Vol. 12. AUGUST 1881. No. 73. 



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THE 

 LONDON, EDINBURGH, and DUBLIN 



PHILOSOPHICAL MAGAZINE, 



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JOURNAL OF SCIENCE. 



Being a Continuation of TillocKs 'Philosophical Magazine? 

 Nicholson's c Journal ,' and Thomsons 'Annals of Philosophy,'' 



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FIFTH SERIES. , 



N° 73.— AUGUST 1881. > 



WITH A PLATE. 



Illustrative of Mr. C. J. Woodward's Paper on a Wave-apparatus for 

 Lecture-Purposes to illustrate Fresnel's Conception of Polarized Light. 



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