ol- 31. MAY 1866. No. 210. 



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THE 

 LONDON, EDINBURGH, and DUBLIN 



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JOURNAL OF SCIENCE. 



Being a Continuation of Tilloch's e Philosophical Magazine' 

 Nicholson's 'Journal? and Thomson's 'Annals of Philosophy' 



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FOURTH SERIES. 



N° 210.— MAY 1866. 



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