Vol. 26. OCTOBER 1888. No. 161 



Published the First Day of every Month. — Price 2s. 6d. 



THE 

 LONDON, EDINBURGH, and DUBLIN 



PHILOSOPHICAL ^GAZINE, 



. AND • 



JOURNAL OF SCIENCE. 



Being a Continuation of TillocKs 'Philosophical Magazine, 

 Nicholson 8 '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. 



FIFTH SERIES. 



N° 161.— OCTOBER 1888. 



LONDON: 



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