Vol. 25. FEBRUARY 1888. No. 153. 



Published the First Bay of every Month.— Price 2s. Qd. 



THE 

 LONDON, EDINBURGH, and DUBLIN 



PHILOSOPHICAL MAGAZINE, 



AND 



JOURNAL OF SCIENCE. 



Being a Continuation of Tilloclis ' Philosophical Magazine,'' 

 Nicholson's 'Journal? and Thomsons '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 



■Tes35WLLIAM FRANCIS, Ph.D. F.L.S. F.R.A.S. F.C.S. 





FIFTH SERIES. 



N° 153.— FEBRUARY 1888. 



LONDON: 



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