Vol. 49. MAY 1875. No. 326. 



Published the First Day of every Month. — Price 2s. Qd. 



THE 

 LONDON, EDINBURGH, and DUBLIN 



PHILOSOPHICAL MAGAZINE, 



AND 



JOUKNAL OF SCIENCE. 



Being a Continuation of Tilloch's 'Philosophical Magazine/ 

 Nicholson's ' Journal/ and Thomson's ' Annals of Philosophy.' 



CONDUCTED BY 



SIR ROBERT KANE, LL.D. F.R.S. M.R.I.A. F.C.S. 

 SIR WILLIAM THOMSON, Knt. LL.D. F.R.S. &c. 



AND 



WILLIAM FRANCIS, Ph.D. F.L.S. F.R.A.S. F.C.S. 



FOURTH SERIES. 



N° 326.— MAY 1875. 

 WITH TWO PLATES, 



Illustrative of Prof. Gr. C. Foster's Paper on Graphical Methods of sol- 

 ving certain simple Electrical Problems, and Messrs. G-. C. Foster and 

 O.J. Lodge's on the Flow of Electricity in a uniform plane conducting 

 Surface. 



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