Vol.4. OCTOBER 1877. No. 26. 



Published the First Day of every Month, — Price 28, Qd. 



THE 

 LONDON, EDINBURGH, AxXd DUBLIN 



PHILOSOPHICAL MAGAZINE, 



AND 



JOURNAL OF SCIENCE. 



Bein^ a Continuation of TillocKs ^Philosophical Magazine,^ 

 Nicholson^ 8 'JowrrwX^ and ThomsorCs ^Annals of Philosophy.^ 



CONDUCTED BY 



SIR ROBERT KANE, LL.D. F.R.S. M.R.LA. 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. 



FIFTH SERIES. 



N° 25.— OCTOBER 1877, 



LONDON; 



FEINTED BY TAYLOR AND FBANCI8, BED LION COURT, FLEET STREET, 

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