Vol.10. JULY 1880. No. 59. 



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 TillocKs 'Philosophical Magazine, 

 Nicholson's i 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. 



r, 



*? 



FIFTH SERIES. 



N° 59.— JULY 1880. 



LONDON: ■ 



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