THE 

 LONDON, EDINBURGH, and DUBLIN 



PHILOSOPHICAL MAGAZINE 



AND 



JOURNAL OF SCIENCE. 



[FOURTH SERIES.] 



MA Y 1868. 



XXXIX. On " Inductive Circuits" or the Application of Ohm's 

 Law to Problems of Electrostatics. By F. C. Webb, M.I.C.E* 



PROBLEMS relating to the distribution of electricity on 

 conductors of different shapes, and on conductors and 

 Leyden jars differently grouped, have from time to time formed 

 the subject of mathematical investigation by many able mathe- 

 maticians. The results of the labours of George Green appear, 

 according to Sir William Thomson, the most important ; for Sir 

 William has remarked, in a paper read before the British Asso- 

 ciation, that " there is no branch of natural philosophy of which 

 the elementary laws are more simple than those which regulate 

 the distribution of electricity upon conducting bodies; yet its 

 impracticability has always been the reproach of the mathema- 

 tical theory of electricity The researches of our country- 

 man, Green, have entirely removed this forbidding aspect from 

 the theory of electricity, and led to the elementary propositions 

 which must constitute the legitimate foundation of every perfect 

 mathematical structure that is to be made from the materials 

 furnished in the experimental laws of Coulomb." 



In spite of this great advance, problems of electrostatics in 

 their generality must belong to a very high class of mathe- 

 matics. 



There is a large class of problems of this nature which may, 

 however, be solved by a very simple consideration of the subject 

 and the application of Ohm's formula for conduction. It is not 

 pretended that by this method all such problems can be solved 

 that are soluble by the complete mathematical theory; still, 

 out of the few examples of the application of Green's method 

 * Communicated by the Author. 



Phil. Mag. S. 4 Vol. 35. No. 238. May 1868. Z 



