M.8. AUGUST 1879. No. 47. 



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, 

 Nicholsons 'Journal/ and Thomson's ( Annals of Philosophy.' 



CONDUCTED BY 



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

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AND 



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





FIFTH SERIES. 



N° 47.— AUGUST 1879. 



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