™. 46. JULY 1873. No. 303. 



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THE 

 LONDON, EDINBURGH, ato DUBLIN 



PHILOSOPHICAL MAGAZINE, 



AND 



JOURNAL OF SCIENCE. 



Being a Continuation of Tilloch's 'Philosophical Magazine,' 

 Nicholson's 'Journal/ and Thomson's '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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WILLIAM FRANCIS, Ph.D. F.L.S. F.R.A.S. F.C.S. 



FOURTH SERIES. 



N° 303.— JULY 1873. 



WITH A PLATE, 



Illustrative of Mr. J. A. Phillips's Paper on the Composition and Origin 



of the Waters of a Salt Spring in Huel Seton Mine. 



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