74 PROCEEDINGS OF THE AMERICAN ACADEMY. 



I' distance of a point on a line from its far end 



(km.)- 



n frequency of single A. C. (cycles per second). 



oj angular velocity of A. C. (radians per second). 



j) t q cartesian coordinates of a point in a plane. 



r, r tfl r v r 2 , r a linear resistance of a single line, loop-line, 



and sections (ohms/km.). 

 B, B g , B gA ..., Bf, B M ... resistance of a line beyond a point on the 



same, the resistance when the far end is 



grounded, and when the far end is free, 



A. C. impedance (ohms). 

 B! = \/g' resistance (A. C. impedance) of leak of a T 



(ohms). 

 B" = \lg" resistance (A. C. impedance) of leak of a n 



(ohms). 

 p = 1// resistance (A. C. impedance) of line-branch of 



T (ohms). 

 p" = \jy" resistance (A. C. impedance) of architrave of 



n (ohms). 

 <r resistance (A. C. impedance) of impedance 



load (ohms). 

 0, lfl 6x, On, 3 .... hyperbolic angle subtended by a single line, 



loop-line, and sections (hyps). 

 y = l/z - surge-admittance (D. C. conductance) of a 



line (mhos). 

 y = l/p' admittance (D. C. conductance) of a line- 

 branch of a T (mhos). 

 y" = l/p'' admittance (D. C. conductance) of architrave 



of a n (mhos). 

 u, u A , Up potential, at the sending-end, and at a point 



on the line (volts). 

 Z n Z s impedance of a terminal receiver, of terminal 



sending apparatus (ohms). 

 z, z n , z x , Co, c 3 .... surge-impedance of a line, a loop-line, and 



sections (ohms). 

 z apparent surge-impedance of a line to which 



an impedance load is prefixed (ohms). 



