STol.ll. JANUARY 1881. No. 65. 



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



THE 

 LONDON, EDINBURGH, and DUBLIN 



PHILOSOPHICAL MAGAZINE, 



AND 



JOURNAL OF SCIENCE. 



Being a Continuation of Tilloctis 'Philosophical Magazine? 

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



CONDUCTED BY 



SIR ROBERT KANE, LL.D. F.R.S. M.R.I.A. F.C.S. 

 SIR WILLIAM THOMSON, Knt. LL.D. F.R.S. Ac. 



. AND 



WILLIAM FRANCIS, Ph.D. F.L.S. F.R.A.S. F.C.S. 



FIFTH SERIES. 



N° 65.— JANUARY 1881. 



WITH A PLATE. 



Illustrative of MM. Lecher and Pernter's Paper on the Absorption 

 of dark Heat-rays by Gases and Vapours. 



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