lfol. 15 



MAY 1883. No. 95 



Published the First Day of every Month. — Price 2s. 6d. 



THE 

 LONDON, EDINBURGH, and DUBLIN 



PHILOSOPHICAL MAGAZINE, 



AJSTD 



JOURNAL OF SCIENCE. 



Being a Continuation of TillocJis 'Philosophical Magazine, 

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



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~ -— -r|^^ 



FIFTH SERIES. ^%3 



N° 95.— MAY 1883. 



WITH TWO PLATES. 



Illustrative of Mr. L. Weight's Paper on the Optical Combinations of 

 Crystalline Films, and Mr. J. Rand Capeon's on the Auroral Beam 

 of November 17, 1882. 



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