1. 40. NOVEMBER 1895. No. 246. 



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 Tilloch's 'Philosophical Magazine/ 

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



CONDUCTED BY 



LORD KELVIN, LL.D. P.R.S. <fcc. 



GEORGE FRANCIS FITZGERALD, M.A. Sc.D. F.R.S. 



AND 



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



FIFTH SERIES. 



j N° 246.— NOVEMBER 1895. 



WITH THEEE PLATES. 



Illustrative of Mr. E. H. Griefiths's Paper on the Thermal Unit, and 



Mr. H. Wilde's on Helium. 



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