Mutual impedance of crossing earth-return circuits

The mutual impedance between two straight-line earth-return circuits, making an angle different from zero with each other, is considered in the paper. Furthermore, it is shown that, when the angle between the lines is small, the mutual impedance may he determined from the expression concerning parallel wires. Tables are given for the functions P(r, ¿) and Q(r, ¿), which appear in equations for mutual impedances.