to 305 



THE I- 55* 



LONDON, EDINBURGH, and DUBLIN 



PHILOSOPHICAL MAGAZINE 



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JOURNAL OF SCIENCE. 



CONDUCTED BY 



SIR DAVID BREWSTER, K.H. LL.D. F.R.S.L. & E. &c. 

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

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" Nee aranearum sane textus ideo melior quia ex se fila gignunt, nee noster 

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VOL. XXXV.— FOURTH SERIES. 



JANUARY— JUNE, 1868. 







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