Vol. 36. 



AUGUST 1868. 



No. 241 



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 TillocKs ( Philosophical Magazine,' 

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



CONDUCTED BY 



SIR ROBERT KANE, iM.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° 241.— AUGUST 1868. 







WITH A PLATE, 

 Illustrative of Mr. H. Wilde's Experimental Researches in Magnetism 



and Electricity. 



LONDON: 



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



Printers and Publishers to the University of London. 

 Sold by Longmans, Green, Reader and Dyer ; Kent and Co. ; Simpkin, Marshall and 

 Co. ; Whittaker and Co. ; and H. Bailliere, London :— and by A. and C. Black, and 

 Thomas Clark, Edinburgh; Smith and Son, Glasgow :— Hodges and Smith, 

 Dublin : — and Putnam, New York. # 



'S™y°f Smithsonian Institution] 

 — ■^■^sr^ — 

 . WlLLi AM WESLEY 

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