262 Methods for the Solution of Special Problems [CH. vm 



n = 1. This gives simply V x, a uniform field of force. 



n = 2. This gives V 2xy, so that the equipotentials are rectangular 

 hyperbolic cylinders, including as a special case two planes intersecting 

 at right angles (fig. 85). 



FIG. 85. 



FIG. 86. 



This transformation gives the field in the immediate neighbourhood of 

 two conducting planes meeting at right angles in any field of force. It also 

 gives the field between two coaxal rectangular hyperbolas. 



FIG. 87. 



