Vol. 39. MARCH 1895. No. 238. 



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



THE 

 LONDON, EDINBURGH, and DUBLIN 



PHILOSOPHICAL MAGAZINE, 



AND 



JOURNAL OF SCIENCE. 



Being a Continuation of Tilloctis 'Philosophical Magazine / 

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



CONDUCTED BY 



LORD KELVIN, LL.D. P.R.S. Ac. 



GEORGE FRANCIS FITZGERALD, M.A. Sc.D. F.R.S. 



AND 



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



FIFTH SERIES. 



N° 238.— MARCH 1895. 



LONDON: 



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