•1. 31. MARCH 1866. No. 208 



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 Tilloch's 'Philosophical Magazine? 

 Nicholson's 'Journal,' and Thomson's 'Annals of Philosophy' 



CONDUCTED BY 



SIR DAVID BREWSTER, K.H. LL.D. F.R.S. L.&E.&c. 

 SIR ROBERT KANE, M.D. F.R.S. M.R.I.A. 

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FOURTH SERIES. 



N° 208.— MAECH 1866. 



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