Vol. ^7. MARCH 1889. No. 166. 



Published the First Day of every Month. — Price 2s. Qd. 



f M^v 



,^ ,t,K)«DON, EDINBURGH, asd DUBLIN 



PHILOSOPHICAL MAGAZINE, 

 JOUENAL OF SCIENCE. 



Being a Continuation of Tillooh^s 'Philosophieal Magazine,^ 

 Nicholson s ''Journal^ and Thomson's 'Annals of Philosophy.^ 



CONDUCTED BY 



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FIFTH SERIES. 



N" 166.— MARCH 1889. 



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