Vol. 31. MARCH 1891. No. 190. 



Published the First Day of every Month* 



THE 

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PHILOSOPHICAL MAGAZINE. 



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JOURNAL OF SCIENCE. 



Being a Continuation of TillocKs ' ''Philosophical Magazine/ 

 Nicholson's 'Journal/ and Thomsons 'Annals of Philosophy.'' 



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SIR WILLIAM THOMSON, Knt. LL.D. P.R.S. &c. 

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FIFTH SERIE 



N° 190.— MARCH 1891. 



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Illustrative of Mr. M. Caeet Lea's Paper on Gold-coloured Allotro] 

 Silver, and Mr. E. B. Eosa's on the Specific Inductive Capacity of 



Electrolytes. 



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