

Vol. 26. JULY 1888. No. 158. 



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



THE 

 LONDON, EDINBURGH, and DUBLIN 



PHILOSOPHICAL MAGAZINE, 



AND 



JOURNAL OF SCIENCE. 



Being a Continuation of Tilloclis 'Philosophical Magazine^ 

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



£ " 



V\ CONDUCTED BY 



V 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° 158.- JULY 1888. 



LONDON: 



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