Fol. 46. SEPTEMBER 1873. No. 305 



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THE 

 LONDON, EDINBURGH, am> DUBLIN 



PHILOSOPHICAL MAGAZINE, 



AND 



JOURNAL OF SCIENCE. 



Being a Continuation of Tilloch's 'Philosophical Magazine/ 

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



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

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FOURTH SERIES. 



N° 305.— SEPTEMBER 1873. 



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