ol. 36 



DECEMBER 1868. 



No. 245. 



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



THE 



LONDON, EDINBURGH, and DUBLIN 



PHILOSOPHICAL MAGAZINE, 



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Being a Continuation of Tilloch's * Philosophical Magazine/ 

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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° 245.— DECEMBER 1868. 



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Illustrative of Mr. J. J. Sylvester's Paper on Successive Involutes 



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