>L 36. AUGUST v^gs. < No. 219 



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 LONDON, EDINBURGH, and DUBLIN 



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JOURNAL OF SCIENCE. 



Being a Continuation of Tilloclis ' Philosophical Magazine/ 

 Nicholsons l Journal f and Thomsons l Annals of Philosophy.'' 



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FIFTH SERIES. 



N° 219.— AUGUST 1893. 



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