'"Vol. 33. MARCH 1892. No. 202. 



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PHILOSOPHICAL MAGAZINE, 



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Being a Continuation of Tilloclis 'Philosophical Magazine' 

 Nicholson's l Journal f and Thomson s l Annals of Philosophy,' 



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

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FIFTH SERIES. 



N° 202.— MARCH 1892, 



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