Vol. 21. 



FEBRUARY 1886. 



No. 129. 



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



THE 

 LONDON, EDINBURGH, and DUBLIN 



PHILOSOPHICAL MAGAZINE, 



AND 



JOURNAL OF SCIENCE. 



Being a Continuation of TillocKs 'Philosophical Magazine] 

 Nicholsons 'Journal? and Thomson's l 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.O.S. 



FIFTH SERIES. 



N° 129.— FEBRUARY 1886. 



X 1 



LONDON: 



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