TRANSATLANTIC RADIO TELEPHONY 353 



A summation of the voltages around the above defined rectangle 

 yields 



Subtracting (106) from (104) we get 



.z-/.- + l|=-^^. . ao7) 



If we write Q as the charge, C as the capacity to ground, and L as the 

 external inductance, each per unit length of the wire, equation (107) 

 becomes 



but the line current is decreased by the amount of the charging 

 current and the leakage current 



-i=f + ^^. (-) 



where ly is the leakage current per unit length of the wire. If the 

 admittance of the leak to ground be designated as Y, the leakage 

 current is 



Iy= YV" = F(r+ F). (110) 



Since we are interested only in the steady state, the operator d\dt 

 may be replaced by joj. Substituting the expression (110) for ly into 

 (109) and differentiating with respect to x yields 



dx^ dx dx C dx 



By means of (111) we may eliminate Q from (108) 



and if 



7 = V(s+jLa;)(F+jCc.), (114) 



where K is the characteristic impedance and 7 the propagation con- 



