THE 



M - 

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PHILOSOPHICAL MAGAZINE 



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JOURNAL OF SCIENCE. 



CONDUCTED BY 



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

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WILLIAM FRANCIS, Ph.D. F.L.S. F.R.A.S. F.C.S. 



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

 vilior quia ex alienis libamus ut apes." Just. Lips. Polit. lib. i. cap. 1. Not. 



VOL. XLVL— FOURTH SERIES. 

 JULY— DECEMBER 1873. 





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