Vol. 36. NOVEMBER 1868. No. 244, 



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



THE 

 LONDON, EDINBURGH, and DUBLIN 



PHILOSOPHICAL MAGAZINE, 



AND 



JOURNAL OF SCIENCE. 



Being a Continuation of Tilloch's 'Philosophical Magazine, 9 

 Nicholson's 'Journal/ and Thomson's 'Annals of Philosophy, 9 



CONDUCTED RY 



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



AND 



WILLIAM FRANCIS, Ph.D. F.L.S. F.R.A.S. F.C.S. 



■*. FOURTH SERIES. 



****^^Tf s ^.— NOVEMBER 1868. 





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