ to permit of the approximations 



where 



and 



Ko (ap) = K - log p, 



K = 0.11593 log—, 

 a 



Ks («p) = 



1 



( - apY 



' See Note I at end of paper. 



