Vol. 36. OCTOBER 1868. No. 243- 



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 TillocKs 'Philosophical Magazine? 

 Nicholson 3 s 'Journal? and Thomson's c Annals of Philosophy. 9 



4 



■A 



CONDUCTED BY 



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. 



N° 243.— OCTOBER 1868. 



WITH A PLATE, 

 Illustrative of Prof. R. Btjnsen's Paper on Rhodium. 



LONDON: 



PRINTED BY TAYLOR AND FRANCIS, RED LION COURT, FLEET STREET, 



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