ELECTROMAGNETIC FIELD ANALYSIS 509 



we interpret these equations in such a way that we can apply them to one- 

 dimensional transmission lines. In so doing we refrain from making ap- 

 proximations which we normally make when applying Kirchhoff laws to 

 networks of lumped elements. In the latter case it is usual to ignore the 

 inductance of the connecting leads or rather the inductance associated 

 with the loop formed by the leads; but in the case of two-wire transmission 

 lines the "connecting leads" constitute the entire network and the loop 

 inductance is no longer ignored. In the case of lumped networks the 

 capacitance between the connecting leads is normally neglected; but this 

 capacitance is scrupulously included in the analysis of two-wire lines since 

 in this case the "lead capacitance" is all the capacitance there is. And I 

 have already referred to a recent contribution of Kron's who presented a 

 three-dimensional network such that if we apply Kirchhoff 's laws to it, we 

 shall obtain Maxwell's field equations. The merger between the two points 

 of view is now complete. In its growth, each theory has developed concepts 

 peculiar to itself. The net result is that we are now in a position to under- 

 stand electromagnetic phenomena better than ever. 



